Flanges general-for-dummies

FLANGES GENERAL
FOR DUMMIES
“It might be helped for the Engineers who are not eligible in certain fucking place”

2“If you can't explain it simply, you don't understand it well enough.” Albert Einstein
FLANGES GENERAL
A flange is a method of connecting pipes, valves, pumps and other equipment to form a piping
system. It also provides easy access for cleaning, inspection or modification. Flanges are usually
welded or screwed. Flanged joints are made by bolting together two flanges with a gasket between
them to provide a seal.
Pipe flanges are manufactured in all the different materials. Some flanges are made of cast and ductile
iron, but the most used material is forged carbon steel and have machined surfaces.
TYPES OF FLANGES
The most used flange types in Petro and chemical industry are:
 Welding Neck Flange
 Slip On Flange
 Socket Weld Flange
 Lap Joint Flange
 Threaded Flange
 Blind Flange
All types except the Lap Joint flange are provided with a raised flange face.
SPECIAL FLANGES
Except the flanges, which are mentioned above, there are still a number of special flanges such as:
 Orifice Flanges
 Spectacle Blinds (part of flange connection)
 Spades and Ring Spacers (part of flange connection)
 Long Welding Neck Flanges
 Weldoflange / Nipoflange
 Expander Flange
 Reducing Flange

MATERIALS FOR FLANGES
The most common materials used in flanges produced is carbon steel, stainless steel, cast iron,
aluminium, brass, bronze, plastic etc..
In addition, flanges, like fittings and pipes, for specific purposes sometimes internally equipped with
layers of materials of a completely different quality as the flanges themselves, which are
"lined flanges".
The material of a flange, is basically set during the choice of the pipe, in most cases, a flange is of the
same material as the pipe.
All flanges, discussed on this website fall under the ASME en ASTM standards, unless otherwise
indicated. ASME B16.5 describes dimensions, dimensional tolerances etc. and ASTM the different
material qualities.
DIMENSIOS OF FLANGES
Each flange according to ASME B16.5 has a number of standard dimensions.
If a draftsman in Japan or the work preparer in Canada or a pipefitter in Australia is speaking about a
Welding Neck flange 6"-150#-S40 according to ASME B16.5, then it goes over the flange which in the
image here below is shown.
If the flange is ordered, the supplier want to know the material quality. For example ASTM A105 is a
forged carbon steel flange, while A182 is a forged stainless steel flange.
So, in a correct order to a supplier two standards must be specified:
Welding Neck flange 6"-150#-S40-ASME B16.5 / ASTM A105.
BOLTED FLANGE CONNECTIONS
A bolted flange connection is a complex combination of many factors (Flange, Bolts, Process,
Temperature, Pressure, Medium).

All these various elements are interrelated and depend upon one another to achieve a successful
result.
The reliability of the flanged joint depends critically upon competent control of the joint making
process.
Quoting from John H. Bickford's book, "An Introduction to the Design and Behavior of Bolted
Joints":
That all important clamping force which holds the joint together - and without which there would be
no joint - is not created by a good joint designer, nor by high quality parts. It is created by the
mechanic on the job site, using the tools, procedures, and working conditions we have provided him
with... And further: The final, essential creator of the force is the mechanic, and the time of creation is
during assembly. So it's very important for us to understand this process.
The industry has recognized the critical nature of installation and assembly for several years.
In Europe, the emphasis has been on ensuring that joint making is undertaken by trained and
validated technicians and this has led to the publication of a European Technical standard: TS EN 1591
Part 4 entitled "Flanges and their joints. Design rules for gasketed circular flange connections.
Qualification of personnel competency in the assembly of bolted joints fitted to equipment subject to
the Pressure Equipment Directive (PED)".
The standard provides a methodology for the training and assessment of technicians involved in the
making and breaking of flange joints and can be viewed as being analogous to the training required
for welders involved with pressure vessel work. Its publication demonstrates the importance placed
upon the competent control of joint making process in ensuring leak-free performance from the
flange.
The gasket is but one of many reasons a bolted flange joint connection can leak.
Even when all the complex inter-related components of a bolted joint flange connection work in
perfect harmony, the single most important factor leading to success or failure of that bolted flange
connection will be attention given to proper installation and assembly procedures by the person
installing the gasket. If done properly, the assembly will remain leak-free for the target life
expectancy.
FLANGED CONNECTIONS VERSUS WELDED CONNECTIONS
There are no standards that define whether or not flange connections may be used.
In a newly built factory is customary to minimize flange connections, because only one weld is needed
to connect two pieces of pipe.
This saves the costs of two flanges, the gasket, the stud bolts, the second weld, the cost of NDT for
the second weld, etc..
Some other disadvantages of flange connections:
 Each flange connection can leak (some people claim that a flange connection is never 100 percent
leak proof).

 Flanged pipe systems need much more space (just think of a pipe rack).
 Insulation of flanged pipe systems is more expensive (special flange caps).
Of course, flange connections have great benefits; some examples:
 A new line can contain multiple pipe spools and can be manufactured in a workshop.
 This pipe spools can be assembled in the plant without the need to be welded.
 NDO (X-ray, Hydro test etc.) in the plant is not necessary, because this has been done in the
workshop.
 Blasting and painting in the plant is not necessary, because even this has been done in a workshop
(only paint damages during installation should be repaired).
As with many things, everything has its pros and cons.
PRESSURE CLASS
The Pressure Class or Rating for flanges will be given in pounds. Different names are used to indicate
a Pressure Class. For example: 150 Lb or 150 Lbs or 150# or Class 150, all are means the same.
Forged steel flanges are made in seven primary ratings:
150Lbs - 300Lbs - 400Lbs - 600Lbs - 900Lbs - 1500Lbs - 2500Lbs
The concept of flange ratings likes clearly. A Class 300 flange can handle more pressure than a Class
150 flange, because a Class 300 flange are constructed with more metal and can withstand more
pressure. However, there are a number of factors that can impact the pressure capability of a flange.
EXAMPLE
Flanges can withstand different pressures at different temperatures. As temperature increases, the
pressure rating of the flange decreases. For example, a Class 150 flange is rated to approximately 270
PSIG at ambient conditions, 180 PSIG at approximately 400°F, 150 PSIG at approximately 600°F, and
75 PSIG at approximately 800°F. In other words, when the pressure goes down, the temperature goes
up and vice versa.
Additional factors are that flanges can be constructed from different materials, such as stainless steel,
cast and ductile iron, carbon steel etc.. Each material have different pressure ratings.
PRESSURE-TEMPERATURE RATINGS
Pressure-temperature ratings are maximum allowable working gage pressures in bar units at the
temperatures in degrees celsius. For intermediate temperatures, linear interpolation is permitted.
Interpolation between class designations is not permitted.
Pressure-temperature ratings apply to flanged joints that conform to the limitations on bolting and on
gaskets, which are made up in accordance with good practice for alignment and assembly. Use of
these ratings for flanged joints not conforming to these limitations is the responsibility of the user.
The temperature shown for a corresponding pressure rating is the temperature of the pressure-
containing shell of the component. In general, this temperature is the same as that of the contained

fluid. Use of a pressure rating corresponding to a temperature other than that of the contained fluid is
the responsibility of the user, subject to the requirements of applicable codes and regulations. For any
temperature below -29°C, the rating shall be no greater than the rating shown for -29°C.
As an example, below you will find two tables with material groups acc. to ASTM, and two other tables
with flange pressure-temperature ratings for those ASTM materials acc. to ASME B16.5.
ASTM Group 2-1.1 Materials ASTM Group 2-2.3 Materials
Nominal
Designation
Forgings Castings Plates
Nominal
Designation
Forgings Castings Plates
C-Si A105(1)
A216
Gr.WCB(1)
A515
Gr.70(1)
16Cr-12Ni-
2Mo
A182
Gr.F316L
-
A240
Gr.316L
C-Mn-Si
A350
Gr.LF2(1)
-
A516
Gr.70(1),(2)
18Cr-13Ni-
3Mo
A182
Gr.F317L
- -
C-Mn-Si-V
A350
Gr.LF6 Cl 1(3)
-
A537
Cl.1(4)
18Cr-8Ni
A182
Gr.F304L(1)
-
A240
Gr.304L(1)
3½Ni
A350
Gr.LF3
- -
NOTES:
 (1) Upon prolonged exposure to temperatures above
425°C, the carbide phase of steel may be converted
to graphite. Permissible but not recommended for
prolonged use above 425°C.
 (2) Do not use over 455°C.
NOTE:
Pressure-Temperature Ratings for ASTM Group 2-1.1 Materials
Working pressures by classes, BAR
Temp.°C 150 300 400 600 900 1500 2500
-29 to 38 19.6 51.1 68.1 102.1 153.2 255.3 425.5
50 19.2 50.1 66.8 100.2 150.4 250.6 417.7
100 17.7 46.6 62.1 93.2 139.8 233 388.3
150 15.8 45.1 60.1 90.2 135.2 225.4 375.6
200 13.8 43.8 58.4 87.6 131.4 219 365
250 12.1 41.9 55.9 83.9 125.8 209.7 349.5
300 10.2 39.8 53.1 79.6 119.5 199.1 331.8
325 9.3 38.7 51.6 77.4 116.1 193.6 322.6
350 8.4 37.6 50.1 75.1 112.7 187.8 313
375 7.4 36.4 48.5 72.7 109.1 181.8 303.1
400 6.5 34.7 46.3 69.4 104.2 173.6 289.3

1. Weld Neck flange 2. Butt
Weld
3. Pipe or Fitting
425 5.5 28.8 38.4 57.5 86.3 143.8 239.7
450 4.6 23 30.7 46 69 115 191.7
475 3.7 17.4 23.2 34.9 52.3 87.2 145.3
500 2.8 11.8 15.7 23.5 35.3 58.8 97.9
538 1.4 5.9 7.9 11.8 17.7 29.5 49.2
Pressure-Temperature Ratings for ASTM Group 2-2.3 Materials
Working pressures by classes, BAR
Temp.°C 150 300 400 600 900 1500 2500
-29 to 38 15.9 41.4 55.2 82.7 124.1 206.8 344.7
50 15.3 40 53.4 80 120.1 200.1 333.5
100 13.3 34.8 46.4 69.6 104.4 173.9 289.9
150 12 31.4 41.9 62.8 94.2 157 261.6
200 11.2 29.2 38.9 58.3 87.5 145.8 243
250 10.5 27.5 36.6 54.9 82.4 137.3 228.9
300 10 26.1 34.8 52.1 78.2 130.3 217.2
325 9.3 25.5 34 51 76.4 127.4 212.3
350 8.4 25.1 33.4 50.1 75.2 125.4 208.9
375 7.4 24.8 33 49.5 74.3 123.8 206.3
400 6.5 24.3 32.4 48.6 72.9 121.5 202.5
425 5.5 23.9 31.8 47.7 71.6 119.3 198.8
450 4.6 23.4 31.2 46.8 70.2 117.1 195.1
FLANGE TYPES
As already before described, the most used flange types acc.
to ASME B16.5 are: Welding Neck, Slip On, Socket Weld,
Lap Joint, Threaded and Blind flange.
Here below you will find a short description and definition of
each type, completed with an detailed image.
WELDING NECK FLANGE
Welding Neck Flanges are easy to recognize at the long
tapered hub, that goes gradually over to the wall thickness
from a pipe or fitting.
The long tapered hub provides an important reinforcement
for use in several applications involving high pressure, sub-
zero and / or elevated temperatures. The smooth transition
from flange thickness to pipe or fitting wall thickness effected

by the taper is extremely beneficial, under conditions of repeated bending, caused by line expansion
or other variable forces.
These flanges are bored to match the inside diameter of the mating pipe or fitting so there will be no
restriction of product flow. This prevents turbulence at the joint and reduces erosion. They also
provide excellent stress distribution through the tapered hub and are easily radiographed for flaw
detection. This flange type will be welded to a pipe or fitting with a single full penetration, V weld
(Buttweld).
SLIP On FLANGE
The calculated strength from a
Slip On flange under internal
pressure is of the order of two-
thirds that of welding neck flanges,
and their life under fatigue is about
one-third that of the latter.
The connection with the pipe is
done with 2 fillet welds, as well at
the outside as also at the inside of the flange. The X measure on the image, are approximately: Wall
thickness of pipe + 3 mm.
This space is necessary, to do not damage the flange face, during the welding process.
A disadvantage of the flange is, that principle always firstly a pipe must be welded and then just a
fitting. A combination of flange and elbow or flange and tee is not possible, because named fittings
have not a straight end, that complete slid in the Slip On flange.
Socket Weld FLANGE
Socket Weld flanges were initially
developed for use on small-size
high pressure piping. Their static
strength is equal to Slip On
flanges, but their fatigue strength
50% greater than double-welded
Slip On flanges.
The connection with the pipe is done with 1 fillet weld, at the outside of the flange. But before
welding, a space must be created between flange or fitting and pipe.
ASME B31.1 1998 127.3 Preparation for Welding (E) Socket Weld Assembly says:
In assembly of the joint before welding, the pipe or tube shall be inserted into the socket to the
maximum depth and then withdrawn approximately 1/16" (1.6 mm) away from contact between the
end of the pipe and the shoulder of the socket.
1. Slip On flange 2. Filled
weld outside
3. Filled weld inside 4. Pipe
1. Socket weld flange 2.
Filled weld 3. Pipe
X = Expansion gap

The purpose for the bottoming clearance in a socket weld is usually to reduce the residual stress at
the root of the weld that could occur during solidification of the weld metal. The image shows you the
X measure for the expansion gap.
The disadvantage of this flange is right the gap, that must be made. By corrosive products, and
mainly in stainless steel pipe systems, the crack between pipe and flange can give corrosion problems.
In some processes this flange is also not allowed. I am not an expert in this matter, but on the
internet, you will find a lot of information about forms of corrosion.
Also for this flange counts, that principle always firstly a pipe must be welded and then just a fitting.
Lap Joint FLANGE
Lap Joint Flanges have all the
same common dimensions as any
other flange named on this page
however it does not have a raised
face, they used in conjunction with
a "Lap Joint Stub End".
These flanges are nearly identical
to a Slip On flange with the
exception of a radius at the
intersection of the flange face and the bore to accommodate the flanged portion of the stub end.
Their pressure-holding ability is little, if any, better than that of Slip On flanges and the fatigue life for
the assembly is only one tenth that of welding neck flanges.
They may be used at all pressures and are available in a full size range. These flanges slip over the
pipe, and are not welded or otherwise fastened to it. Bolting pressure is transmitted to the gasket by
the pressure of the flange against the back of the pipe lap (Stub End).
Lap Joint flanges have certain special advantages:
 Freedom to swivel around the pipe facilitates the lining up of opposing flange bolt holes.
 Lack of contact with the fluid in the pipe often permits the use of inexpensive carbon steel
flanges with corrosion resistant pipe.
 In systems which erode or corrode quickly, the flanges may be salvaged for re-use.
Stub End
A Stub End always will be used with a Lap Joint flange, as
a backing flange.
This flange connections are applied, in low-pressure and
non critical applications, and is a cheap method of
flanging.
In a stainless steel pipe system, for example, a carbon
steel flange can be applied, because they are not come in
1. Lap Joint flange
2. Stubend
3. Butt weld 4. Pipe
or Fitting

contact with the product in the pipe.
Stub Ends are available in almost all pipe diameters. Dimensions and dimensional tolerances are
defined in the ASME B.16.9 standard. Light-weight corrosion resistant Stub Ends (fittings) are defined
in MSS SP43.
THREADED FLANGE
Threaded Flanges are used for
special circumstances with their
main advantage being that they
can be attached to the pipe
without welding. Sometimes a seal
weld is also used in conjunction
with the threaded connection.
Although still available in most
sizes and pressure ratings,
screwed fittings today are used almost exclusively in smaller pipe sizes.
A threaded flange or fitting is not suitable for a pipe system with thin wall thickness, because cutting
thread on a pipe is not possible. Thus, thicker wall thickness must be chosen...what is thicker ?
ASME B31.3 Piping Guide says:
Where steel pipe is threaded and used for steam service above 250 psi or for water service above 100
psi with water temperatures above 220° F, the pipe shall be seamless and have a thickness at least
equal to schedule 80 of ASME B36.10.
BLIND FLANGE
Blind Flanges are manufactured without a bore and used
to blank off the ends of piping, valves and pressure
vessel openings.
From the standpoint of internal pressure and bolt
loading, blind flanges, particularly in the larger sizes, are
the most highly stressed flange types.
However, most of these stresses are bending types near
the center, and since there is no standard inside
diameter, these flanges are suitable for higher pressure
temperature applications.
1. Threaded flange 2. Thread 3. Pipe or Fitting
1. Blind flange 2. Stud
Bolt 3. Gasket 4. Other

FLANGE FACES
Different types of flange faces are used as the contact surfaces to seat the sealing gasket material.
ASME B16.5 and B16.47 define various types of flange facings, including the raised face, the large
male and female facings which have identical dimensions to provide a relatively large contact area.
Other flange facings covered by these standards include the large and small tongue-and-groove
facings, and the ring joint facing specifically for ring joint type metal gaskets.
RAISED FACE (RF)
The raised face flange face is the most common type used in process plant applications, and is
easily to identify. It is referred to as a raised face because the gasket surfaces are raised above the
bolting circle face. This face type allows the use of a wide combination of gasket designs, including flat
ring sheet types and metallic composites such as spiral wound and double jacketed types. The
purpose of a RF flange is to concentrate more pressure on a smaller gasket area and thereby increase
the pressure containment capability of the joint. Diameter and height are in ASME B16.5 defined, by
pressure class and diameter. Pressure rating of the flange determines the height of the raised face.
The typical flange face finish for ASME B16.5 RF flanges is 125 to 250 µin Ra (3 to 6 µm Ra).
Raised Face height
For the height measures H and B of all
described dimensions of flanges on this
website, with exception of the Lap Joint
flange, it is important to understand and
remember the following:
In Pressure Classes 150 and 300 Lbs, the height of raised face is approximately 1.6 mm (1/16 inch).
In these two Pressure Classes, almost all suppliers of flanges, show in their catalog or brochure, the
H and B dimensions including the raised face height. See figure 1 on the image below.

