Design, Application & Installation of Custom Clamps - March

Editor's Notes

• #2: Display this slide before the presentation begins, while viewers are joining…. Do not say what is on slide…. Switch to next slide before welcoming
• #3: Hello everyone, I would like to welcome you to our Webinar on Customized Pipe Clamps. The Webinar today is hosted by Piping Technology & Products. I am Jerry Godina and I will be your presenter. If you would like to join in on the audio portion of the presentation, please make sure you select speakers/headphones in the audio choice box and double check that your volume is turned up. You can also listen to us by telephone, 9:00 am for the United States, just dial: (1) 516-453-0014, for countries other than the US, please refer to the list of numbers in your confirmation e-mail. The access code for this presentation is 215-892-458 2:00 pm for the United States, just dial: (1) 323-417-4600, for countries other than the US, please refer to the list of numbers in your confirmation e-mail. The access code for this presentation is 305-051-978 Also, if you have a question during the presentation, please feel free to type a question into the text box you see to the right of the presentation, or if you prefer, you can ask questions after the presentation during our “Questions and Answers Session.”
• #4: For those of you who are unfamiliar with us, I want to quickly go over some background information. If you would like to know more, please visit our “About Us” section at www.pipingtech.com. Our parent company, Piping Technology & Products, Inc., also known as PT&P, has been… in business since 1975, PT&P and its wholly owned subsidiaries, US Bellows, Sweco Fab, Pipe Shields, and Anchor Darling, offer a wide range of engineered products and services for various industries and applications. Our product line is extensive… from engineered pipe supports, expansion joints, pre-insulated pipe supports, and miscellaneous fabrication to various engineering and technical services, PT&P has decades of experience providing products and services for all your engineering and construction needs.
• #5: This photo shows an aerial view of our headquarters here in Houston, Texas Our facility is located on a 35 acre property including additional room for future expansion We are just miles away from the Port of Houston which allows us to quickly and conveniently ship to a variety of countries throughout the world
• #6: I would like to welcome those, who are just joining in. If you have any questions, we have a panel of experts standing by to answer by chat. Suspension of Horizontal Line Suspension of Vertical Line Restraint of Horizontal Line Restraint of Vertical Line
• #7: SECTION 1: Suspension of Horizontal Line Schematic of a Pipeline Suspended Horizontally
• #8: Suspension of Horizontal Line: Standard Loads & Temperatures, Minimal Insulation Explain “Standard Design” vs. “Custom Design” for the purposes of this presentation Custom: 1. FRP piping, Ductile Iron Piping, Plastic Piping, etc. where the diameter differs from a standard pipe. 2. High temperature application or a different type of material (could be one in the same) maybe using stainless steel for high temperature where you do not want a cross contamination b/w carbon steel and stainless steel. 3. If load exceed standard clamp maximum loading capabilities. fig. 50 light 2-bolt pipe clamp fig. 60 heavy 2-bolt pipe clamps The standard (off-the-self) clamps which are manufactured on a daily basis. For us, a suspension of an un-insulated line can most readily be accomplished with the use of our standard 2-bolt pipe clamp. These are made of carbon steel with either an unfinished or a galvanized finish and they are usually used to support lines which have no insulation. Pipe sizes range from ½ " to 36 " with a maximum load rating for our standard figure 50 model clamp being 4,000 lb. on a 36 " clamp. In suspension of other pipes, we have figure 60, our heavy duty pipe clamp, which has a larger load rating, but the same configuration. But it is utilized for 3 " to 36 " lines with a maximum load rating of 28,000 lb. Once again these can be procured in either a unfinished condition where the client would specify a finish of painting or some other material or a hot-dipped galvanized finish.
• #9: Suspension of Horizontal Line (Standard Loads & Temperatures, Minimal Insulation) fig. 83 Adjustable Clevis Hanger Clevis type beam clamp assemblies. Standard product but can be manufactured to any special designs required. Use of beam type of clamp and a clevis type of clamp to suspend insulated lines wherein the insulation did not need to interfere with the clamp hanger assembly. This support assembly is designed to support a pipe that is 10 " in diameter and used to suspend loads of 3,600 lb. Nice ability of these clamps is that in conjunction with the beam clamp, we can have a swing which exceeds the standard 4 degrees recommended by MSS Standards. Original Notes Below The rod measures 7/8 " in diameter. The function of the beam clamp assembly is to support the pipe and allow it to swing. The clamp requires no welding which allows for a quick and easy installation. Carbon steel with a hot-dipped galvanized finish.
