Introduction to Pumps.pdf
- 1. Engineering for the Petroleum and Process Industries MECHANICAL ENGINEERING DEPARTMENT INTRODUCTION TO
- 2. WHAT ARE PUMPS? Pumps are machines that are used to increase the total energy level of liquid stream
- 3. CENTRIFUGAL PUMPS PUMPS ARE USED FOR Moving large volumes of liquid from/to storage tanks or into pipeline Moving process fluid and circulating cooling water Providing water for fire fighting…etc.
- 4. TYPES OF PUMPS POSITIVE DISPLACEMENT DYNAMIC RECIPROCATING ROTARY CENTRIFUGAL MIXED FLOW AXIAL FLOW PLUNGER PISTON DIAPHRAGM VANE GEAR LOBE SCREW PISTON
- 5. Products Storage Area Main Process Area
- 7. CENTRIFUGAL PUMPS OPERATING PRINCIPAL The two main components of a centrifugal pump are the impeller and the volute. The impeller produces liquid velocity and the volute forces the liquid to discharge from the pump converting velocity to pressure.
- 8. CENTRIFUGAL PUMPS EXTERNAL COMPONENTS EXTERNAL COMPONENTS OF PUMP FLIXABLE COUPLING
- 9. CENTRIFUGAL PUMPS INTERNAL COMPONENTS Discharge nozzle Suction nozzle Impeller Bearing Shaft Volute Seal
- 10. CENTRIFUGAL PUMPS INTERNAL COMPONENTS CONT’D Different Types Of Impellers OPEN IMPELLER SEMI-OPEN IMPELLER CLOSED IMPELLER
- 11. CENTRIFUGAL PUMPS INTERNAL COMPONENTS CONT’D Leakage along pump shaft cane be minimized by Packing and Mechanical Seal. Packing is used to minimize leakage along the shaft by filling the stuffing box but it can’t prevent leakage by 100%. Packing on shaft sleeve Lantern ring
- 12. Mechanical Seal is used when NO leakage is required specially in hazard cases mechanical seal shall be used. Cross section view of mechanical seal Seat Rotating face O ring Grub screw Peg CENTRIFUGAL PUMPS INTERNAL COMPONENTS CONT’D
- 13. CENTRIFUGAL PUMPS BEARING LUBRICATION Proper Bearing lubrication is important to prevent overheat, rust and corrosion OIL RING LUBRICATION CONSTANT LEVEL OILER
- 14. Heat generation is a problem in centrifugal pump particularly in pumps moving high temperature fluids, excessive heat is most damaging at bearing locations, water jackets are used here. CENTRIFUGAL PUMPS STUFFING BOX & BEARING HOUSING COOLING Heat exchanger
- 15. CENTRIFUGAL PUMPS PERFORMANCE CURVES
- 16. Vapor Pressure Pressure Vapor pressure is the pressure required to keep a liquid in the liquid state. VAPOR PRESSURE, CAPITATION & NPSH Cavitation occurs when a fluid's operational pressure drops below it's vapor pressure causing gas pockets and bubbles to form and collapse.
- 17. NPSH stands for Net Positive Suction Head, and reflects the energy left in a fluid when the fluid is captured by the impeller and flung out to the casing. There are two expressions for NPSH: NPSHAvailable and NPSHRequired NPSHAvailable is a function of the system in which the pump operates. NPSHRequired is a function of the pump design. NPSHavail = hs - hvpa + hst - hfs
- 18. CENTRIFUGAL PUMPS CLASSIFICATION Centrifugal pumps can be classified according to:- Shaft Position Bearing Position Type of Impeller Number of Impellers Volute Design Fluid Flow
- 19. CENTRIFUGAL PUMPS CLASSIFICATION CONT’D Vertical pumps Horizontal pump Vertical in-line pump Vertical turbine pump Sump pump Shaft Position
- 20. CENTRIFUGAL PUMPS CLASSIFICATION CONT’D Between bearing pump Overhung pump Bearing Position
- 21. CENTRIFUGAL PUMPS CLASSIFICATION CONT’D Type Of Impeller
- 22. Multi stage pump Single stage pump CENTRIFUGAL PUMPS CLASSIFICATION CONT’D Number Of Impellers
- 24. CENTRIFUGAL PUMPS CLASSIFICATION CONT’D Fluid Flow Axial Flow Pump Radial Flow
- 29. Positive displacement pumps are used for:- POSITIVE DISPLACEMENT PUMPS Low volume applications. High pressures are required to move fluids.
- 30. POSITIVE DISPLACEMENT PUMPS OPERATING PRINCIPAL A positive displacement pump has an expanding cavity on the suction side of the pump and a decreasing cavity on the discharge side. Liquid is allowed to flow into the pump as the cavity on the suction side expands and the liquid is forced out of the discharge as the cavity collapses.
- 31. RECIPROCATING PUMPS Reciprocating pumps types are :- Piston Pumps Plunger Pumps Diaphragm Pumps Diaphragm pump Piston pump
- 32. Plunger pump Safety relief valve Pulsation dampener Chemical injection pumps
- 33. Internal gear pumps External gear pump External gear pump - Fluid is carried between gear teeth and is expelled by the meshing of the gears which cooperate to provide continuous sealing between the pump inlet and outlet. Internal gear pump - The outer gear (rotor) drives the inner or idler gear on a stationary pin. The gears create voids as they come out of mesh and liquid flows into the cavities. As the gears come back into mesh, the volume is reduced and the liquid is forced. Rotary Pumps
- 34. Screw pump Archimedes Screw Progressive cavity pump Screw pumps Screw pumps carry fluid in the spaces between the screw threads. The fluid is displaced axially as the screws mesh. Single screw pumps - are commonly called progressive cavity pumps. They have a rotor with external threads and a stator with internal threads. The rotor threads are eccentric to the axis of rotation. Multiple screw pumps - have multiple external screw threads. These pumps may be timed or un-timed
- 35. Axial piston pump Lobe pump Radial piston pump Lobe pumps Fluid is carried between rotor lobes which cooperate to provide continuous sealing between the pump inlet and outlet. Piston pumps Axial piston pump - depends on beveled “wobble” plate or equivalent off-center linkage system to reciprocating pistons. Radial piston pump – depends on eccentric stator (or rotor) to give reciprocating action.