In Pressure Classes 400, 600, 900, 1500 & 2500 Lbs, the height of raised face is approximately
6.4 mm (1/4 inch). In these Pressure Classes, most suppliers show the H and B dimensions excluding
the raised face height. See figure 2 on the image above.
FLAT FACE (FF)
The flat face flange has a gasket
surface in the same plane as the
bolting circle face. Applications
using flat face flanges are
frequently those in which the
mating flange or flanged fitting is made from a casting.
Flat face flanges are never to be bolted to a raised face flange. ASME B31.1 says that when connecting
flat face cast iron flanges to carbon steel flanges, the raised face on the carbon steel flange must be
removed, and that a full face gasket is required. This is to keep the thin, bittle cast iron flange from
being sprung into the gap caused by the raised face of the carbon steel flange.
RING-TYPE JOINT (RTJ)
The ring type joint flanges are
typically used in high pressure
(Class 600 and higher rating)
and/or high temperature services
above 800°F (427°C). They have
grooves cut into their faces which
steel ring gaskets. The flanges seal when tightened bolts compress the gasket between the flanges
into the grooves, deforming (or Coining) the gasket to make intimate contact inside the grooves,
creating a metal to metal seal.
An RTJ flange may have a raised face with a ring groove machined into it. This raised face does not
serve as any part of the sealing means. For RTJ flanges that seal with ring gaskets, the raised faces of
the connected and tightened flanges may contact each other. In this case the compressed gasket will
not bear additional load beyond the bolt tension, vibration and movement cannot further crush the
gasket and lessen the connecting tension.
Ring Type Joint gaskets
Ring Type Joint gaskets are metallic
sealing rings, suitable for high-pressure
and high-temperature applications.
They are always applied to special,
accompanying flanges which ensure

good, reliable sealing with the correct choice of profiles and material.
Ring Type Joint gaskets are designed to seal by "initial line contact" or wedging action between the
mating flange and the gasket. By applying pressure on the seal interface through bolt force, the
"softer" metal of the gasket flows into the microfine structure of the harder flange material, and
creating a very tight and efficient seal.
Most applied type is style R ring that is manufactured in accordance with ASME B16.20 used with
ASME B16.5 flanges, class 150 to 2500.
Style R ring type joints are manufactured in both oval and octagonal configurations. The octagonal
cross section has a higher sealing efficiency than the oval and would be the preferred gasket.
However, only the oval cross section can be used in the old type round bottom groove. The newer flat
bottom groove design will accept either the oval or the octagonal cross section. The sealing surfaces
on the ring joint grooves must be smoothly finished to 63 Microinches and be free of objectionable
ridges, tool or chatter marks. They seal by an initial line contact or a wedging action as the
compressive forces are applied. The hardness of the ring should always be less than the hardness of
the flanges.
Style R ring type joints are designed to seal pressure up to 6,250 psi in accordance with ASME B16.5
pressure ratings and up to 5,000 psi.
TONGUE-AND-GROOVE (T&G)
The tongue and groove faces
of this flanges must be matched.
One flange face has a raised ring
(Tongue) machined onto the flange
face while the mating flange has a
matching depression (Groove) machined into it's face.
Tongue-and-groove facings are standardized in both large and small types. They differ from male-and-
female in that the inside diameters of the tongue-and-groove do not extend into the flange base, thus
retaining the gasket on its inner and outer diameter. These are commonly found on pump covers and
valve bonnets.
Tongue-and-groove joints also have an advantage in that they are self-aligning and act as a reservoir
for the adhesive. The scarf joint keeps the axis of loading in line with the joint and does not require a
major machining operation.
General flange faces such as the RTJ, T&G and the F&M shall never be bolted together. The reason for
this is that the contact surfaces do not match and there is no gasket that has one type on one side
and another type on the other side.

MALE-AND-FEMALE (M&F)
With this type the flanges also must be matched. One flange face has an area that extends beyond the
normal flange face (Male). The other flange or mating flange has a matching depression (Female)
machined into it's face.
The female face is 3/16-inch deep, the male face is 1/4-inch high, and both are smooth finished. The
outer diameter of the female face acts to locate and retain the gasket. Custom male and female
facings are commonly found on the heat exchanger shell to channel and cover flanges.
ADVANTAGES AND DISADVANTAGES OF T&G AND M&F FLANGE FACES
Advantages:
Better sealing properties, more precise location and exact compression af sealing material, utilization
of other, more suitable sealing and spezialized sealing material (O-rings).
Disadvantages:
Commercial availabillity and cost. Normal raised faced is far more common and ready available both
regarding valves, flanges and sealing material. Another complexity is that some rigid rules must be
applied to the piping design. Do you order valves to be female end both sides, or on one side maybe,
in which case do you point all male ends in the flow direction, or what. Same applies to any flanged
joint / vessel connection of course.
FLANGE FACE FINISH
The ASME B16.5 code requires that the flange face (raised
face and flat face) has a specific roughness to ensure that
this surface be compatible with the gasket and provide a
high quality seal.
A serrated finish, either concentric or spiral, is required with
30 to 55 grooves per inch and a resultant roughness
between 125 and 500 micro inches. This allows for various
grades of surface finish to be made available by flange
manufactures for the gasket contact surface of metal
flanges.
THE MOST USED SURFACES ARE
Stock Finish
The most widely used of any flange surface finish, because practically, is suitable for all ordinary
service conditions. Under compression, the soft face from a gasket will embed into this finish, which
helps create a seal, and a high level of friction is generated between the mating surfaces. The finish
for these flanges is generated by a 1.6 mm radius round-nosed tool at a feed rate of 0.8 mm per

revolution up to 12 inch. For sizes 14 inch and larger, the finish is made with
3.2 mm round-nosed tool at a feed of 1.2 mm per revolution.
Spiral Serrated
This is also a continuous or phonographic spiral groove, but it differs from the
stock finish in that the groove typically is generated using a 90-deg tool which
creates a "V" geometry with 45° angled serration.
Concentric Serrated
As the name suggests, this finish is comprised of concentric grooves. A 90°
tool is used and the serrations are spaced evenly across the face.
Smooth Finish
This finish shows no visually apparent tool markings. These finishes are
typically utilized for gaskets with metal facings such as double jacketed, flat
steel and corrugated metal. The smooth surfaces mate to create a seal and
depend on the flatness of the opposing faces to effect a seal. This is typically
achieved by having the gasket contact surface formed by a continuous
(sometimes called phonographic) spiral groove generated by a 0.8 mm radius
round-nosed tool at a feed rate of 0.3 mm per revolution with a depth of 0.05
mm. This will result in a roughness between Ra 3.2 and 6.3 micrometers (125
- 250 micro inch).
GASKETS
To realize a leak-free flange connection gaskets are
necessary.
Gaskets are compressible sheets or rings used to make a
fluid-resistant seal between two surfaces. Gaskets are
built to operate under extreme temperature and pressures
and are available in a wide range of metallic, semi-metallic
and non-metallic materials.
The principle of sealing, for example, is the compression from a gasket between two flanges. A
gaskets fills the microscopic spaces and irregularities of the flange faces and then it forms a seal that
is designed to keep liquids and gases. Correct installation of damage free gaskets is a requirement for
a leak-free flange connection.
On this website gaskets according to ASME B16.20 (Metallic and semi-metallic gaskets for Pipe
flanges) and ASME B16.21 (Nonmetallic flat gaskets for pipe flanges) will be defined.

WHAT IS A FLANGE GASKET
Flange gaskets are used to create a static seal between two flanges faces, at various operating
conditions, with varied pressure and temperature ratings.
A gaskets fills the microscopic spaces and irregularities of the flange faces, and then it forms a seal
that is designed to keep liquids and gases.
Correct installation of damage-free gaskets and demage-free flange faces is a requirement for a leak-
free flange connection.
If it would be technically possible, in order to manufacture flanges perfectly flat and smooth, and
perfectly compatible with one another under all operating conditions, a gasket would not be
necessary.
But in normal practice it is not possible, because flange connections under ANY circumstances should
be made. Small impurities and a small bit of dirt, is in practice not be avoided and therefore it is
necessary to use a gasket.
TYPES OF GASKETS
Materials for gaskets can be divided into three main categories:
 Non-metallic types
 Semi-metallic types
 Metallic types
Non-metallic gaskets are usually
composite sheet materials are used with
flat-face and raised-face flanges in low
Pressure Class applications. Non-metallic
gaskets are manufactured from arimid
fiber, glass fiber, elastomer, Teflon (PTFE),
graphite etc.. Full-face gasket types are
suitable for use with flat-face flanges. Flat-ring gasket types are suitable for use with raised face
flanges.
ASME B16.21 covers types, sizes, materials, dimensions, dimensional tolerances, and markings for
non-metallic flat gaskets.
Semi-metallic gaskets are composites of metal and
non-metallic materials. The metal is intended to offer
strength and resiliency, while the non-metallic portion
provides conformability and sealability. Often used
semi-metallic gaskets are spiral wound and camprofile,
and a variety of metal-reinforced graphite gaskets.
Semi-metallic are designed for almost all operating

conditions and high-temperature and pressure applications, and are used on raised face, male-and-
female, and tongue-and-groove flanges.
ASME B16.20 covers materials, dimensions, dimensional tolerances, and markings for metallic and
semi-metallic gaskets.
Metallic gaskets are fabricated from
one or a combination of metals to the
desired shape and size. Often used
metallic gaskets are ring-type-joint
gaskets (RTJ). They are always applied
to special, accompanying flanges which
ensure good, reliable sealing with the
correct choice of profiles and material.
Ring Type Joint gaskets are designed to seal by "initial line contact" or wedging action between the
mating flange and the gasket. By applying pressure on the seal interface through bolt force, the
"softer" metal of the gasket flows into the microfine structure of the harder flange material, and
creating a very tight and efficient seal.
ASME B16.20 covers materials, dimensions, dimensional tolerances, and markings for metallic and
semi-metallic gaskets.
OFTEN USED SEMI-METALLIC
GASKETS
Here below you will find a short
description of a number of semi-
metallic gaskets, which are largely
used. For information on other
types, I refer to the World Wide
Web. There you can find a lot of
reliable information about gaskets.
Spiral wound gaskets
The spiral wound gasket meets the
most exacting conditions of both
temperature and pressure in
flanged joints and similar
assemblies and against every known corrosive and toxic media.

The spiral wound gasket depends upon the mechanical characteristics of a formed metal spiral strip,
rather than the compressive virtues of more traditional gasket materials. This makes it particularly
suitable for low or fluctuating bolt loads. The sealing strips, or fillers, are usually graphite, although
other materials such as Teflon (PTFE) may be used, the windings are always stainless steel. For this
type of gasket to work the spiral must not be over compressed, hence one of two types of
compression control is usually used.
The completed gasket is fitted into a steel ring of specific thickness. When the gasket is fitted into a
flange and the bolt load is applied, flange closure is governed by the outer steel ring of the gasket. To
further improve the pressure rating of the spiral wound gasket, a steel ring may be added to the
inside. This gives an additional compression limiting stop and provides a heat and corrosion barrier
protecting gasket windings and preventing flange erosion. It is customary to select inner ring material
to be the same as the metal winding.
ASME B16.20 which covers spiral wound gaskets requires the use of solid metal inner rings in:
Pressure Class 900, nominal pipe sizes 24 and larger, Pressure Class 1500 from nominal pipe sizes 12
and larger, Pressure Class 2500 from nominal pipe sizes 4 and larger and all PTFE filled gaskets. In
the same standard is also described how a spiral wound gasket should be characterized, below you will
find an image on it.
Camprofile gaskets
Camprofile or "Grooved" gaskets have proven themselves in all industrial applications. Camprofile
gaskets are found in industrial power plants and in the primary circuits in nuclear installations. Used
either between flanges or in heat exchanger units in nuclear applications. The Petro and chemical
industry benefit too, as the gaskets are used in applications where high pressures and temperatures
are maintained and consequently high bolt loads need to be controlled.
Camprofile gaskets consist of a metal core (generally Stainless Steel) with concentric grooves on
either side with sealing materials. The sealing layers (depending on the service duty) can be Graphite,
PTFE (Teflon), CAF or Metal (e.g. Aluminium or Silver). Camprofile's can be used without sealing
layers to provide an excellent seal but there is a risk of flange surface damage - especially at high
seating loads. The sealing layers protect the flange surfaces from damage in addition to providing an
effective seal. In the main Menu "Others" you will find a link to the dimensions of that kind of grooved
gasket.
Metal jacketed gaskets
Metal Jacketed gaskets, as the name suggests, are comprised of a metallic outer shell with either a
metallic or non-metallic filler. The filler material gives the gasket resilience, while the metal jacket
protects the filler and resists pressures, temperatures and corrosion.

They are traditionally used for heat exchanger applications, pumps and valves, however the resilience
and recovery properties of these gaskets are limited. Metal Jacketed gaskets require smooth flange
surface finishes, high bolt loads and flange flatness in order to seal effectively.
There are many different styles of jacketed gaskets available. In the main Menu "Others" you will find
a link to the dimensions of double jacketed flange gaskets. In that type the filler material is completely
enclosed by a two piece metal jacket, which covers both the inside and outside diameters and both
contact surfaces.
BOLTS
To connect two flanges with each other, also bolts are necessary.
The quantity will be given by the number of bolt holes in a flange, diameter and length of bolts is
dependent of flange type and Pressure Class of flange.
The most used bolts in Petro and chemical industry for ASME B16.5 flanges are stud bolts. Stud bolts
are made from a threaded rod and using two nuts. The other available type is the machine bolt that
using one nut. On this site only stud bolts will be discussed.
Dimensions, dimensional tolerances etc. have been defined in the ASME B16.5 and ASME 18.2.2
standard, materials in different ASTM standards.
TYPES OF BOLTS
In Petro and chemical industry for flange connections actually only stud bolts are used, but in
principle, two types of bolts for flange connections are available.
1. Stud bolt
2. Hex bolt
The stud bolt is a threaded rod with 2 heavy hexagon nuts, while the hex bolt has a head with one
nut. Nuts and head are both six sided.
STUD BOLT GENERAL
Stud bolt length are defined in
ASME B16.5 standard. The length in
inches is equal to the effective
thread length measured parallel to
the axis, from the first to the first
thread without the chamfers
(points). First thread is defined as
the intersection of the major
diameter of the thread with the base
of the point.