• #10: Suspension of Horizontal Line (Standard Loads & Temperatures, but with Insulation) fig. 70 Light 3-Bolt Pipe Clamp fig. 80 Heavy 3-Bolt Pipe Clamp When there is insulation involved, we want to use a 3-bolt clamp so the load bolt can be outside the insulation. These are also standard clamps made within our facility which have standard stock sizes, standard bolt sizes and can be made from standard material. Figure 70 which is our light-duty 3-bolt clamp which covers pipe sizes from ½ " to 36 " with a maximum load rating for the 36 " in the neighborhood of 10,500 lb. We also carry heavy duty 3-bolt clamps which is our standard figure 80 and is utilized for pipe sizes 1 ½ " to 36 " and a maximum load rating on a 36 " clamp of 28,000 lb. Similar to figure 50 2-bolt clamp, the figure 70 3-bolt clamp comes in a unfinished or a hot-dipped galvanized condition.
• #11: Suspension of Horizontal Line: Standard Loads & Temperatures, but with Insulation fig. 89 Clevis Hanger for Insulated Lines C-Type Constant Assembly http://www.pipingtech.com/news/arc_pw_2002/engps2002_07.htm File name of image: c-type_horizconstant
• #12: Suspension of Horizontal Line: Standard Loads & High Temperatures, but with Insulation fig. 70a Alloy Light 3-Bolt Pipe Clamp Picture: Stainless Steel Finish
• #13: Suspension of Horizontal Line: Standard Temperatures & High Loads, with Insulation Carbon Steel 3-Bolt Pipe Clamp Clamp Calculator Load: 20,000 lb. Pipe Size: 20" Operating Temp: 650°F When the design parameters exceed the standard…. (COMBO) For Figure 80, max load is 15,300 lb. and stock size is 1 " x 5 " and bolt is 2 " diameter http://www.pipingtech.com/news/arc_pw_2005/sacs2005_02.htm
• #14: Suspension of Horizontal Line: High Loads & Temperatures, with Insulation Top: Constant Spring and Clamp Assemblies Rod & Clamp Material: ASTM A240, Grade 304 Stainless Steel http://www.pipingtech.com/news/arc_pw_2003/engps2003_15.htm Bottom: Constant Spring and 3-Bolt Clamp Assemblies Clamp Material: ASTM A240, Grade 304 Stainless Steel Pipe Size Range: 4 " to 8 " http://www.pipingtech.com/news/arc_pw_2003/engps2003_13.htm
• #15: Suspension of Horizontal Line: Finite Element Analysis of Pipe Clamp FEA helps us to optimize materials, bolting and types of manufacture that we are using to optimize weight considerations and cost considerations. Here we are looking at two 24 " pipes with significantly different loads (Right: 33,500 lb. load and Left: 68,200 lb. load). Both will be used in high temperature service on grade 91 pipe, however because the loads are so different, it is more beneficial to use two different clamps (Right: with a load of 33,500 lb. we reduced the stock size to 1 ¼ " by 8 " ) (Left: because the load is 68,200 lb. the minimum stock size would be 2 " by 12 " ). FEA helped to optimize the clamps on an individual basis. Even though both clamps have the same pipe size and operating temperatures, the load constraint was the greatest factor determining the clamp and load bolt size. Original Notes Below FEA on Figure 80 heavy duty 3-bolt pipe clamp for a high temperature application. Due to the high temperature, the clamps are fabricated from alloy steel, A387 Grade 91. We analyzed two different pipes – one for a 68,200 lb. load and the other for a 33,500 lb. load. Conclusion: After the analyses, we found that the bending radius of forming the ears is 1.5 times the plate thickness. The AISC recommends that the values are 3 times the thickness of the plates of 1 to 1 ½ " thickness and 4 times the thickness for greater thicknesses. The FEA analyses demonstrate that larger radiuses would result in lower stresses. This conclusion has led to significantly lower costs to our customers by justifying the use of less steel.