Note: The length of metric stud bolts measured parallel to axis, is the distance from each stud bolt,
including the point.
The quantity of bolts for a flange connection will be given by the number of bolt holes in a flange,
diameter and length of bolts is dependent of flange type and Pressure Class of flange.
To allow the use of hydraulic tensioning equipment, larger dimension studs shall be often one
diameter longer than "standard". That bolts to have plastic end cap protection.
Bolts threading are defined in ASME B1.1 Unified Inch Screw Threads, (UN and UNR Thread Form).
The most common thread is a symmetrical form with a V-profile. The included angle is 60°. This form
is widely used in the Unified thread (UN, UNC, UNF, UNRC, UNRF) form as the ISO / metric threads.
The advantage of a symmetrical threads is that they are easier to produce and inspect compared with
non-symmetrical threads. These are typically used in general-purpose fasteners.
Thread series cover designations of diameter/pitch combinations that are measured by the number of
threads per inch (TPI) applied to a single diameter.
Standard Thread Pitches
 Coarse thread series (UNC/UNRC) is the most widely used thread system and applied in most of
the screws, bolts and nuts. Coarse threads are used for threads in low strength materials such as
iron, mild steel, copper and softer alloy, aluminium, etc.. The coarse thread is also more tolerant in
adverse conditions and facilitate quick assembly.
 Fine thread series (UNF/UNRF) is commonly used in precision applications and in there where
require a higher tensile strength than the coarse thread series.
 8 - Thread series (8UN) is the specified thread forming method for several ASTM standards
including A193 B7, A193 B8/B8M, and A320. This series is mostly used for diameters one inch and
above.
Hex nuts (dimensional data) are defined in ASME B18.2.2, and even as bolts the threading in ASME
B1.1.
Depending on a customer specification, nuts must be both sites chamfered or with on one side a
washer-face.
The height of a nut for stud bolts are the same as the diameter of the thread rod.

IMAGE of a both sites chamfered nut.
MARKING OF STUDBOLTS
Thread rods and nuts must be marked by the manufacturer with a unique identifier to identify the
manufacturer or private label distributor, as appropriate. Below you will find a number of ASTM
examples.
MATERIALS FOR STUDBOLTS
Dimensions from stud bolts are defined in the ASME B16.5 standard. The material qualities for studs
are defined in the different ASTM standards, and are indicated by Grade. Frequently used grades are
A193 for thread rods and A194 for the nuts.
ASTM A193 covers alloy and stainless steel bolting material for pressure vessels, valves, flanges, and
fittings for high temperature or high pressure service, or other special purpose applications.
ASTM A194 covers a variety of carbon, alloy, and martensitic and austenitic stainless steel nuts. These
nuts are intended for high-pressure or high-temperature service, or both.
Below you will find as an example a table with materials and grades for flanges, thread rods (bolts)
and nuts, arranged on design temperature, flanges, thread rods and recommended nuts.
IMAGE of a nut with on one side a
washer-face.

DESIGN
TEMPERATURE
FLANGES GRADE THREAD RODS GRADE NUTS
-195° to 102°C
ASTM A 182
Gr. F304, F304L, F316,
F316L, F321, F347
A320 Gr. B8 Class 2 A194 Gr. 8A
-101° to -47°C
ASTM A 350
Gr. LF3
A 320 Gr. L7 A 194 Gr. 7
-46° to -30°C
ASTM A 350
Gr. LF2
A 320 Gr. L7 A 194 Gr. 7
-29° to 427°C ASTM A 105 A 193 Gr. B7 A 194 Gr. 2H
428° to 537°C
ASTM A 182
Gr. F11, F22
A 193 Gr. B16 A 194 Gr. 2H
538° to 648°C
ASTM A182
Gr. F11, F22
A 193 Gr. B8 Class 1 A 194 Gr. 8A
649° to 815°C
ASTM A182
Gr. F304 H, F316 H
A 193 Gr. B8 Class 1 A 194 Gr. 8A
Note: materials in the table above are being provided for guidance purposes

WHAT ARE SPECIAL FLANGES
On this page are the special flanges discussed, and parts that may include a flange connection. Special
Flanges are basically identical to standard flanges, but have a number of special features.
ORIFICE FLANGE
Orifice Flanges are intended for use instead of standard pipe flanges when an orifice plate or flow
nozzle must be installed. Pairs of pressure "Tappings", mostly on 2 sides, directly opposite each other,
are machined into the orifice flange. This makes separate orifice carriers or tappings in the pipe wall
unnecessary.
On the image above a set Orifice Flanges is
shown, where the tappings are sealed with a plug,
and where a jack screw is machined. This jack
screw is used to facilitate separating the flanges
for inspection or replacement of the "Orifice Plate"
and gaskets.
The range of orifice flanges covers all standard
sizes and ranges, and all common flange
materials. Flanges are available in Welding Neck,
Slip On, and Threaded form, and are typically
supplied with two ½" NPT tappings in each flange.
ASME B16.36 covers Dimensions and
dimensional tolerances from orifice flanges
(similar to those covered in ASME B16.5) that
have orifice pressure differential connections.
Coverage is limited to the following flanges:
 Welding Neck Classes 300, 400, 600, 900,
1500, 2500
 Slip On Class 300
 Threaded Class 300
ORIFICE PLATE
An Orifice Plate is typically a circular, flat plate with a handle. The most common orifice plate is the
square-edged concentric bored orifice plate, others are Eccentric Orifice Plate, Segmental Orifice Plate
etc. and typically, it is made of a durable metal such as stainless steel.
The American National Pipe Thread Tapered
NPT is the best known and most widely used connection where the pipe
thread provides both the mechanical joint and the hydraulic seal. NPT has
a tapered male and female thread which seals with Teflon tape or jointing
compound.
ASME B1.20.1 covers dimensions and gaging of NPT pipe threads for
general purpose applications.

They are normally mounted between a set of Orifice Flanges and are installed in
a straight run of smooth pipe to avoid disturbance of flow patterns from fittings
and valves.
The image of a CROSS-SECTION
of a set of Orifice Flanges, gives you a
good impression.
Orifices Plates are used to create a
differential pressure that relates to
the velocity of the gas from which a
flow rate can be calculated. As the
following gas passes through the
restriction in the line caused by the
orifice plate, the difference in the
upstream and downstream pressure can be
measured at set points, called taps, and a flow rate at
the point can be determined. As the plate serve as a
restriction in a pipeline, then we talk about a Restriction Orifice Plate, abbreviated (RO).
Concentric Orifice Plate
The most common orifice plate is the square-edged concentric bored orifice plate. The concentric
bored orifice plate is the dominant design because of its proven reliability in a variety of applications
and the extensive amount of research conducted on this design. The concentric plate is also easily
reproduced at a relatively low cost.
The concentric orifice is used to measure a wide variety of single phase, liquid and gas products,
typically in conjunction with flange taps.
Eccentric Orifice Plate
Eccentric orifices are used to measure the flow fluids that carry solids and are also used to measure
gases which carry liquids. With the eccentric orifice at the top of the plate, it can measure liquids that
carry gas. It should be noted that the eccentric orifice has a higher degree of uncertainty as compared
to the concentric orifice.
Segmental Orifice Plate
Segmental orifice plates are used to measure the flow of light slurries and fluids with high
concentration of solids. The design of segmental orifice eliminates the damming of foreign matter and
provides more complete drainage than the eccentric orifice plate. The segmental orifice is considerably
more expensive than the eccentric orifice and has slightly greater uncertainty.
1. Orifice Plate 2. Hole in Plate
3. Tappings 4. Orifice flange

SPECTACLE BLINDS
Spectacle Blinds are generally applied to permanently separating pipe systems, or just to connect with
each other.
A Spectacle Blind is a steel
plate cut into two discs of a
certain thickness.
The two discs are attached to
each other by section of steel
similar to the nose piece of a
pair of glasses. One of the
discs is a solid plate, and the
other is a ring, whose inside
diameter is equal to that of a
flange.
Spectacle Blinds be applied in
systems, which regularly need
to be separated from other
installations.
Normally, a Spectacle Blind is mounted in the "open" position so that flow through the pipe is possible.
If the Spectacle Blind in the "close" position is rotated, the pipe is blanked off and no flow is possible.
Maintenance on a pipe system can be a reason to rotate the spectacle in the "close" position. This run
will take place through the hole that is drilled in the connection piece. By loosening of all bolts, and
partial removal of their, the Spectacle Blind can be rotated. After replacing the gaskets (new gaskets
are to recommend), the bolts can be re-assembled and tightened.
SPADES (SINGLE BLINDS) / RING SPACER
Spades and Ring Spacers are basically the same as Spectacle Blinds, except that both are not
attached to each other.

Spades and Spacers are applied in systems where maintenance is often not necessary, or in
applications with large pipe sizes. Depending on the flange size and the Pressure Class, Spades can
weigh hundreds of pounds. To prevent unnecessary weight to a flange connection, usually will be
chosen not for a Spectacle Blind, but for 2 separate parts.
So as for the Spectacle Blind already described, maintenance on a pipe system can be a reason to
temporarily replace a Ring Spacer for a Spade. By loosening of all bolts, and half of the bolts
temporarily remove, the Spade or Spacer can be placed. After replacing the gaskets (new gaskets are
to recommend), the bolts can be re-assembled and tightened.
A small problem is that we basically cannot see, or a Spade or a Spacer mounted between the flanges.
Therefore the handles are often specially marked, or both have a different design; a customer often
provides its own specification.
What should never lack is, that in the handle, the diameter and the Pressure Class of a Spade or
Spacer is engraved; this applies also for the Spectacle Blind.
SURFACES / DIMENSIONS / MATERIAL
The sealing surfaces of a Spectacle Blind, Spade or Ring Spacer are usually conducted in accordance
with the Face Finish from the flange. The diameter always is slightly larger than the Raised Face of a
flange; by a correct assembly, the bolts are just not touched by the Blind or Spacer.
The diameter of them is depending on the flange size, and the thickness from the Pressure Class of a
flange.
Dimensions from Spectacle Blinds, Spades and Ring Spacers, you will find in the main Menu "Flanges"
ASME B16.48 covers pressure-temperature ratings, materials, dimensions, dimensional tolerances,
marking, and testing for operating line blanks in sizes NPS 1/2 up to NPS 24 for installation between
ASME B16.5 flanges in the 150, 300, 600, 900, 1500, and 2500 Pressure Classes.
Spectacle Blinds, Spades and Ring Spacers should be made from a plate or forging specification,
approved for use by ASME B31.3, of essentially the same chemical composition as the mating flanges
and piping involved.
LONG WELDING NECK FLANGE
Long Neck Welding (abbreviated LWN) flanges are similar to a
standard Welding Neck flange, but the "Neck" is considerably longer.
This type is often used as a nozzle for a barrel or column. In addition,
there are the type LWN Heavy Barrel (HB) and the Equal LWN Barrel
(E); they have a different shape and a thicker "Wall".

WELDOFLANGE / NIPOFLANGE
The Weldoflange and Nipoflange is a combination of a Welding Neck flange and a supposedly Weldolet
or Nipolet. The 2 components are manufactured in one piece, and not welded. These flanges are
primarily in Branchconnections.
On the website of Promat BD you can find more information about the various performances,
dimensions etc.. Furthermore, they have an expanded range of special flanges, fittings and branch
connections.
EXPANDER FLANGE
Expander Flanges is a Welding Neck pipe flange where
the nominal size of the non-flanged end is larger than
the nominal size of the flanged end. They can be used
to change the size of a pipe run. These are usually
used to increase the line size to the first or second
larger size. This is an alternative to using a separate
reducer and weld neck flange combination. The
expander flange can be used to connect pipe to pumps,
compressors and valves.
REDUCING FLANGE
Reducing Flanges are suitable for changing line size, but
should not be used if abrupt transition would create
undesirable turbulence, as at pump connections. A
reducing flange consists of a flange with one specified
diameter having a bore of a different and smaller,
diameter. Except for the bore and hub dimensions, the
flange will have dimensions of the larger pipe size.

Method for calculating Stud bolt lengths
The stud bolt theoretical length can be calculated by means of the formula:
L = 2 (s + n + h + rf) + g
 s = free threads (equals 1/3 time bolt diameter)
 n = nut thickness (equals nominal bolt diameter)
 h = flange thickness
 rf = height of raised face
for class 150 and class 300 height of raised face is included in h height
 g = gasket thickness approximately 3 mm

Dimensions Stud bolts for RF and RTJ flanges acc to ASME B16.5
Pressure Class 150 - NPS 1/2 up to NPS 24
NPS
Diameter
of bolts (inches)
Length
RF
Length
RTJ
N°
of bolts
1/2 1/2 55 - 4
3/4 1/2 65 - 4
1 1/2 65 75 4
1 ¼ 1/2 70 85 4
1 ½ 1/2 70 85 4
2 5/8 85 95 4
2 ½ 5/8 90 100 4
3 5/8 90 100 4
3 ½ 5/8 90 100 8
4 5/8 90 100 8
5 3/4 95 110 8
6 3/4 100 115 8
8 3/4 110 120 8
10 7/8 115 125 12
12 7/8 120 135 12
14 1 135 145 12
16 1 135 145 16
18 1 1/8 145 160 16
20 1 1/8 160 170 20
24 1 1/4 170 185 20
General notes:
 Dimensions are in millimeters unless otherwise indicated.
 The length of the stud bolt does not include the height of the CHAMFERS (points).
 Length dimensional tolerances for all stud bolts:
length to 12 inch tolerance = ± 1.6 mm
length over 12 inch to 18 inch tolerance = ± 3.2 mm
length over 18 inch tolerance = ± 6.4 mm

NPS
Diameter
of bolts (inches)
Length
RF
Length
RTJ
N°
of bolts
1/2 1/2 65 75 4
3/4 5/8 75 90 4
1 5/8 75 90 4
1 ¼ 5/8 85 95 4
1 ½ 3/4 90 100 4
2 5/8 90 100 8
2 ½ 3/4 100 115 8
3 3/4 110 120 8
3 ½ 3/4 110 125 8
4 3/4 115 125 8
5 3/4 120 135 8
6 3/4 120 140 12
8 7/8 140 150 12
10 1 160 170 16
12 1 1/8 170 185 16
14 1 1/8 180 190 20
16 1 1/4 190 205 20
18 1 1/4 195 210 24
20 1 1/4 205 220 24
24 1 1/2 230 255 24
General notes:

NPS
Diameter
of bolts (inches)
Length
RF
Length
RTJ
N°
of bolts
1/2 1/2 75 75 4
3/4 5/8 90 90 4
1 5/8 90 90 4
1 ¼ 5/8 95 95 4
1 ½ 3/4 110 110 4
2 5/8 110 110 8
2 ½ 3/4 120 120 8
3 3/4 125 125 8
3 ½ 7/8 140 140 8
4 7/8 140 140 8
5 7/8 145 145 8
6 7/8 150 150 12
8 1 170 170 12
10 1 1/8 190 190 16
12 1 1/4 205 205 16
14 1 1/4 210 210 20
16 1 3/8 220 220 20
18 1 3/8 230 230 24
20 1 1/2 240 250 24
24 1 3/4 265 280 24
General notes:

NPS
Diameter
of bolts (inches)
Length
RF
Length
RTJ
N°
of bolts
1/2 1/2 75 75 4
3/4 5/8 90 90 4
1 5/8 90 90 4
1 ¼ 5/8 95 95 4
1 ½ 3/4 110 110 4
2 5/8 110 110 8
2 ½ 3/4 120 120 8
3 3/4 125 125 8
3 ½ 7/8 140 140 8
4 1 145 145 8
5 1 1/8 165 165 8
6 1 1/8 170 170 12
8 1 1/4 190 195 12
10 1 3/8 215 215 16
12 1 3/8 220 220 20
14 1 1/2 235 235 20
16 1 5/8 255 255 20
18 1 3/4 275 275 20
20 1 3/4 285 290 24
24 2 330 335 24
General notes:

NPS
Diameter
of bolts (inches)
Length
RF
Length
RTJ
N°
of bolts
1/2 3/4 110 110 4
3/4 3/4 115 115 4
1 7/8 125 125 4
1 ¼ 7/8 125 125 4
1 ½ 1 140 140 4
2 7/8 145 145 8
2 ½ 1 160 160 8
3 7/8 145 145 8
4 1 1/8 170 170 8
5 1 1/4 190 190 8
6 1 1/8 190 195 12
8 1 3/8 220 220 12
10 1 3/8 235 235 16
12 1 3/8 255 255 20
14 1 1/2 275 280 20
16 1 5/8 285 290 20
18 1 7/8 325 335 20
20 2 350 360 20
24 2 1/2 440 455 20
General notes:

NPS
Diameter
of bolts (inches)
Length
RF
Length
RTJ
N°
of bolts
1/2 3/4 110 110 4
3/4 3/4 115 115 4
1 7/8 125 125 4
1 ¼ 7/8 125 125 4
1 ½ 1 140 140 4
2 7/8 145 145 8
2 ½ 1 160 160 8
3 1 1/8 180 180 8
4 1 1/4 195 195 8
5 1 1/2 250 250 8
6 1 3/8 260 265 12
8 1 5/8 290 300 12
10 1 7/8 335 345 12
12 2 375 385 16
14 2 1/4 405 425 16
16 2 1/2 445 470 16
18 2 3/4 495 525 16
20 3 540 565 16
24 3 1/2 615 650 16
General notes:

NPS
Diameter
of bolts (inches)
Length
RF
Length
RTJ
N°
of bolts
1/2 3/4 120 120 4
3/4 3/4 125 125 4
1 7/8 140 140 4
1 ¼ 1 150 150 4
1 ½ 1 1/8 170 170 4
2 1 180 180 8
2 ½ 1 1/8 195 205 8
3 1 1/4 220 230 8
4 1 1/2 255 260 8
5 1 3/4 300 310 8
6 2 345 355 8
8 2 380 395 12
10 2 1/2 490 510 12
12 2 3/4 540 560 12
General notes:

ASTM GRADES
Dimensions from carbon steel and stainless steel flanges are defined in the ASME B16.5 standard. The
material qualities for these flanges are defined in the ASTM standards.
These ASTM standards, define the specific manufacturing process of the material and determine the
exact chemical composition of pipes, fittings and flanges, through percentages of the permitted
quantities of carbon, magnesium, nickel, etc., and are indicated by "Grade".
For example, a carbon steel flange can be identified with Grade F9 or F11, a stainless-steel flange with
Grade F316 or Grade F321 etc..
Below you will find as an example a table with chemical requirements for flanges according to ASTM
A182 Grade F304, F304L, F316L, and a table with frequent Grades, arranged on pipe and pipe-
components, which belong together as a group.
As you may be have noted, in the table below, ASTM A105 has no Grade. Sometimes ASTM A105N is
described;
"N" stands not for Grade, but for normalized. Normalizing is a type of heat treatment, applicable to
ferrous metals only. The purpose of normalizing is to remove the internal stresses induced by heat
treating, casting, forming etc..
Chemical requirements composition, %
Grade F304 (A) Grade F304L (A) Grade F316L (A)
Carbon, max 0.08 0.035 0.035
Manganese, max 2.00 2.00 2.00
Phosphorus, max 0.045 0.045 0.045
Sulfur, max 0.030 0.030 0.030
Silicon, max 1.00 1.00 1.00
Nickel 8 - 11 8 - 13 10 - 15
Chrome 18 - 20 18 - 20 16 - 18
Molybdenum - - 2.00-3.00
(A) Nitrogen 0.10% max.

ASTM Grades
Material Pipes Fittings Flanges Valves Bolts & Nuts
Carbon Steel
A106 Gr A A234 Gr WPA A105 A216 Gr WCB
A193 Gr B7
A194 Gr 2H
A106 Gr B A234 Gr WPB A105 A216 Gr WCB
A106 Gr C A234 Gr WPC A105 A216 Gr WCB
Carbon Steel
Alloy
High-Temp
A335 Gr P1 A234 Gr WP1 A182 Gr F1 A217 Gr WC1
A193 Gr B7
A194 Gr 2H
A335 Gr P5 A234 Gr WP5 A182 Gr F5 A217 Gr C5
A335 Gr P9 A234 Gr WP9 A182 Gr F9 A217 Gr C12
Carbon Steel
Alloy
Low-Temp
A333 Gr 5 A420 Gr WPL6 A350 Gr LF2 A352 Gr LCB
A320 Gr L7
A194 Gr 7A333 Gr 3 A420 Gr WPL3 A350 Gr LF3 A352 Gr LC3
Austenitic
Stainless
Steel
A312 Gr TP304 A403 Gr WP304 A182 Gr F304 A182 Gr F304
A193 Gr B8
A194 Gr 8
MATERIALS ACCORDING TO ASTM
Pipes
 A106 = This specification covers carbon steel pipe for high-temperature service.
 A335 = This specification covers seamless ferritic alloy-steel pipe for high-temperature service.
 A333 = This specification covers wall seamless and welded carbon and alloy steel pipe intended for
use at low temperatures.
 A312 = Standard specification for seamless, straight-seam welded, and cold worked welded
austenitic stainless steel pipe intended for high-temperature and general corrosive service.
Fittings
 A234 = This specification covers wrought carbon steel and alloy steel fittings of seamless and
welded construction.
 A420 = Standard specification for piping fittings of wrought carbon steel and alloy steel for low-
temperature service.
 A403 = Standard specification for wrought austenitic stainless steel piping fittings.

Flanges
 A105 = This specification covers standards for forged carbon steel piping components, that is,
flanges, fittings, valves, and similar parts, for use in pressure systems at ambient and higher-
temperature service conditions.
 A182 = This specification covers forged or rolled alloy and stainless steel pipe flanges, forged
fittings, and valves and parts for high-temperature service.
 A350 = This specification covers several grades of carbon and low alloy steel forged or ring-rolled
flanges, forged fittings and valves for low-temperature service.
Valves
 A216 = This specification covers carbon steel castings for valves, flanges, fittings, or other
pressure-containing parts for high-temperature service and of quality suitable for assembly with
other castings or wrought-steel parts by fusion welding.
 A217 = This specification covers steel castings, martensitic stainless steel and alloys steel castings
for valves, flanges, fittings, and other pressure-containing parts intended primarily for high-
temperature and corrosive service.
 A352 = This specification covers steel castings for valves, flanges, fittings, and other pressure-
containing parts intended primarily for low-temperature service.
 A182 = This specification covers forged or rolled alloy and stainless steel pipe flanges, forged
fittings, and valves and parts for high-temperature service.
Bolds & Nuts
 A193 = This specification covers alloy and stainless steel bolting material for pressure vessels,
valves, flanges, and fittings for high temperature or high pressure service, or other special purpose
applications.
 A320 = Standard Specification for Alloy-Steel and Stainless Steel Bolting Materials for Low-
Temperature Service.
 A194 = Standard specification for nuts in many different material types.

Dimensions Slip On flanges and Stud bolts according to ASME B16.5
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 30 38 38 38 38 38 -
Diameter - D 90 95 95 95 120 120 -
Thickness - B
9.6
11.2
12.7
14.3
14.3
20.7
14.3
20.7
22.3
28.7
22.3
28.7
-
Diameter - G 35.1 35.1 35.1 35.1 35.1 35.1 -
Diameter - K 60.3 66.7 66.7 66.7 82.6 82.6 -
Height - H
14
15.6
21
22.6
22
28.4
22
28.4
32
38.4
32
38.4
-
Bolt Holes 4 4 4 4 4 4 -
Diameter - L 15.9 15.9 15.9 15.9 22.2 22.2 -
Stud bolt
Dia x Length
1/2"
55
1/2"
65
1/2"
75
1/2"
75
3/4"
110
3/4"
110
-
-
Nominal Pipe Size 1/2 ID = 22.3
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 38 48 48 48 44 44 -
Diameter - D 100 115 115 115 130 130 -
Thickness - B
11.2
12.8
14.3
15.9
15.9
22.3
15.9
22.3
25.4
31.8
25.4
31.8
-
Diameter - G 42.9 42.9 42.9 42.9 42.9 42.9 -
Diameter - K 69.9 82.6 82.6 82.6 88.9 88.9 -
Height - H
14
15.6
24
25.6
25
31.4
25
31.4
35
41.4
35
41.4
-
Bolt Holes 4 4 4 4 4 4 -
Diameter - L 15.9 19.1 19.1 19.1 22.2 22.2 -
Stud bolt
Dia x Length
1/2"
65
5/8"
75
5/8"
90
5/8"
90
3/4"
115
3/4"
115
-
-
Nominal Pipe Size 3/4 ID = 27.7

Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 49 54 54 54 52 52 -
Diameter - D 110 125 125 125 150 150 -
Thickness - B
12.7
14.3
15.9
17.5
17.5
23.9
17.5
23.9
28.6
35
28.6
35
-
Diameter - G 50.8 50.8 50.8 50.8 50.8 50.8 -
Diameter - K 79.4 88.9 88.9 88.9 101.6 101.6 -
Height - H
16
17.6
25
26.6
27
33.4
27
33.4
41
47.4
41
47.4
-
Bolt Holes 4 4 4 4 4 4 -
Diameter - L 15.9 19.1 19.1 19.1 25.4 25.4 -
Stud bolt
Dia x Length
1/2"
65
5/8"
75
5/8"
90
5/8"
90
7/8"
125
7/8"
125
-
-
Nominal Pipe Size 1 ID = 34.5
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 59 64 64 64 64 64 -
Diameter - D 115 135 125 135 160 160 -
Thickness - B
14.3
15.9
17.5
19.1
20.7
27.1
20.7
27.1
28.6
35
28.6
35
-
Diameter - G 63.5 63.5 63.5 63.5 63.5 63.5 -
Diameter - K 88.9 98.4 98.4 98.4 111.1 111.1 -
Height - H
19
20.6
25
26.6
29
35.4
29
35.4
41
47.4
41
47.4
-
Bolt Holes 4 4 4 4 4 4 -
Diameter - L 15.9 19.1 19.1 19.1 25.4 25.4 -
Stud bolt
Dia x Length
1/2"
70
5/8"
85
5/8"
95
5/8"
95
7/8"
125
7/8"
125
-
-
Nominal Pipe Size 1¼ ID = 43.2
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 65 70 70 70 70 70 -
Diameter - D 125 155 155 155 180 180 -
Thickness - B
15.9
17.5
19.1
20.7
22.3
28.7
22.3
28.7
31.8
38.2
31.8
38.2
-
Diameter - G 73.2 73.2 73.2 73.2 73.2 73.2 -
Diameter - K 98.4 114.3 114.3 114.3 123.8 123.8 -
Height - H
21
22.6
29
30.6
32
38.4
32
38.4
44
50.4
44
50.4
-
Bolt Holes 4 4 4 4 4 4 -
Diameter - L 15.9 22.2 22.2 22.2 28.6 28.6 -
Stud bolt
Dia x Length
1/2"
70
3/4"
90
3/4"
110
3/4"
110
1"
140
1"
140
-
-
Nominal Pipe Size 1½ ID = 49.5
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 78 84 84 84 105 105 -
Diameter - D 150 165 165 165 215 215 -
Thickness - B
17.5
19.1
20.7
22.3
25.4
31.8
25.4
31.8
38.1
44.5
38.1
44.5
-
Diameter - G 91.9 91.9 91.9 91.9 91.9 91.9 -

Diameter - K 120.7 127 127 127 165.1 165.1 -
Height - H
24
25.6
32
33.6
37
43.4
37
43.4
57
63.4
57
63.4
-
Bolt Holes 4 8 8 8 8 8 -
Diameter - L 19.1 19.1 19.1 19.1 25.4 25.4 -
Stud bolt
Dia x Length
5/8"
85
5/8"
90
5/8"
110
5/8"
110
7/8"
145
7/8"
145
-
-
Nominal Pipe Size 2 ID = 62
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 90 100 100 100 124 124 -
Diameter - D 180 190 190 190 245 245 -
Thickness - B
20.7
22.3
23.9
25.5
28.6
35
28.6
35
41.3
47.7
41.3
47.7
-
Diameter - G 104.6 104.6 104.6 104.6 104.6 104.6 -
Diameter - K 139.7 149.2 149.2 149.2 190.5 190.5 -
Height - H
27
28.6
37
38.6
41
47.4
41
47.4
64
70.4
64
70.4
-
Bolt Holes 4 8 8 8 8 8 -
Diameter - L 19.1 22.2 22.2 22.2 28.6 28.6 -
Stud bolt
Dia x Length
5/8"
90
3/4"
100
3/4"
120
3/4"
120
1"
160
1"
160
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 108 117 117 117 127 - -
Diameter - D 190 210 210 210 240 - -
Thickness - B
22.3
23.9
27
28.6
31.8
38.2
31.8
38.2
38.1
44.5
- -
Diameter - G 127 127 127 127 127 - -
Diameter - K 152.4 168.3 168.3 168.3 190.5 - -
Height - H
29
30.6
41
42.6
46
52.4
46
52.4
54
60.4
- -
Bolt Holes 4 8 8 8 8 - -
Diameter - L 19.1 22.2 22.2 22.2 25.4 - -
Stud bolt
Dia x Length
5/8"
90
3/4"
110
3/4"
125
3/4"
125
7/8"
145
-
-
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 122 133 133 133 - - -
Diameter - D 215 230 230 230 - - -
Thickness - B
22.3
23.9
28.6
30.2
35
41.4
35
41.4
- - -
Diameter - G 139.7 139.7 139.7 139.7 - - -
Diameter - K 177.8 184.2 184.2 184.2 - - -
Height - H
30
31.6
43
44.6
49
55.4
49
55.4
- - -
Bolt Holes 8 8 8 8 - - -
Diameter - L 19.1 22.2 25.4 25.4 - - -
Stud bolt
Dia x Length
5/8"
90
3/4"
110
7/8"
140
7/8"
140
-
-
-
-
-
-

Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 135 146 146 152 159 - -
Diameter - D 230 255 254 275 290 - -
Thickness - B
22.3
23.9
30.2
31.8
35
41.4
38.1
44.5
44.5
50.9
- -
Diameter - G 157.2 157.2 157.2 157.2 157.2 - -
Diameter - K 190.5 200 200 215.9 235 - -
Height - H
32
33.6
46
47.6
51
57.4
54
60.4
70
76.4
- -
Bolt Holes 8 8 8 8 8 - -
Diameter - L 19.1 22.2 25.4 25.4 31.8 - -
Stud bolt
Dia x Length
5/8"
90
3/4"
115
7/8"
140
7/8"
145
1 1/8"
170
-
-
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 192 206 206 222 235 - -
Diameter - D 280 320 320 355 380 - -
Thickness - B
23.9
25.5
35
36.6
41.3
47.7
47.7
54.3
55.6
62
- -
Diameter - G 215.9 215.9 215.9 215.9 215.9 - -
Diameter - K 241.3 269.9 269.9 292.1 317.5 - -
Height - H
38
39.6
51
52.6
57
63.4
67
73.4
86
92.4
- -
Bolt Holes 8 12 12 12 12 - -
Diameter - L 22.2 22.2 25.4 28.6 31.8 - -
Stud bolt
Dia x Length
3/4"
100
3/4"
120
7/8"
150
1"
170
1 1/8"
190
-
-
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 246 260 260 273 298 - -
Diameter - D 345 380 381 420 470 - -
Thickness - B
27
28.6
39.7
41.3
47.7
54.1
55.6
62
63.5
69.9
- -
Diameter - G 269.7 269.7 269.7 269.7 269.7 - -
Diameter - K 298.5 330.2 330 349.2 393.7 - -
Height - H
43
44.6
60
61.6
68
74.4
76
82.4
102
108.4
- -
Bolt Holes 8 12 12 12 12 - -
Diameter - L 22.2 22.2 28.6 31.8 38.1 - -
Stud bolt
Dia x Length
3/4"
110
7/8"
140
1"
170
1 1/8"
190
1 3/8"
220
-
-
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 305 321 321 343 368 - -
Diameter - D 405 445 445 510 545 - -
Thickness - B
28.6
30.2
46.1
47.7
54
60.4
63.5
69.9
69.9
76.3
- -
Diameter - G 323.9 323.9 323.9 323.9 323.9 - -

Diameter - K 362 387.4 387.4 431.8 469.9 - -
Height - H
48
49.6
65
66.6
73
79.4
86
92.4
108
114.4
- -
Bolt Holes 12 16 16 16 16 - -
Diameter - L 25.4 25.4 31.8 34.9 38.1 - -
Stud bolt
Dia x Length
7/8"
115
1"
160
1 1/8"
190
1 1/4"
215
1 3/8"
235
-
-
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 365 375 375 400 419 - -
Diameter - D 485 520 520 560 610 - -
Thickness - B
30.2
31.8
49.3
50.9
57.2
63.4
66.7
73.1
79.4
85.8
- -
Diameter - G 381 381 381 381 381 - -
Diameter - K 431.8 450.8 450.8 489 533.4 - -
Height - H
54
55.6
71
72.6
79
85.4
92
98.4
117
123.4
- -
Bolt Holes 12 16 16 20 20 - -
Diameter - L 25.4 28.6 34.9 34.9 38.1 - -
Stud bolt
Dia x Length
7/8"
120
1 1/8"
170
1 1/4"
205
1 1/4"
220
1 3/8"
255
-
-
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 400 425 425 432 451 - -
Diameter - D 535 585 585 605 640 - -
Thickness - B
33.4
35
52.4
54
60.4
66.8
69.9
76.3
85.8
92.2
- -
Diameter - G 412.8 412.8 412.8 412.8 412.8 - -
Diameter - K 476.3 514.4 514.4 527 558.8 - -
Height - H
56
57.6
75
76.6
84
90.4
94
100.4
130
136.4
- -
Bolt Holes 12 20 20 20 20 - -
Diameter - L 28.6 31.8 34.9 38.1 41.3 - -
Stud bolt
Dia x Length
1"
135
1 1/8"
180
1 1/4"
210
1 3/8"
235
1 1/2"
275
-
-
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 400 425 425 432 451 - -
Diameter - D 535 585 585 605 640 - -
Thickness - B
33.4
35
52.4
54
60.4
66.8
69.9
76.3
85.8
92.2
- -
Diameter - G 412.8 412.8 412.8 412.8 412.8 - -
Diameter - K 476.3 514.4 514.4 527 558.8 - -
Height - H
56
57.6
75
76.6
84
90.4
94
100.4
130
136.4
- -
Bolt Holes 12 20 20 20 20 - -
Diameter - L 28.6 31.8 34.9 38.1 41.3 - -
Stud bolt
Dia x Length
1"
135
1 1/8"
180
1 1/4"
210
1 3/8"
235
1 1/2"
275
-
-
-
-

Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 457 483 483 495 508 - -
Diameter - D 595 650 650 685 705 - -
Thickness - B
35
36.6
55.6
57.2
63.5
69.9
76.2
82.6
88.9
95.3
- -
Diameter - G 469.9 469.9 469.9 469.9 469.9 - -
Diameter - K 539.8 571.5 571.5 603.2 616 - -
Height - H
62
63.6
81
82.6
94
100.4
106
112.4
133
139.4
- -
Bolt Holes 16 20 20 20 20 - -
Diameter - L 28.6 31.8 38.1 41.3 44.5 - -
Stud bolt
Dia x Length
1"
135
1 1/4"
190
1 3/8"
220
1 1/2"
255
1 5/8"
285
-
-
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 505 533 533 546 565 - -
Diameter - D 635 710 710 745 785 - -
Thickness - B
38.1
39.7
58.8
60.4
66.7
73.1
82.6
89
101.6
108
- -
Diameter - G 533.4 533.4 533.4 533.4 533.4 - -
Diameter - K 577.9 628.6 628.6 654 685.8 - -
Height - H
67
68.6
87
88.6
98
104.4
117
123.4
152
158.4
- -
Bolt Holes 16 24 24 20 20 - -
Diameter - L 31.8 34.9 38.1 44.5 50.8 - -
Stud bolt
Dia x Length
1 1/8"
145
1 1/4"
195
1 3/8"
230
1 5/8"
275
1 7/8"
325
-
-
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 559 587 587 610 622 - -
Diameter - D 700 775 775 815 855 - -
Thickness - B
41.3
42.9
62
63.6
69.9
76.3
88.9
95.3
108
114.4
- -
Diameter - G 584.2 584.2 584.2 584.2 584.2 - -
Diameter - K 635 685.8 685.8 723.9 749.3 - -
Height - H
71
72.6
94
95.6
102
108.4
127
133.4
159
165.4
- -
Bolt Holes 20 24 24 24 20 - -
Diameter - L 31.8 34.9 41.3 44.5 54 - -
Stud bolt
Dia x Length
1 1/8"
160
1 1/4"
205
1 1/2"
240
1 5/8"
285
2"
350
-
-
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 663 702 702 718 749 - -
Diameter - D 815 915 915 940 1040 - -
Thickness - B
46.1
47.7
68.3
69.9
76.2
82.6
101.6
108
139.7
146.1
- -
Diameter - G 692.2 692.2 692.2 692.2 692.2 - -

Diameter - K 749.3 812.8 812.8 838.2 901.7 - -
Height - H
81
82.6
105
106.6
114
120.4
140
146.4
203
209.4
- -
Bolt Holes 20 24 24 24 20 - -
Diameter - L 34.9 41.3 47.6 50.8 66.7 - -
Stud bolt
Dia x Length
1 1/4"
170
1 1/2"
230
1 3/4"
265
1 7/8"
330
2 1/2"
440
-
-
-
-
DIMENSIONAL TOLERANCES OF SLIP ON FLANGES ACCORDING TO ASME B16.5
Outside Diameter
≤ 24 = 1.6 mm | > 24 = ± 3.2 mm
Inside Diameter
≤ 10 = ± 0.8 mm | ≥ 12 = + 1.6 mm / - 0 mm
Diameter of Contact Face
1.6 mm Raised Face = ± 0.8 mm
6.35 mm Raised Face, Tongue & Groove / Male-
Female = ± 0.4 mm
Outside Diameter of Hub
≤ 12 = + 2.4 mm / - 1.6 mm | ≥ 14 = ± 3.2
mm
Diameter of Counterbore
Same as for Inside Diameter
Drilling
Bolt Circle = 1.6 mm | Bolt Hole Spacing = ±
0.8 mm
Eccentricity of Bolt Circle with Respect to
Facing
≤ 2½ = 0.8 mm max. | ≥ 3 = 1.6 mm max.
Thickness
≤ 18 = + 3.2 mm / - 0 | ≥ 20 = + 4.8 mm / - 0
Length thru Hub
≤ 18 = + 3.2 mm / - 0.8 mm | ≥ 20 = + 4.8
mm / - 1.6 mm
Dimensional tolerances are in millimeters unless otherwise indicated.

Dimensions Socket Weld flanges and Stud bolts according to ASME B16.5
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 30 38 - 38 - 38 -
Diameter - D 90 95 - 95 - 120 -
Thickness - B
9.6
11.2
12.7
14.3
-
14.3
20.7
-
22.3
28.7
-
Diameter - G 35.1 35.1 - 35.1 - 35.1 -
Diameter - K 60.3 66.7 - 66.7 - 82.6 -
Height - H
14
15.6
21
22.6
-
22
28.4
-
32
38.4
-
Bolt Holes 4 4 - 4 - 4 -
Diameter - L 15.9 15.9 - 15.9 - 22.2 -
Stud bolt
Dia x Length
1/2"
55
1/2"
65
-
-
1/2"
75
-
-
3/4"
110
-
-
Nominal Pipe Size 1/2 (ID = 22.3) (F = 9.5)
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 38 48 - 48 - 44 -
Diameter - D 100 115 - 115 - 130 -
Thickness - B
11.2
12.8
14.3
15.9
-
15.9
22.3
-
25.4
31.8
-
Diameter - G 42.9 42.9 - 42.9 - 42.9 -
Diameter - K 69.9 82.6 - 82.6 - 88.9 -
Height - H
14
15.6
24
25.6
-
25
31.4
-
35
41.4
-
Bolt Holes 4 4 - 4 - 4 -
Diameter - L 15.9 19.1 - 19.1 - 22.2 -
Stud bolt
Dia x Length
1/2"
65
5/8"
75
-
-
5/8"
90
-
-
3/4"
115
-
-
Nominal Pipe Size 3/4 (ID = 27.7) (F = 11.1)

Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 49.2 54 - 54 - 52 -
Diameter - D 110 125 - 125 - 150 -
Thickness - B
12.7
14.3
15.9
17.5
-
17.5
23.9
-
28.6
35
-
Diameter - G 50.8 50.8 - 50.8 - 50.8 -
Diameter - K 79.4 88.9 - 88.9 - 101.6 -
Height - H
16
17.6
25
26.6
-
27
33.4
-
41
47.4
-
Bolt Holes 4 4 - 4 - 4 -
Diameter - L 15.9 19.1 - 19.1 - 25.4 -
Stud bolt
Dia x Length
1/2"
65
5/8"
75
-
-
5/8"
90
-
-
7/8"
125
-
-
Nominal Pipe Size 1 (ID = 34.5) (F = 12.7)
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 59 64 - 64 - 64 -
Diameter - D 115 135 - 135 - 160 -
Thickness - B
14.3
15.9
17.5
19.1
-
20.7
27.1
-
28.6
35
-
Diameter - G 63.5 63.5 - 63.5 - 63.5 -
Diameter - K 88.9 98.4 - 98.4 - 111.1 -
Height - H
19
20.6
25
26.6
-
29
35.4
-
41
47.4
-
Bolt Holes 4 4 - 4 - 4 -
Diameter - L 15.9 19.1 - 19.1 - 25.4 -
Stud bolt
Dia x Length
1/2"
70
5/8"
85
-
-
5/8"
95
-
-
7/8"
125
-
-
Nominal Pipe Size 1¼ (ID = 43.2) (F = 14.3)
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 65 70 - 70 - 70 -
Diameter - D 125 155 - 155 - 180 -
Thickness - B
15.9
17.5
19.1
20.7
-
22.3
28.7
-
31.8
38.2
-
Diameter - G 73.2 73.2 - 73.2 - 73.2 -
Diameter - K 98.4 114.3 - 114.3 - 123.8 -
Height - H
21
22.6
29
30.6
-
32
38.4
-
44
50.4
-
Bolt Holes 4 4 - 4 - 4 -
Diameter - L 15.9 22.2 - 22.2 - 28.6 -
Stud bolt
Dia x Length
1/2"
70
3/4"
90
-
-
3/4"
110
-
-
1"
140
-
-
Nominal Pipe Size 1½ (ID = 49.5) (F = 15.9)
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 78 84 - 84 - 105 -
Diameter - D 150 165 - 165 - 215 -
Thickness - B
17.5
19.1
20.7
22.3
-
25.4
31.8
-
38.1
44.5
-
Diameter - G 91.9 91.9 - 91.9 - 91.9 -
Diameter - K 120.7 127 - 127 - 165.1 -

Height - H
24
25.6
32
33.6
-
37
43.4
-
57
63.4
-
Bolt Holes 4 8 - 8 - 8 -
Diameter - L 19.1 19.1 - 19.1 - 25.4 -
Stud bolt
Dia x Length
5/8"
85
5/8"
90
-
-
5/8"
110
-
-
7/8"
145
-
-
Nominal Pipe Size 2 (ID = 62.0) (F = 17.5)
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 90 100 - 100 - 125 -
Diameter - D 180 190 - 190 - 245 -
Thickness - B
20.7
22.3
23.9
25.5
-
28.6
35
-
41.3
47.7
-
Diameter - G 104.6 104.6 - 104.6 - 104.6 -
Diameter - K 139.7 149.2 - 149.2 - 190.5 -
Height - H
27
28.6
37
38.6
-
41
47.4
-
64
70.4
-
Bolt Holes 4 8 - 8 - 8 -
Diameter - L 19.1 22.2 - 22.2 - 28.6 -
Stud bolt
Dia x Length
5/8"
90
3/4"
100
-
-
3/4"
120
-
-
1"
160
-
-
Nominal Pipe Size 2½ (ID = 74.7) (F = 19.1)
DIMENSIONAL TOLERANCES OF SOCKET WELD FLANGES ACCORDING TO ASME B16.5
Outside Diameter
≤ 24 = 1.6 mm | > 24 = ± 3.2 mm
Inside Diameter
≤ 10 = ± 0.8 mm | ≥ 12 = + 1.6 mm / - 0 mm
Female = ± 0.4 mm
≤ 12 = + 2.4 mm / - 1.6 mm | ≥ 14 = ± 3.2
mm
Drilling
0.8 mm
Facing
≤ 2½ = 0.8 mm max. | ≥ 3 = 1.6 mm max.
Thickness
≤ 18 = + 3.2 mm / - 0 | ≥ 20 = + 4.8 mm / - 0
Length thru Hub
≤ 18 = + 3.2 mm / - 0.8 mm | ≥ 20 = + 4.8
mm / - 1.6 mm

Dimensions Lap Joint flanges and Stud bolts according to ASME B16.5
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 30 38 38 38 38 38 43
Diameter - D 90 95 95 95 120 120 135
Thickness - B 11.2 14.3 14.3 14.3 22.3 22.3 30.2
Diameter - G 35.1 35.1 35.1 35.1 35.1 35.1 35.1
Diameter - K 60.3 66.7 66.7 66.7 82.6 82.6 88.9
Height - H 16 22 22 22 32 32 40
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 15.9 15.9 15.9 22.2 22.2 22.2
Stud bolt
Dia x Length
1/2"
55
1/2"
65
1/2"
75
1/2"
75
3/4"
110
3/4"
110
3/4"
120
Nominal Pipe Size 1/2 (ID = 22.9 / r = 3)
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 38 48 48 48 44 44 51
Diameter - D 100 115 115 115 130 130 140
Thickness - B 12.7 15.9 15.9 15.9 25.4 25.4 31.8
Diameter - G 42.9 42.9 42.9 42.9 42.9 42.9 42.9
Diameter - K 69.9 82.6 82.6 82.6 88.9 88.9 95.2
Height - H 16 25 25 25 35 35 43
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 19.1 19.1 19.1 22.2 22.2 22.2
Stud bolt
Dia x Length
1/2"
65
5/8"
75
5/8"
90
5/8"
90
3/4"
115
3/4"
115
3/4"
125
Nominal Pipe Size 3/4 (ID = 28.2 / r = 3)
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 49.2 54 54 54 52 52 57
Diameter - D 110 125 125 125 150 150 160
Thickness - B 14.3 17.5 17.5 17.5 28.6 28.6 35
Diameter - G 50.8 50.8 50.8 50.8 50.8 50.8 50.8
Diameter - K 79.4 88.9 88.9 88.9 101.6 101.6 108