• #16: Suspension of Horizontal Line: High Loads & Temperatures and Insulation Top: Custom 3-Bolt Pipe Clamps (1,065 ° F and load range 8,000 lb. to 25,000 lb.) Bottom: 66" 3-Bolt Pipe Clamp (500 ° F and operating load of 24,000 lb.) Original Notes Below Top picture here shows our figure 70A three-bolt pipe clamps custom designed for a power plant in Florida. 14-18 " clamps wherein the loads exceeded the maximum load rating of our standard clamps, we were looking to accomplish load ratings between 8,000 and 25,000 lb. where the standard maximum load rating is in the neighborhood of 4,000 lb. We needed to modify the clamp stock size either in thickness or width or both, as well as the bolt size which is necessary to hold up the specified load. This project included 30 clamps fabricated from SA 387 grade 22 alloy steel. These clamps are designed to suspend pipe lines where there is high temperature and great thermal movement. ( http://www.pipingtech.com/news/arc_pw_2004/sacs2004_08.htm) The bottom picture is a custom designed three-bolt pipe clamp made for 66 " duct work (for a chemical company). By using a FEA program, the clamp was designed for an suspension load of 24,000 lb 500°F. After formation, the clamps’ dimensions measured 97.75 " overall length and 69.5 " at its widest point. This clamp will be used in conjunction with a spring hanger and a rod to support the pipe line. ( http://www.pipingtech.com/news/arc_pw_2002/sacs2002_01.htm)
• #17: Suspension of Horizontal Line: High Loads & Temperatures and Insulation Figure 42 Yoke U-Bolt Size Range: 8 ⅝" – ¼" Load Range: 9,500 lb. – 18,500 lb. Figure 43 Yoke U-Bolt (Heavy Duty) Size Range: 8 ⅝" – 36" Load Range: 13,500 lb. – 27,000 lb. Materials: Yoke, Load Bolt and Load Distribution Strap is Chrome Molybdenum Steel. U-Bolt is Stainless Steel. Maximum Temperature: 1100°F
• #18: Suspension of Horizontal Line (High Loads-70,000 lb., High Temperatures-exceeds 1050 ° F, Large Diameter-42 " and Insulation) 42 " Heavy Duty Alloy Yoke Clamp Now we will look at how we utilize Finite Element Analysis to help in the design of clamps. Here you see a special 42 " heavy duty alloy yoke clamp which was designed for a load excess of 70,000 lb. The Finite Element Analysis was first conducted to optimize the design and it showed making the yoke out of 6 " thick plate actually produced more loading inside the u-bolt than in the yolk section. The u-bolt was made out of a 3 " diameter bar and the yolk was made out of 6” fabricated chrome-molly steel. This was a high temperature application wherein the operating temperature exceeded 1,050 °F, and as a result, the clamp was made out of chrome-molly 387 grade 22. http://www.pipingtech.com/news/arc_pw_2001/sacs2001_02.htm
• #19: Suspension of Horizontal Line: Finite Element Analysis of Yoke Clamp Where complicated design configurations exist… Piping Technology & Products, Inc. has extensive in-house finite element analysis capabilities using ProEngineer, ANSYS, and a variety of other software packages. FEA software is used to simulate the loads and resulting stresses which a particular design might experience in the field. These time and money-saving computer simulations are used to select designs for prototypes. We later use these prototypes to test products with actual loads to confirm our design loads and safety features. FEA provides very realistic and accurate analysis of mechanical parts that undergo specified thermal and mechanical loads. Performing and FEA is time-effective and a cost-effective complement to physical testing -- following a preliminary finite analysis with a physical load test significantly reduces the design cycle time. Interpreting and understanding FEA's proves useful to explaining stress and strain conditions to customers in a highly visual manner. The use of FEA significantly improves PT&P's engineering, research, and design capabilities. (http://www.pipingtech.com/tour/cad.htm) - Conceptual design developed - FEA performed to 1.) confirm design capabilities and 2.) Optimize overall design regarding Materials/Fab. Processes
• #20: Suspension of Horizontal Line: High Loads & Temperatures and Insulation 24 Custom Pipe Support Assemblies (E-Type Constant Spring Support and Cradle Assembly) Constants designed for loads of 9,856 lb. to 13,288 lb. and total travel ranges from 3.5" to 5.5". The cradle assemblies are to support pipes with operational temperatures of 1070 °F to 1100 °F . The pipe saddle was made by splitting a section of A387-11 chrome alloy pipe. 304 stainless steel eye rod (1-3/4"), two u-bolts (27" inside diameter), and two 33" lengths of 3" diameter SCH. 80 pipe. http://www.pipingtech.com/news/arc_pw_2001/engps2001_04.htm
• #21: I would like to welcome those, who are just joining in. If you have any questions, we have a panel of experts standing by to answer by chat. SECTION 2: Suspension of Vertical Line Schematic of a Pipeline Suspended Vertically
• #22: Suspension of Vertical Line fig. 90 Riser Clamp Materials: Carbon Steel Finish: Unfinished or Galvanized Maximum Temperature: 650°F Figure 90 Riser Clamp Size Range: ½" – 24" Load Range: 225 lb. – 3,200 lb.
• #23: Suspension of Vertical Line: Variable Spring and Riser Clamp Assemblies The variable springs have welded components as opposed to bolted components found in our standard assembly. Material: Carbon steel and instead of galvanizing, the assemblies were coated with a red-oxide primer due to high temperature operating conditions of the furnace (this prevents the possibility of molten zinc from the galvanizing process contaminating the furnace tubes) Load Range: 143 lb. to 660 lb. Total travel range: 3/4" to 2" http://www.pipingtech.com/news/arc_pw_2003/engps2003_11.htm
• #24: Suspension of Vertical Line Top: Variable Spring and Riser Clamp Assemblies Operating Load: 6600 lb. Pipe size: 18", total travel: 2" Clamps fabricated from A 387 Grade 22 alloy steel (variable springs are carbon steel) http://www.pipingtech.com/news/arc_pw_2004/engps2004_08.htm (W:\\digital_camera\\2004\\Feb\\b&v_beaumont_pipeclamps73985) Bottom: Carbon Steel Riser Clamp Length: 86", Height: 12", Width: 1-3/4" Pipe Size: 30", Weight: 1200 lb. Operating Load: 22,400 lb. at 650 °F W:\\digital_camera\\2007\\02 Feb\\clamp 89255
• #25: Suspension of Vertical Line: Type-3 Riser Clamp This riser clamp is designed for a power plant and has a support capacity of 80,000 lb. They will be used on a 16 " pipe with 2 " flanges for added support Riser clamps are generally used for support and steadying of steel pipe risers either insulated or bare, cast iron pipe, or conduit. http://www.pipingtech.com/news/arc_pw_2007/sacs2007_01.htm
• #26: Suspension of Vertical Line: Type-3 Riser Clamps “Extended distance between load bolt and pipe centerline” Figure 190 Type 3 Riser Clamps The clamps are designed for 17 " and 24 " pipes and have an overall length of 71 " and 87 " respectively Utilizing gusset plates at the clamp’s bend radius allowed for the smallest, yet sufficient clamp stock size for the specified loads The smaller clamp has an operating capacity of 14,000 lb. while the larger clamp operates at 20,500 lb. Chrome-Moly 387 Grade 22 bar stock was used with A193 Grade B7 bolting to accommodate high temperature operating conditions. http://www.pipingtech.com/news/arc_pw_2003/sacs2003_02.htm
• #27: I would like to welcome those, who are just joining in. If you have any questions, we have a panel of experts standing by to answer by chat. SECTION 3: Restraint of Horizontal Line Schematic of a Pipeline Restrained Horizontally
• #28: Restraint of Horizontal Line Anchor (3-way restraint) Standard Hold-Down (HD-1)
• #29: Restraint of Horizontal Line Anchor (3-way restraint) Top: Standard Hold-Down (HD-1) Used on pipelines where little or no insulation is required Pipe Size: 2" Material: SA36 carbon steel Temperature: 750F http://www.pipingtech.com/news/arc_pw_2002/sacs2002_06.htm Bottom: Long Tangent U-Bolts Material: carbon steel Pipe size range: 8" to 16" Load: 9900 lb. Temperature: 650 ° F http://www.pipingtech.com/news/arc_pw_2005/longubolts2005.htm W:\\digital_camera\\2004\\Feb\\b&v_beaumont_pipeclamps73985
• #30: Restraint of Horizontal Line: Guide (2-way restraint) Hold-Down (HD-2) These are HD-2 hold down clamps that will be used to fit a 16 " pipe at an oil refinery in Michigan This particular design is generally used on pipelines where there is a high temperature and great thermal movement requirements The hold downs allow for axial movement while restraining lateral movement The clamp and base plate are fabricated from carbon steel with PTFE, 25% glass filled, material bonded to the radius and plate http://www.pipingtech.com/news/arc_pw_2004/sacs2004_05.htm
• #31: Restraint of Horizontal Line: Guide (2-way restraint) Hold-Down (HD-2) Custom: Large Diameter, Wedge Supports This particular design is fabricated with a wedge support for a forty-two inch (42 " ) pipe The hold down includes a PTFE, 25% glass filled lining and will be used to control and reduce pipe vibration at an LNG plant The hold down and wedge support are fabricated from A26 carbon steel and a fabric pad which is exceptionally suited for vibration impact and declination http://www.pipingtech.com/news/arc_pw_2003/sacs2003_03.htm