Height - H 17 27 27 27 41 41 48
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 19.1 19.1 19.1 25.4 25.4 25.4
Stud bolt
Dia x Length
1/2"
65
5/8"
75
5/8"
90
5/8"
90
7/8"
125
7/8"
125
7/8"
140
Nominal Pipe Size 1 (ID = 35 / r = 3)
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 59 64 64 64 64 64 73
Diameter - D 115 135 125 135 160 160 185
Thickness - B 15.9 19.1 20.7 20.7 28.6 28.6 38.1
Diameter - G 63.5 63.5 63.5 63.5 63.5 63.5 63.5
Diameter - K 88.9 98.4 98.4 98.4 111.1 111.1 130.2
Height - H 21 27 29 29 41 41 52
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 19.1 19.1 19.1 25.4 25.4 28.6
Stud bolt
Dia x Length
1/2"
70
5/8"
85
5/8"
95
5/8"
95
7/8"
125
7/8"
125
1"
150
Nominal Pipe Size 1¼ (ID = 43.7 / r = 5)
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 65 70 70 70 70 70 79
Diameter - D 125 155 155 155 180 180 205
Thickness - B 17.5 20.7 22.3 22.3 31.8 31.8 44.5
Diameter - G 73.2 73.2 73.2 73.2 73.2 73.2 73.2
Diameter - K 98.4 114.3 114.3 114.3 123.8 123.8 146
Height - H 22 30 32 32 44 44 60
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 22.2 22.2 22.2 28.6 28.6 31.8
Stud bolt
Dia x Length
1/2"
70
3/4"
90
3/4"
110
3/4"
110
1"
140
1"
140
1 1/8"
170
Nominal Pipe Size 1½ (ID = 50 / r = 6)
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 78 84 84 84 105 105 95
Diameter - D 150 165 165 165 215 215 235
Thickness - B 19.1 22.3 25.4 25.4 38.1 38.1 50.9
Diameter - G 91.9 91.9 91.9 91.9 91.9 91.9 91.9
Diameter - K 120.7 127 127 127 165.1 165.1 171.4
Height - H 25 33 37 37 57 57 70
Bolt Holes 4 8 8 8 8 8 8
Diameter - L 19.1 19.1 19.1 19.1 25.4 25.4 28.6
Stud bolt
Dia x Length
5/8"
85
5/8"
90
5/8"
110
5/8"
110
7/8"
145
7/8"
145
1"
180
Nominal Pipe Size 2 (ID = 62.5 / r = 8)
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 90 100 100 100 124 125 114
Diameter - D 180 190 190 190 245 245 265
Thickness - B 22.3 25.4 28.6 28.6 41.3 41.3 57.2
Diameter - G 104.6 104.6 104.6 104.6 104.6 104.6 104.6

Diameter - K 139.7 149.2 149.2 149.2 190.5 190.5 196.8
Height - H 29 38 41 41 64 64 79
Bolt Holes 4 8 8 8 8 8 8
Diameter - L 19.1 22.2 22.2 22.2 28.6 28.6 31.8
Stud bolt
Dia x Length
5/8"
90
3/4"
100
3/4"
120
3/4"
120
1"
160
1"
160
1 1/8"
195
Nominal Pipe Size 2½ (ID = 75.4 / r = 8)
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 108 115 115 115 127 125 125
Diameter - D 190 210 210 210 240 265 305
Thickness - B 23.9 28.6 31.8 31.8 38.1 47.7 66.7
Diameter - G 127 127 127 127 127 127 127
Diameter - K 152.4 168.3 168.3 168.3 190.5 203.2 228.6
Height - H 30 43 46 46 54 73 92
Bolt Holes 4 8 8 8 8 8 8
Diameter - L 19.1 22.2 22.2 22.2 25.4 31.8 34.9
Stud bolt
Dia x Length
5/8"
90
3/4"
110
3/4"
125
3/4"
125
7/8"
145
1 1/8"
180
1 1/4"
220
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 122 135 133 133 - - -
Diameter - D 215 230 230 230 - - -
Thickness - B 23.9 30.2 35 35 - - -
Diameter - G 139.7 139.7 139.7 139.7 - - -
Diameter - K 177.8 184.2 184.2 184.2 - - -
Height - H 32 44 49 49 - - -
Bolt Holes 8 8 8 8 - - -
Diameter - L 19.1 22.2 25.4 25.4 - - -
Stud bolt
Dia x Length
5/8"
90
3/4"
110
7/8"
140
7/8"
140
-
-
-
-
-
-
Nominal Pipe Size 3½ (ID = 104.1 / r = 10)
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 135 146 146 152 160 162 165
Diameter - D 230 255 254 275 290 310 355
Thickness - B 23.9 31.8 35 38.1 44.5 54 76.2
Diameter - G 157.2 157.2 157.2 157.2 157.2 157.2 157.2
Diameter - K 190.5 200 200 215.9 235 241.3 273
Height - H 33 48 51 54 70 90 108
Bolt Holes 8 8 8 8 8 8 8
Diameter - L 19.1 22.2 25.4 25.4 31.8 34.9 41.3
Stud bolt
Dia x Length
5/8"
90
3/4"
115
7/8"
140
7/8"
145
1 1/8"
170
1 1/4"
195
1 1/2"
255
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 192 206 206 222 235 230 235
Diameter - D 280 320 320 355 380 395 485
Thickness - B 25.4 36.6 41.3 47.7 55.6 82.6 108

Diameter - G 215.9 215.9 215.9 215.9 215.9 215.9 215.9
Diameter - K 241.3 269.9 269.9 292.1 317.5 317.5 368.3
Height - H 40 52 57 67 86 119 152
Bolt Holes 8 12 12 12 12 12 8
Diameter - L 22.2 22.2 25.4 28.6 31.8 38.1 54
Stud bolt
Dia x Length
3/4"
100
3/4"
120
7/8"
150
1"
170
1 1/8"
190
1 3/8"
260
2"
345
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 246 260 260 272 298 290 305
Diameter - D 345 380 381 420 470 485 550
Thickness - B 28.6 41.3 47.7 55.6 63.5 92.1 127
Diameter - G 269.7 269.7 269.7 269.7 269.7 269.7 269.7
Diameter - K 298.5 330.2 330 349.2 393.7 393.7 438.2
Height - H 44 62 68 76 114 143 178
Bolt Holes 8 12 12 12 12 12 12
Diameter - L 22.2 22.2 28.6 31.8 38.1 44.5 54
Stud bolt
Dia x Length
3/4"
110
7/8"
140
1"
170
1 1/8"
190
1 3/8"
220
1 5/8"
290
2"
380
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 305 321 321 345 368 368 375
Diameter - D 405 445 445 510 545 585 675
Thickness - B 30.2 47.7 54 63.5 69.9 108 165.1
Diameter - G 323.9 323.9 323.9 323.9 323.9 323.9 323.9
Diameter - K 362 387.4 387.4 431.8 469.9 482.6 539.8
Height - H 49 95 102 111 127 178 229
Bolt Holes 12 16 16 16 16 12 12
Diameter - L 25.4 25.4 31.8 34.9 38.1 50.8 66.7
Stud bolt
Dia x Length
7/8"
115
1"
160
1 1/8"
190
1 1/4"
215
1 3/8"
235
1 7/8"
335
2 1/2"
490
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 365 375 375 400 420 451 441
Diameter - D 485 520 520 560 610 675 760
Thickness - B 31.8 50.8 57.2 66.7 79.4 123.9 184.2
Diameter - G 381 381 381 381 381 381 381
Diameter - K 431.8 450.8 450.8 489 533.4 571.5 619.1
Height - H 56 102 108 117 143 219 254
Bolt Holes 12 16 16 20 20 16 12
Diameter - L 25.4 28.6 34.9 34.9 38.1 54 73
Stud bolt
Dia x Length
7/8"
120
1 1/8"
170
1 1/4"
205
1 1/4"
220
1 3/8"
255
2"
375
2 3/4"
540

Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 400 425 425 432 451 495 -
Diameter - D 535 585 585 605 640 750 -
Thickness - B 35 54 60.4 69.9 85.8 133.4 -
Diameter - G 412.8 412.8 412.8 412.8 412.8 412.8 -
Diameter - K 476.3 514.4 514.4 527 558.8 635 -
Height - H 79 111 117 127 156 241 -
Bolt Holes 12 20 20 20 20 16 -
Diameter - L 28.6 31.8 34.9 38.1 41.3 60.3 -
Stud bolt
Dia x Length
1"
135
1 1/8"
180
1 1/4"
210
1 3/8"
235
1 1/2"
275
2 1/4"
405
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 457 485 485 495 508 552 -
Diameter - D 595 650 650 685 705 825 -
Thickness - B 36.6 57.2 63.5 76.2 88.9 146.1 -
Diameter - G 469.9 469.9 469.9 469.9 469.9 469.9 -
Diameter - K 539.8 571.5 571.5 603.2 616 704.8 -
Height - H 87 121 127 140 165 260 -
Bolt Holes 16 20 20 20 20 16 -
Diameter - L 28.6 31.8 38.1 41.3 44.5 66.7 -
Stud bolt
Dia x Length
1"
135
1 1/4"
190
1 3/8"
220
1 1/2"
255
1 5/8"
285
2 1/2"
445
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 505 533 533 545 565 597 -
Diameter - D 635 710 710 745 785 915 -
Thickness - B 39.7 60.4 66.7 82.6 101.6 162 -
Diameter - G 533.4 533.4 533.4 533.4 533.4 533.4 -
Diameter - K 577.9 628.6 628.6 654 685.8 774.7 -
Height - H 97 130 137 152 190 276 -
Bolt Holes 16 24 24 20 20 16 -
Diameter - L 31.8 34.9 38.1 44.5 50.8 73 -
Stud bolt
Dia x Length
1 1/8"
145
1 1/4"
195
1 3/8"
230
1 5/8"
275
1 7/8"
325
2 3/4"
495
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 560 587 587 610 622 641 -
Diameter - D 700 775 775 815 855 985 -
Thickness - B 42.9 63.5 69.9 88.9 108 177.8 -
Diameter - G 584.2 584.2 584.2 584.2 584.2 584.2 -
Diameter - K 635 685.8 685.8 723.9 749.3 831.8 -
Height - H 103 140 146 165 210 292 -
Bolt Holes 20 24 24 24 20 16 -
Diameter - L 31.8 34.9 41.3 44.5 54 79.4 -
Stud bolt
Dia x Length
1 1/8"
160
1 1/4"
205
1 1/2"
240
1 5/8"
285
2"
350
3"
540
-
-

Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 663 702 702 718 750 762 -
Diameter - D 815 915 915 940 1040 1170 -
Thickness - B 47.7 69.9 76.2 101.6 139.7 203.2 -
Diameter - G 692.2 692.2 692.2 692.2 692.2 692.2 -
Diameter - K 749.3 812.8 812.8 838.2 901.7 990.6 -
Height - H 111 152 159 184 267 330 -
Bolt Holes 20 24 24 24 20 16 -
Diameter - L 34.9 41.3 47.6 50.8 66.7 92.1 -
Stud bolt
Dia x Length
1 1/4"
170
1 1/2"
230
1 3/4"
265
1 7/8"
330
2 1/2"
440
3 1/2"
615
-
-
DIMENSIONAL TOLERANCES OF LAP JOINT FLANGES ACCORDING TO ASME B16.5
Outside Diameter
≤ 24 = 1.6 mm | > 24 = ± 3.2 mm
Inside Diameter
≤ 10 = ± 0.8 mm | ≥ 12 = + 1.6 mm / - 0 mm
Female = ± 0.4 mm
≤ 12 = + 2.4 mm / - 1.6 mm | ≥ 14 = ± 3.2
mm
Drilling
0.8 mm
Facing
≤ 2½ = 0.8 mm max. | ≥ 3 = 1.6 mm max.
Thickness
≤ 18 = + 3.2 mm / - 0 | ≥ 20 = + 4.8 mm / - 0
Length thru Hub
≤ 18 = + 3.2 mm / - 0.8 mm | ≥ 20 = + 4.8
mm / - 1.6 mm

Dimensions Threaded flanges and Stud bolts according to ASME B16.5
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 30 38 38 38 38 38 43
Diameter - D 90 95 95 95 120 120 135
Thickness - B
9.6
11.2
12.7
14.3
14.3
20.7
14.3
20.7
22.3
28.7
22.3
28.7
30.2
36.6
Diameter - G 35.1 35.1 35.1 35.1 35.1 35.1 35.1
Diameter - K 60.3 66.7 66.7 66.7 82.6 82.6 88.9
Height - H
14
15.6
21
22.6
22
28.4
22
28.4
32
38.4
32
38.4
40
46.4
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 15.9 15.9 15.9 22.2 22.2 22.2
Stud bolt
Dia x Length
1/2"
55
1/2"
65
1/2"
75
1/2"
75
3/4"
110
3/4"
110
3/4"
120
Nominal Pipe Size 1/2
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 38 48 48 48 44 44 51
Diameter - D 100 115 115 115 130 130 140
Thickness - B
11.2
12.8
14.3
15.9
15.9
22.3
15.9
22.3
25.4
31.8
25.4
31.8
31.8
38.2
Diameter - G 42.9 42.9 42.9 42.9 42.9 42.9 42.9
Diameter - K 69.9 82.6 82.6 82.6 88.9 88.9 95.2
Height - H
14
15.6
24
25.6
25
31.4
25
31.4
35
41.4
35
41.4
43
49.4
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 19.1 19.1 19.1 22.2 22.2 22.2
Stud bolt
Dia x Length
1/2"
65
5/8"
75
5/8"
90
5/8"
90
3/4"
115
3/4"
115
3/4"
125

Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 49.2 54 54 54 52 52 57
Diameter - D 110 125 125 125 150 150 160
Thickness - B
12.7
14.3
15.9
17.5
17.5
23.9
17.5
23.9
28.6
35
28.6
35
35
41.4
Diameter - G 50.8 50.8 50.8 50.8 50.8 50.8 50.8
Diameter - K 79.4 88.9 88.9 88.9 101.6 101.6 108
Height - H
16
17.6
25
26.6
27
33.4
27
33.4
41
47.4
41
47.4
48
54.4
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 19.1 19.1 19.1 25.4 25.4 25.4
Stud bolt
Dia x Length
1/2"
65
5/8"
75
5/8"
90
5/8"
90
7/8"
125
7/8"
125
7/8"
140
Nominal Pipe Size 1
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 59 64 64 64 64 64 73
Diameter - D 115 135 125 135 160 160 185
Thickness - B
14.3
15.9
17.5
19.1
20.7
27.1
20.7
27.1
28.6
35
28.6
35
38.1
44.5
Diameter - G 63.5 63.5 63.5 63.5 63.5 63.5 63.5
Diameter - K 88.9 98.4 98.4 98.4 111.1 111.1 130.2
Height - H
19
20.6
25
26.6
29
35.4
29
35.4
41
47.4
41
47.4
52
58.4
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 19.1 19.1 19.1 25.4 25.4 28.6
Stud bolt
Dia x Length
1/2"
70
5/8"
85
5/8"
95
5/8"
95
7/8"
125
7/8"
125
1"
150
Nominal Pipe Size 1¼
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 65 70 70 70 70 70 79
Diameter - D 125 155 155 155 180 180 205
Thickness - B
15.9
17.5
19.1
20.7
22.3
28.7
22.3
28.7
31.8
38.2
31.8
38.2
44.5
50.9
Diameter - G 73.2 73.2 73.2 73.2 73.2 73.2 73.2
Diameter - K 98.4 114.3 114.3 114.3 123.8 123.8 146
Height - H
21
22.6
29
31.6
32
38.4
32
38.4
44
50.4
44
50.4
60
66.4
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 22.2 22.2 22.2 28.6 28.6 31.8
Stud bolt
Dia x Length
1/2"
70
3/4"
90
3/4"
110
3/4"
110
1"
140
1"
140
1 1/8"
170
Nominal Pipe Size 1½
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 78 84 84 84 105 105 95
Diameter - D 150 165 165 165 215 215 235
Thickness - B
17.5
19.1
20.7
22.3
25.4
31.8
25.4
31.8
38.1
44.5
38.1
44.5
50.9
57.3
Diameter - G 91.9 91.9 91.9 91.9 91.9 91.9 91.9
Diameter - K 120.7 127 127 127 165.1 165.1 171.4