• #32: Restraint of Horizontal Line: Guide (2-way restraint) Top: Pipe Clamp Assemblies 40 clamp attachments for a petrochemical plant in Texas. The clamp attachments shown are used for supporting vertical pipe sections to vessel clip anchors. These braces are designed for a maximum horizontal moment of 15,000 ft-lb at the vessel clip. All the clamps provided were made of carbon steel with a hot-dip-galvanized finish. The assembly lengths were fabricated per specifications provided by the client. The clamp components were designed and fabricated for non-standard pipe diameters (i.e. 13-3/4", 16-1/2") so that they could be used on insulated or finned pipelines. (http://www.pipingtech.com/news/arc_pw_2002/sacs2002_04.htm) Bottom: Cylinder Pipe Guides cylinder pipe guides (aka spider guides) for pipes ranging from 1 " to 20 " in diameter with 1 " to 4 " of insulation. These guides are designed to control lateral pipe movement and maintain the alignment of the piping through its axial and contraction cycles. A single piping run uses multiple spider guides to avoid a fulcrum or an imposed lateral deflection on critical components. (http://www.pipingtech.com/news/arc_pw_2003/fabshoes2003_05.htm)
• #33: Suspension of Horizontal Line: High Loads & Temperatures and Insulation Custom 3-Bolt Pipe Clamp What makes a clamp a custom design, we see a clamp which is utilized for a 24 " outside diameter pipe. Stock size is large for this clamp being 9 " stock material. Different stock size than normal, different dimension from the center of the clamp to the load bolt. There are over 450 products, just like this one, featured in our Product of the Week Archives… located at pipingtech.com, in the “News” section. Original Notes Below This is a custom-designed 3-bolt clamp for a 765 MW natural gas-fired combined cycle facility. These clamps in conjunction with variable springs, will allow for vertical and axial pipe movement while restricting lateral movements. Based on design considerations, the clamp "E" dimension, from pipe centerline to outer load bolt, is 25 " . The clamps were designed for operation at 1,065°F and per customer-supplied information. The vertical design load is 1,848 lb. and the maximum lateral load is 19,207 lb. The clamp plates are made of A387 GR. 22 plate material. The stanchion pieces are made of A335 GR.22 pipe and the side stop plates are made of carbon steel. http://www.pipingtech.com/news/arc_pw_2002/sacs2002_03.htm
• #34: Restraint of Horizontal Line FEA of Pipe Clamp FEA helps to optimize the materials and helps to review what the clamp is doing to the pipe itself. In this case, the pipe was plastic and did not have great residual stresses induced by the clamp. In an effort to reduce that, we designed a clamp wherein the 2 center sections actually met instead of having a gap b/w them wherein field personnel or construction personnel might have to over torque the clamp to get them to come together. This clamp was designed with a zero gap such that when the clamp was tightened, the stress would be known at the pipe intersection. In this instance we were trying to overcome some axial force on the pipe but at the same time barely overcome that axial force such that an 8,000 lb. axial load would not induce anymore residual stresses longitudinally inside the pipe. Original Notes Below A stress analysis was conducted of an 8" plastic pipe constrained in the axial direction by a special pipe clamp. PT&P’s final design assumes that three clamps in a series will resist a total expected axial force of 8,000 lb. Since the area of the pipe in contact with the support affects the overall stress distribution, it is necessary to determine how much contact there is at different pressures via FEA in two steps. CONCLUSION: The maximum stress on the clamp is determined to be twenty-eight thousand PSI (28,000 PSI). Stresses in the figure on the right would normally be of little concern in mild steel at typical operating temperatures. If it were a problem, extending the gussets upwards is recommended. In addition, it is recommended to increase pipe length if higher stress is desired. This is due to increased contact between the pipe and clamp, which spreads stress over more area allowing for greater pressures.
• #35: Restraint of Horizontal Line Pipe Shoe with Clamps Pipe Shoe Job# 106067 W:\\digital_camera\\2009\\September\\Pipe Clamps 106067
• #36: I would like to welcome those, who are just joining in. If you have any questions, we have a panel of experts standing by to answer by chat. SECTION 4: Restraint of Vertical Line Schematic of a Pipeline Restrained Vertically
• #37: Restraint of Vertical Line Guide (2 degrees of freedom) 3-bolt clamp (Teton) Sway Brace Application Restraining Steam line in Vertical Temperatures High restraint load, not a lifting vertical load Changing orientation, design conditions do not change, still able to use same design, just flip 90 degrees
• #38: Restraint of Vertical Line Guide (2 degrees of freedom) Used in conjunction with a yoke clamp Allows movement in axial and translational directions
• #39: Restraint of Vertical Line Guide (2 degrees of freedom) 10 Sway Braces were designed and manufactured for a Petroleum Company in Louisiana… The total travel distance is 14 "; t he standard PT&P braces have springs that allow 3" of total travel distance. These sway braces were custom designed to provide a total travel distance of 5" and 14". The center-to-center dimensions range from 92 ¼" to 115" with internal supports to prevent buckling. The desired spring rates for the sway braces is 450 lb./in. and 1,350 lb./in. The custom sway brace assemblies are comprised of pipes (for spring housing), springs (sizes dependent on spring rate and total travel) and in some cases, ball joints.
• #40: Restraint of Vertical Line Guide (1 degree of freedom) Riser Clamps, 54 " in diameter, custom designed to be installed in the Emission Control unit of a 1600 MW coal fired power plant in Texas The clamps include neoprene lining adhesively bonded to the carbon steel to protect the FRP pipe Prior to assembly, the clamps received a coat of red alkyd primer to prevent rust and resist moisture and corrosion The power plant is fired with lignite coal, and will be 75% cleaner than conventional power plants. W:\\Productoftheweek\\PW2009\\09292009 - potw + v18 rem W:\\digital_camera\\2009\\June\\TXU Riser Clamps 96983
• #41: Restraint of Vertical Line Anchor (3-way restraint) Pipe hangers designed for an on-going project to rebuild the San Francisco-Oakland Bay Bridge Fabricated from carbon steel and galvanized to withstand corrosion from the ocean waters and rough winds They will be welded to anchor plates which are set in a cast concrete to the bottom cavity of the bridge These particular supports utilize friction holding devices known as MegaLug ®, which permit attachment to the pipes without welding The main design function of these supports is to include improvements in regards to strength and durability to withstand high loads during earthquakes and other seismic events. Designed for 6 " , 10 " and 12 " ductile iron pipe They are hot dip galvanized to protect against corrosion, and will be used in conjunction with hydraulic snubbers The snubbers aid in protecting against axial shock loading as well as providing vertical weight support
• #42: I would like to welcome those, who are just joining in. If you have any questions, we have a panel of experts standing by to answer by chat. SECTION 5: Special Conditions Special Conditions: Example 1 3 Fold Problem: 1.) We had a 97" duct work which is much greater than our standard clamp can withstand and 2.) interference problems in that the duct work had very close tolerances with the structure below it and 3.) the duct work was thin walled and any stresses induced on the duct by the clamp can be detrimental. In an effort to alleviate all 3 of those conditions, a 3-piece pipe clamp was made with a bottom cradle section, approx. 150 degrees and 2 upper load restraining sections which were used to suspend the load. The bottom section was made wider to distribute the load over the duct work at 18" wide while the upper sections were 12" wide. These clamps were designed to withstand a maximum loading of approx. 