Height - H
24
25.6
32
33.6
37
43.4
37
43.4
57
63.4
57
63.4
70
76.4
Bolt Holes 4 8 8 8 8 8 8
Diameter - L 19.1 19.1 19.1 19.1 25.4 25.4 28.6
Stud bolt
Dia x Length
5/8"
85
5/8"
90
5/8"
110
5/8"
110
7/8"
145
7/8"
145
1"
180
Nominal Pipe Size 2
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 90 100 100 100 124 125 114
Diameter - D 180 190 190 190 245 245 265
Thickness - B
20.7
22.3
23.9
25.5
28.6
35
28.6
35
41.3
47.7
41.3
47.7
57.2
63.6
Diameter - G 104.6 104.6 104.6 104.6 104.6 104.6 104.6
Diameter - K 139.7 149.2 149.2 149.2 190.5 190.5 196.8
Height - H
27
28.6
37
38.6
41
47.4
41
47.4
64
70.4
64
70.4
79
85.4
Bolt Holes 4 8 8 8 8 8 8
Diameter - L 19.1 22.2 22.2 22.2 28.6 28.6 31.8
Stud bolt
Dia x Length
5/8"
90
3/4"
100
3/4"
120
3/4"
120
1"
160
1"
160
1 1/8"
195
DIMENSIONAL TOLERANCES OF THREADED FLANGES ACCORDING TO ASME B16.5
Outside Diameter
≤ 24 = 1.6 mm | > 24 = ± 3.2 mm
Inside Diameter
≤ 10 = ± 0.8 mm | ≥ 12 = + 1.6 mm / - 0 mm
Female = ± 0.4 mm
≤ 12 = + 2.4 mm / - 1.6 mm | ≥ 14 = ± 3.2
mm
Drilling
0.8 mm
Facing
≤ 2½ = 0.8 mm max. | ≥ 3 = 1.6 mm max.
Thickness
≤ 18 = + 3.2 mm / - 0 | ≥ 20 = + 4.8 mm / - 0
Length thru Hub
≤ 18 = + 3.2 mm / - 0.8 mm | ≥ 20 = + 4.8
mm / - 1.6 mm

Dimensions Blind flanges and Stud bolts according to ASME B16.5
Pressure Class 150 300 400 600 900 1500 2500
Diameter - D 90 95 95 95 120 120 135
Height - B
9.6
11.2
12.7
14.3
14.3
20.7
14.3
20.7
22.3
28.7
22.3
28.7
30.2
36.6
Diameter - G 35.1 35.1 35.1 35.1 35.1 35.1 35.1
Diameter - K 60.3 66.7 66.7 66.7 82.6 82.6 88.9
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 15.9 15.9 15.9 22.2 22.2 22.2
Stud bolt
Dia x Length
1/2"
55
1/2"
65
1/2"
75
1/2"
75
3/4"
110
3/4"
110
3/4"
120
Pressure Class 150 300 400 600 900 1500 2500
Diameter - D 100 115 115 115 130 130 140
Height - B
11.2
12.8
14.3
15.9
15.9
22.3
15.9
22.3
25.4
31.8
25.4
31.8
31.8
38.2
Diameter - G 42.9 42.9 42.9 42.9 42.9 42.9 42.9
Diameter - K 69.9 82.6 82.6 82.6 88.9 88.9 95
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 19.1 19.1 19.1 22.2 22.2 22.2
Stud bolt
Dia x Length
1/2"
65
5/8"
75
5/8"
90
5/8"
90
3/4"
115
3/4"
115
3/4"
125
Pressure Class 150 300 400 600 900 1500 2500
Diameter - D 110 125 125 125 150 150 160
Height - B
12.7
14.3
15.9
17.5
17.5
23.9
17.5
23.9
28.6
35
28.6
35
35
41.4
Diameter - G 50.8 50.8 50.8 50.8 50.8 50.8 50.8
Diameter - K 79.4 88.9 88.9 88.9 101.6 101.6 107.4
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 19.1 19.1 19.1 25.4 25.4 25.4
Stud bolt
Dia x Length
1/2"
65
5/8"
75
5/8"
90
5/8"
90
7/8"
125
7/8"
125
7/8"
140
Nominal Pipe Size 1

Pressure Class 150 300 400 600 900 1500 2500
Diameter - D 115 135 125 135 160 160 185
Height - B
14.3
15.9
17.5
19.1
20.7
27.1
20.7
27.1
28.6
35
28.6
35
38.1
44.5
Diameter - G 63.5 63.5 63.5 63.5 63.5 63.5 63.5
Diameter - K 88.9 98.4 98.4 98.4 111.1 111.1 130
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 19.1 19.1 19.1 25.4 25.4 28.6
Stud bolt
Dia x Length
1/2"
70
5/8"
85
5/8"
95
5/8"
95
7/8"
125
7/8"
125
1"
150
Nominal Pipe Size 1¼
Pressure Class 150 300 400 600 900 1500 2500
Diameter - D 125 155 155 155 180 180 205
Height - B
15.9
17.5
19.1
20.7
22.3
28.7
22.3
28.7
31.8
38.2
31.8
38.2
44.5
50.9
Diameter - G 73 73 73 73 73 73 73
Diameter - K 98.4 114.3 114.3 114.3 123.8 123.8 146
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 22.2 22.2 22.2 28.6 28.6 31.8
Stud bolt
Dia x Length
1/2"
70
3/4"
90
3/4"
110
3/4"
110
1"
140
1"
140
1 1/8"
170
Pressure Class 150 300 400 600 900 1500 2500
Diameter - D 150 165 165 165 215 215 235
Height - B
17.5
19.1
20.7
22.3
25.4
31.8
25.4
31.8
38.1
44.5
38.1
44.5
50.9
57.3
Diameter - G 91.9 91.9 91.9 91.9 91.9 91.9 91.9
Diameter - K 120.7 127 127 127 165.1 165.1 171.4
Bolt Holes 4 8 8 8 8 8 8
Diameter - L 19.1 19.1 19.1 19.1 25.4 25.4 28.6
Stud bolt
Dia x Length
5/8"
85
5/8"
90
5/8"
110
5/8"
110
7/8"
145
7/8"
145
1"
180
Nominal Pipe Size 2
Pressure Class 150 300 400 600 900 1500 2500
Diameter - D 180 190 190 190 245 245 265
Height - B
20.7
22.3
23.9
25.5
28.6
35
28.6
35
41.3
47.7
41.3
47.7
57.2
63.6
Diameter - G 104.6 104.6 104.6 104.6 104.6 104.6 104.6
Diameter - K 139.7 149.2 149.2 149.2 190.5 190.5 197
Bolt Holes 4 8 8 8 8 8 8
Diameter - L 19.1 22.2 22.2 22.2 28.6 28.6 31.8
Stud bolt
Dia x Length
5/8"
90
3/4"
100
3/4"
120
3/4"
120
1"
160
1"
160
1 1/8"
195

Pressure Class 150 300 400 600 900 1500 2500
Diameter - D 190 210 210 210 240 265 305
Height - B
22.3
23.9
27
28.6
31.8
38.2
31.8
38.2
38.1
44.5
47.7
54.1
66.7
73.1
Diameter - G 127 127 127 127 127 127 127
Diameter - K 152.4 168.3 168.3 168.3 190.5 205 230
Bolt Holes 4 8 8 8 8 8 8
Diameter - L 19.1 22.2 22.2 22.2 25.4 31.8 34.9
Stud bolt
Dia x Length
5/8"
90
3/4"
110
3/4"
125
3/4"
125
7/8"
145
1 1/8"
180
1 1/4"
220
Nominal Pipe Size 3
Pressure Class 150 300 400 600 900 1500 2500
Diameter - D 215 230 230 230 - - -
Height - B
22.3
23.9
28.6
30.2
35
41.4
35
41.4
- - -
Diameter - G 139.7 139.7 139.7 139.7 - - -
Diameter - K 177.8 184.2 184.2 184.2 - - -
Bolt Holes 8 8 8 8 - - -
Diameter - L 19.1 22.2 25.4 25.4 - - -
Stud bolt
Dia x Length
5/8"
90
3/4"
110
7/8"
140
7/8"
140
-
-
-
-
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - D 230 255 254 275 290 310 355
Height - B
22.3
23.9
30.2
31.8
35
41.4
38.1
44.5
44.5
50.9
54
60.4
76.2
82.6
Diameter - G 157.2 157.2 157.2 157.2 157.2 157.2 157.2
Diameter - K 190.5 200 200 215.9 235 240 273
Bolt Holes 8 8 8 8 8 8 8
Diameter - L 19.1 22.2 25.4 25.4 31.8 34.9 41.3
Stud bolt
Dia x Length
5/8"
90
3/4"
115
7/8"
140
7/8"
145
1 1/8"
170
1 1/4"
195
1 1/2"
255
Nominal Pipe Size 4
Pressure Class 150 300 400 600 900 1500 2500
Diameter - D 280 320 320 355 380 395 485
Height - B
23.9
25.5
35
36.6
41.3
47.7
47.7
54.3
55.6
62
82.6
89
108
114.4
Diameter - G 215.9 215.9 215.9 215.9 215.9 215.9 215.9
Diameter - K 241.3 269.9 269.9 292.1 317.5 320 368
Bolt Holes 8 12 12 12 12 12 8
Diameter - L 22.2 22.2 25.4 28.6 31.8 38.1 54
Stud bolt
Dia x Length
3/4"
100
3/4"
120
7/8"
150
1"
170
1 1/8"
190
1 3/8"
260
2"
345
Nominal Pipe Size 6

Pressure Class 150 300 400 600 900 1500 2500
Diameter - D 345 380 381 420 470 485 550
Height - B
27
28.6
39.7
41.3
47.7
54.1
55.6
62
63.5
69.9
92.1
98.5
127
133.4
Diameter - G 269.9 269.7 269.7 269.7 269.7 269.7 269.7
Diameter - K 298.5 330.2 330 349.2 393.7 395 438.1
Bolt Holes 8 12 12 12 12 12 12
Diameter - L 22.2 22.2 28.6 31.8 38.1 44.5 54
Stud bolt
Dia x Length
3/4"
110
7/8"
140
1"
170
1 1/8"
190
1 3/8"
220
1 5/8"
290
2"
380
Nominal Pipe Size 8
Pressure Class 150 300 400 600 900 1500 2500
Diameter - D 405 445 445 510 545 585 675
Height - B
28.6
30.2
46.1
47.7
54
60.4
63.5
69.9
69.9
76.3
108
114.4
165
171.5
Diameter - G 323.9 323.9 323.9 323.9 323.9 323.9 323.9
Diameter - K 362 387.4 387.4 431.8 469.9 485 539.7
Bolt Holes 12 16 16 16 16 12 12
Diameter - L 25.4 25.4 31.8 34.9 38.1 50.8 66.7
Stud bolt
Dia x Length
7/8"
115
1"
160
1 1/8"
190
1 1/4"
215
1 3/8"
235
1 7/8"
335
2 1/2"
490
Nominal Pipe Size 10
Pressure Class 150 300 400 600 900 1500 2500
Diameter - D 485 520 520 560 610 675 760
Height - B
30.2
31.8
49.3
50.9
57.2
63.4
66.7
73.1
79.4
85.8
123.9
130.3
184.2
190.6
Diameter - G 381 381 381 381 381 381 381
Diameter - K 431.8 450.8 450.8 489 533.4 571.5 619.1
Bolt Holes 12 16 16 20 20 16 12
Diameter - L 25.4 28.6 34.9 34.9 38.1 54 73
Stud bolt
Dia x Length
7/8"
120
1 1/8"
170
1 1/4"
205
1 1/4"
220
1 3/8"
255
2"
375
2 3/4"
540
Pressure Class 150 300 400 600 900 1500 2500
Diameter - D 535 585 585 605 640 750 -
Height - B
33.4
35
52.4
54
60.4
66.8
69.9
76.3
85.8
92.2
133.4
139.8
-
Diameter - G 412.8 412.8 412.8 412.8 412.8 412.8 -
Diameter - K 476.3 514.4 514.4 527 558.8 635 -
Bolt Holes 12 20 20 20 20 16 -
Diameter - L 28.6 31.8 34.9 38.1 41.3 60.3 -
Stud bolt
Dia x Length
1"
135
1 1/8"
180
1 1/4"
210
1 3/8"
235
1 1/2"
275
2 1/4"
405
-
-

Pressure Class 150 300 400 600 900 1500 2500
Diameter - D 595 650 650 685 705 825 -
Height - B
35
36.6
55.6
57.2
63.5
69.9
76.2
82.6
88.9
95.3
146.1
152.5
-
Diameter - G 469.9 469.9 469.9 469.9 469.9 469.9 -
Diameter - K 539.8 571.5 571.5 603.2 616 705 -
Bolt Holes 16 20 20 20 20 16 -
Diameter - L 28.6 31.8 38.1 41.3 44.5 66.7 -
Stud bolt
Dia x Length
1"
135
1 1/4"
190
1 3/8"
220
1 1/2"
255
1 5/8"
285
2 1/2"
445
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - D 635 710 710 745 785 915 -
Height - B
38.1
39.7
58.8
60.4
66.7
73.1
82.6
89
101.6
108
162
168.4
-
Diameter - G 533.4 533.4 533.4 533.4 533.4 533.4 -
Diameter - K 577.9 628.6 628.6 654 685.8 775 -
Bolt Holes 16 24 24 20 20 16 -
Diameter - L 31.8 34.9 38.1 44.5 50.8 73 -
Stud bolt
Dia x Length
1 1/8"
145
1 1/4"
195
1 3/8"
230
1 5/8"
275
1 7/8"
325
2 3/4"
495
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - D 700 775 775 815 855 985 -
Height - B
41.3
42.9
62
63.6
69.9
76.3
88.9
95.3
108
114.4
180
184.2
-
Diameter - G 584.2 584.2 584.2 584.2 584.2 584.2 -
Diameter - K 635 685.8 685.8 723.9 749.3 831.8 -
Bolt Holes 20 24 24 24 20 16 -
Diameter - L 31.8 34.9 41.3 44.5 54 79.4 -
Stud bolt
Dia x Length
1 1/8"
160
1 1/4"
205
1 1/2"
240
1 5/8"
285
2"
350
3"
540
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - D 815 915 915 940 1040 1170 -
Height - B
46.1
47.7
68.3
69.9
76.2
82.6
101.6
108
139.7
146.1
203.2
209.6
-
Diameter - G 692.2 692.2 692.2 692.2 692.2 692.2 -
Diameter - K 749.3 812.8 812.8 838.2 901.7 990.6 -
Bolt Holes 20 24 24 24 20 16 -
Diameter - L 34.9 41.3 47.6 50.8 66.7 92.1 -
Stud bolt
Dia x Length
1 1/4"
170
1 1/2"
230
1 3/4"
265
1 7/8"
330
2 1/2"
440
3 1/2"
615
-
-