17,000 lb. and also to allow the duct work to receive as little residual stresses from the clamping structure as possible. This was a 3 pronged attack with eliminated the lower bolts on the bottom which allowed the clamp to be as close to the bottom section of the duct work as possible. Original Notes Below This is a custom design 3-piece pipe clamp used to support 97" diameter stainless steel duct work. The duct work is being added to a refinery for an expansion project in Ponco City, Oklahoma. Each section of the clamp assembly is formed from a continuous plate and gussets are added at each of the bolt locations for increased strength and rigidity. Due to the ducts having a relatively thin wall, these clamps are designed wider than necessary in an effort to reduce localized stresses on the duct work. The lower section of each clamp is formed to create a 150° cradle. This acts as a cradle by supporting the duct without inducing extra pressure, which might cause the duct wall to buckle or bend. The upper sections are formed from 1/2" thick by 12" wide bar stock, whereas the lower sections are formed from a 1/2" thick by 18" wide. All three sections are rolled to an inner radius of 48 1/2" and the welded gusset plates are all 1/2" thick. The upper sections are formed at 105° each, and the upper load bolt is 2" in diameter while the 6 clamping bolts are 1 1/2" in diameter. The maximum load to be carried by these pipe clamps is 16,888 lb. Each pipe clamp will be used in conjunction with a variable spring support to accommodate movements as high as 2 1/4".
• #43: Special Conditions: Example 2 Slightly different type of clamping configuration This is a custom clamp that will be used in conjunction with a hydraulic snubber to restrain the pipe movement during extremely high disturbances. (snubber utilized when a upset is found in the system) Snubber needed when a 68,000 lb. upset load occurred within the system. 2 lower links joined together by an upper yoke assembly. The distance between the links is used to accommodate the pipe size, which in this instance was a 4" pipe with a 4 ½" diameter. As a result the lower links can be slipped over the pipe and then slid down the pipe until they came to a connection where 2 flanges with the approximate diameter of 10" were used. This allowed us to use not only the strongest portion of the pipe for suspension, but also allowed us to not induce a great deal of stress on the 4" section of pipe. In this instance the 68,000 lb. load would be held at two flange connections instead of being induced onto the pipe. In an effort to sustain that load, you can see the top load bolt is 2 ¼" in diameter cause at the time of this disturbance upset loading, this would be taking the entire load induced onto the snubber. Original Notes Below The outer diameter of the clamp section is 16", and the inner diameter is 10" The yoke, lugs, and strap sections of the clamp are carbon steel, and the clamp bolts and load bolt/pin are stainless steel. The upper lugs are fabricated from 3/4" thick plate
• #44: Special Conditions: Example 3 These custom riser clamp assemblies are designed with neoprene lining and will be used on an oil rig in the Gulf of Mexico They are fabricated from carbon steel and will support vertical pipe lines Each assembly consists of two clamps and a clamp stand Several coats of marine paint finish were applied to prevent corrosion due to salt water content and open air exposure
• #45: Our engineering and design department is involved in the following processes: -Piping, Pipe Support and Structural Design -3D Modeling Technology -Pipe Stress Analysis, in which we use Caesar II -For Structural Analysis, we use STAAD II -Our engineering and design department uses Finite Element Analysis for many projects: -FEA is used for Special Stress and/or Thermal Problems -It is used in 3D Part Design -They use ANSYS for Mesh Generation and Analysis and Results Analysis -Our Engineering and Design department is also involved in Field Testing.
• #46: PT&P offers on-site installation guidance, inspection and/or maintenance of pipe supports and snubber inspection. We carry a system of stock standard items and have an “on-call” engineering team available 24x7.
• #50: Since we don’t have much time this evening, you may want to check out our website; there you will find a plethora of technical information, including different Tests we carry out, FEA Analysis, and much more.
• #51: That concludes our Webinar on Customized Pipe Clamps…. I hope everyone enjoyed the presentation and as a reminder, we have a staff of experts for each product category standing by to answer any questions you may have. You can just chat them now while in session until the end of the hour, you can also send them to us by e-mail at info@pipingtech.com, or you can visit our discussion forum and post your question there, just click on the blue graphic labeled “DISCUSSION FORUM” on the left hand side of our home page at www.pipingtech.com