Dimensions Weld Neck flanges and Stud bolts according to ASME B16.5
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 30 38 38 38 38 38 43
Diameter - D 90 95 95 95 120 120 135
Thickness - B
9.6
11.2
12.7
14.3
14.3
20.7
14.3
20.7
22.3
28.7
22.3
28.7
30.2
36.6
Diameter - G 35.1 35.1 35.1 35.1 35.1 35.1 35.1
Diameter - K 60.3 66.7 66.7 66.7 82.6 82.6 88.9
Height - H
46
47.6
51
52.6
52
58.4
52
58.4
60
66.4
60
66.4
73
79.4
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 15.9 15.9 15.9 22.2 22.2 22.2
Stud bolt
Dia x Length
1/2"
55
1/2"
65
1/2"
75
1/2"
75
3/4"
110
3/4"
110
3/4"
120
Nominal Pipe Size 1/2 - O.D. = 21.3
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 38 48 48 48 44 44 51
Diameter - D 100 115 115 115 130 130 140
Thickness - B
11.2
12.8
14.3
15.9
15.9
22.3
15.9
22.3
25.4
31.8
25.4
31.8
31.8
38.2
Diameter - G 42.9 42.9 42.9 42.9 42.9 42.9 42.9
Diameter - K 69.9 82.6 82.6 82.6 88.9 88.9 95
Height - H
51
52.6
56
57.6
57
63.4
57
63.4
70
76.4
70
76.4
79
85.4
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 19.1 19.1 19.1 22.2 22.2 22.2
Stud bolt
Dia x Length
1/2"
65
5/8"
75
5/8"
90
5/8"
90
3/4"
115
3/4"
115
3/4"
125
Nominal Pipe Size 3/4 - O.D. = 26.7
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 49.2 54 54 54 52 52 57
Diameter - D 110 125 125 125 150 150 160
Thickness - B
12.7
14.3
15.9
17.5
17.5
23.9
17.5
23.9
28.6
35
28.6
35
35
41.4
Diameter - G 50.8 50.8 50.8 50.8 50.8 50.8 50.8
Diameter - K 79.4 88.9 88.9 88.9 101.6 101.6 107.4

Height - H
54
55.6
60
61.6
62
68.4
62
68.4
73
79.4
73
79.4
89
95.4
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 19.1 19.1 19.1 25.4 25.4 25.4
Stud bolt
Dia x Length
1/2"
65
5/8"
75
5/8"
90
5/8"
90
7/8"
125
7/8"
125
7/8"
140
Nominal Pipe Size 1 - O.D. = 33.4
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 59 63.5 64 64 64 64 73
Diameter - D 115 135 135 135 160 160 185
Thickness - B
14.3
15.9
17.5
19.1
20.7
27.1
20.7
27.1
28.6
35
28.6
35
38.1
44.5
Diameter - G 63.5 63.5 63.5 63.5 63.5 63.5 63.5
Diameter - K 88.9 98.4 98.4 98.4 111.1 111.1 130
Height - H
56
57.6
64
65.6
67
73.4
67
73.4
73
79.4
73
79.4
95
101.4
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 19.1 19.1 19.1 25.4 25.4 28.6
Stud bolt
Dia x Length
1/2"
70
5/8"
85
5/8"
95
5/8"
95
7/8"
125
7/8"
125
1"
150
Nominal Pipe Size 1¼ - O.D. = 42.2
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 65 70 70 70 70 70 79
Diameter - D 125 155 155 155 180 180 205
Thickness - B
15.9
17.5
19.1
20.7
22.3
28.7
22.3
28.7
31.8
38.2
31.8
38.2
44.5
50.9
Diameter - G 73.2 73.2 73.2 73.2 73.2 73.2 73.2
Diameter - K 98.4 114.3 114.3 114.3 123.8 123.8 146
Height - H
60
61.6
67
68.6
70
76.4
70
76.4
83
89.4
83
89.4
111
117.4
Bolt Holes 4 4 4 4 4 4 4
Diameter - L 15.9 22.2 22.2 22.2 28.6 28.6 31.8
Stud bolt
Dia x Length
1/2"
70
3/4"
90
3/4"
110
3/4"
110
1"
140
1"
140
1 1/8"
170
Nominal Pipe Size 1½ - O.D. = 48.3
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 78 84 84 84 105 105 95
Diameter - D 150 165 165 165 215 215 235
Thickness - B
17.5
19.1
20.7
22.3
25.4
31.8
25.4
31.8
38.1
44.5
38.1
44.5
50.9
57.3
Diameter - G 91.9 91.9 91.9 91.9 91.9 91.9 91.9
Diameter - K 120.7 127 127 127 165.1 165.1 171.4
Height - H
62
63.6
68
69.6
73
79.4
73
79.4
102
108.4
102
108.4
127
133.4
Bolt Holes 4 8 8 8 8 8 8
Diameter - L 19.1 19.1 19.1 19.1 25.4 25.4 28.6
Stud bolt
Dia x Length
5/8"
85
5/8"
90
5/8"
110
5/8"
110
7/8"
145
7/8"
145
1"
180

Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 90 100 100 100 125 125 114
Diameter - D 180 190 190 190 245 245 265
Thickness - B
20.7
22.3
23.9
25.5
28.6
35
28.6
35
41.3
47.7
41.3
47.7
57.2
63.6
Diameter - G 104.6 104.6 104.6 104.6 104.6 104.6 104.6
Diameter - K 139.7 149.2 149.2 149.2 190.5 190.5 197
Height - H
68
69.6
75
76.6
79
85.4
79
85.4
105
111.4
105
111.4
143
149.4
Bolt Holes 4 8 8 8 8 8 8
Diameter - L 19.1 22.2 22.2 22.2 28.6 28.6 31.8
Stud bolt
Dia x Length
5/8"
90
3/4"
100
3/4"
120
3/4"
120
1"
160
1"
160
1 1/8"
195
Nominal Pipe Size 2½ - O.D. = 73
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 108 115 115 115 127 125 125
Diameter - D 190 210 210 210 240 265 305
Thickness - B
22.3
23.9
27
28.6
31.8
38.2
31.8
38.2
38.1
44.5
47.7
54.1
66.7
73.1
Diameter - G 127 127 127 127 127 127 127
Diameter - K 152.4 168.3 168.3 168.3 190.5 205 230
Height - H
68
69.6
78
79.6
83
89.4
83
89.4
102
108.4
117
123.4
168
174.4
Bolt Holes 4 8 8 8 8 8 8
Diameter - L 19.1 22.2 22.2 22.2 25.4 31.8 34.9
Stud bolt
Dia x Length
5/8"
90
3/4"
110
3/4"
125
3/4"
125
7/8"
145
1 1/8"
180
1 1/4"
220
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 122 135 133 133 - - -
Diameter - D 215 230 230 230 - - -
Thickness - B
22.3
23.9
28.6
30.2
35
41.4
35
41.4
- - -
Diameter - G 139.7 139.7 139.7 139.7 - - -
Diameter - K 177.8 184.2 184.2 184.2 - - -
Height - H
70
71.6
79
80.6
86
92.4
86
92.4
- - -
Bolt Holes 8 8 8 8 - - -
Diameter - L 19.1 22.2 25.4 25.4 - - -
Stud bolt
Dia x Length
5/8"
90
3/4"
110
7/8"
140
7/8"
140
-
-
-
-
-
-
Nominal Pipe Size 3½ - O.D. = 101.6
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 135 146 146 152 160 162 165
Diameter - D 230 255 255 275 290 310 355
Thickness - B
22.3
23.9
30.2
31.8
35
41.4
38.1
44.5
44.5
50.9
54
60.4
76.2
82.6
Diameter - G 157.2 157.2 157.2 157.2 157.2 157.2 157.2
Diameter - K 190.5 200 200 215.9 235 240 273

Height - H
75
76.6
84
85.6
89
95.4
102
108.4
114
120.4
124
130.4
190
196.4
Bolt Holes 8 8 8 8 8 8 8
Diameter - L 19.1 22.2 25.4 25.4 31.8 34.9 41.3
Stud bolt
Dia x Length
5/8"
90
3/4"
115
7/8"
140
7/8"
145
1 1/8"
170
1 1/4"
195
1 1/2"
255
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 164 180 180 189 190 197 205
Diameter - D 255 280 280 330 350 375 420
Thickness - B
22.3
23.9
33.4
35
38.1
44.5
44.5
50.9
50.8
57.2
73.1
79.5
92.1
98.5
Diameter - G 185.7 185.7 185.7 185.7 185.7 185.7 185.7
Diameter - K 215.9 235 235 266.7 279.4 290 323.8
Height - H
87
88.6
97
98.6
102
108.4
114
120.4
127
133.4
156
162.4
226
232.4
Bolt Holes 8 8 8 8 8 8 8
Diameter - L 22.2 22.2 25.4 28.6 34.9 41.3 47.6
Stud bolt
Dia x Length
3/4"
95
3/4"
120
7/8"
145
1"
165
1 1/4"
190
1 1/2"
250
1 3/4"
300
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 192 206 206 222 235 230 235
Diameter - D 280 320 320 355 380 395 485
Thickness - B
23.9
25.5
35
36.6
41.3
47.7
47.7
54.3
55.6
62
82.6
89
108
114.4
Diameter - G 215.9 215.9 215.9 215.9 215.9 215.9 215.9
Diameter - K 241.3 269.9 269.9 292.1 317.5 320 368
Height - H
87
88.6
97
98.6
103
109.4
117
123.4
140
146.4
171
177.4
273
279.4
Bolt Holes 8 12 12 12 12 12 8
Diameter - L 22.2 22.2 25.4 28.6 31.8 38.1 54
Stud bolt
Dia x Length
3/4"
100
3/4"
120
7/8"
150
1"
170
1 1/8"
190
1 3/8"
260
2"
345
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 246 260 260 272 298 290 305
Diameter - D 345 380 380 420 470 485 550
Thickness - B
27
28.6
39.7
41.3
47.7
54.1
55.6
62
63.5
69.9
92.1
98.5
127
133.4
Diameter - G 269.7 269.7 269.7 269.7 269.7 269.7 269.7
Diameter - K 298.5 330.2 330 349.2 393.7 395 438.1
Height - H
100
101.6
110
111.6
117
123.4
133
139.4
162
168.4
213
219.4
318
324.4
Bolt Holes 8 12 12 12 12 12 12
Diameter - L 22.2 22.2 28.6 31.8 38.1 44.5 54
Stud bolt
Dia x Length
3/4"
110
7/8"
140
1"
170
1 1/8"
190
1 3/8"
220
1 5/8"
290
2"
380
Nominal Pipe Size 8 - O.D. = 219

Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 305 321 321 345 368 368 375
Diameter - D 405 445 445 510 545 585 675
Thickness - B
28.6
30.2
46.1
47.7
54
60.4
63.5
69.9
69.9
76.3
108
114.4
165
171.5
Diameter - G 323.9 323.9 323.9 323.9 323.9 323.9 323.9
Diameter - K 362 387.4 387.4 431.8 469.9 485 539.7
Height - H
100
101.6
116
117.6
124
130.4
152
158.4
184
190.4
254
260.4
419
425.4
Bolt Holes 12 16 16 16 16 12 12
Diameter - L 25.4 25.4 31.8 34.9 38.1 50.8 66.7
Stud bolt
Dia x Length
7/8"
115
1"
160
1 1/8"
190
1 1/4"
215
1 3/8"
235
1 7/8"
335
2 1/2"
490
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 365 375 375 400 420 451 441
Diameter - D 485 520 520 560 610 675 760
Thickness - B
30.2
31.8
49.3
50.9
57.2
63.4
66.7
73.1
79.4
85.8
123.9
130.3
184.2
190.6
Diameter - G 381 381 381 381 381 381 381
Diameter - K 431.8 450.8 450.8 489 533.4 571.5 619.1
Height - H
113
114.6
129
130.6
137
143.4
156
162.4
200
206.4
283
289.4
464
470.4
Bolt Holes 12 16 16 20 20 16 12
Diameter - L 25.4 28.6 34.9 34.9 38.1 54 73
Stud bolt
Dia x Length
7/8"
120
1 1/8"
170
1 1/4"
205
1 1/4"
220
1 3/8"
255
2"
375
2 3/4"
540
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 400 425 425 432 451 495 -
Diameter - D 535 585 585 605 640 750 -
Thickness - B
33.4
35
52.4
54
60.4
66.8
69.9
76.3
85.8
92.2
133.4
139.8
-
Diameter - G 412.8 412.8 412.8 412.8 412.8 412.8 -
Diameter - K 476.3 514.4 514.4 527 558.8 635 -
Height - H
125
126.6
141
142.6
149
155.4
165
171.4
212
219.4
298
304.4
-
Bolt Holes 12 20 20 20 20 16 -
Diameter - L 28.6 31.8 34.9 38.1 41.3 60.3 -
Stud bolt
Dia x Length
1"
135
1 1/8"
180
1 1/4"
210
1 3/8"
235
1 1/2"
275
2 1/4"
405
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 457 485 485 495 508 550 -
Diameter - D 595 650 650 685 705 825 -
Thickness - B
35
36.6
55.6
57.2
63.5
69.9
76.2
82.6
88.9
95.3
146.1
152.5
-
Diameter - G 469.9 469.9 469.9 469.9 469.9 469.9 -
Diameter - K 539.8 571.5 571.5 603.2 616 705 -

Height - H
125
126.6
144
145.6
152
158.4
178
184.4
216
222.4
311
317.4
-
Bolt Holes 16 20 20 20 20 16 -
Diameter - L 28.6 31.8 38.1 41.3 44.5 66.7 -
Stud bolt
Dia x Length
1"
135
1 1/4"
190
1 3/8"
220
1 1/2"
255
1 5/8"
285
2 1/2"
445
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 505 533 533 545 565 597 -
Diameter - D 635 710 710 745 785 915 -
Thickness - B
38.1
39.7
58.8
60.4
66.7
73.1
82.6
89
101.6
108
162
168.4
-
Diameter - G 533.4 533.4 533.4 533.4 533.4 533.4 -
Diameter - K 577.9 628.6 628.6 654 685.8 775 -
Height - H
138
139.6
157
158.6
165
171.4
184
190.4
229
235.4
327
333.4
-
Bolt Holes 16 24 24 20 20 16 -
Diameter - L 31.8 34.9 38.1 44.5 50.8 73 -
Stud bolt
Dia x Length
1 1/8"
145
1 1/4"
195
1 3/8"
230
1 5/8"
275
1 7/8"
325
2 3/4"
495
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 560 587 587 610 622 640 -
Diameter - D 700 775 775 815 855 985 -
Thickness - B
41.3
42.9
62
63.6
69.9
76.3
88.9
95.3
108
114.4
180
184.2
-
Diameter - G 584.2 584.2 584.2 584.2 584.2 584.2 -
Diameter - K 635 685.8 685.8 723.9 749.3 831.8 -
Height - H
143
144.6
160
161.6
168
174.4
190
196.4
248
254.4
356
362.4
-
Bolt Holes 20 24 24 24 20 16 -
Diameter - L 31.8 34.9 41.3 44.5 54 79.4 -
Stud bolt
Dia x Length
1 1/8"
160
1 1/4"
205
1 1/2"
240
1 5/8"
285
2"
350
3"
540
-
-
Pressure Class 150 300 400 600 900 1500 2500
Diameter - A 663 702 702 718 750 762 -
Diameter - D 815 915 915 940 1040 1170 -
Thickness - B
46.1
47.7
68.3
69.9
76.2
82.6
101.6
108
139.7
146.1
203.2
209.6
-
Diameter - G 692.2 692.2 692.2 692.2 692.2 692.2 -
Diameter - K 749.3 812.8 812.8 838.2 901.7 990.6 -
Height - H
151
152.6
167
168.6
175
181.4
203
209.4
292
298.4
406
412.4
-
Bolt Holes 20 24 24 24 20 16 -
Diameter - L 34.9 41.3 47.6 50.8 66.7 92.1 -
Stud bolt
Dia x Length
1 1/4"
170
1 1/2"
230
1 3/4"
265
1 7/8"
330
2 1/2"
440
3 1/2"
615
-
-

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