pumps ennpi course

Engineering for the Petroleum and Process Industries

MECHANICAL ENGINEERING DEPARTMENTMECHANICAL ENGINEERING DEPARTMENT

INTRODUCTION TOINTRODUCTION TO

WHAT ARE PUMPS?WHAT ARE PUMPS?

Pumps are machines that are used to increase the total energy level Pumps are machines that are used to increase the total energy level of liquid streamof liquid stream

CENTRIFUGAL PUMPSCENTRIFUGAL PUMPS

PUMPS ARE USED FORPUMPS ARE USED FOR

Moving large volumes of liquid from/to storage Moving large volumes of liquid from/to storage tanks or into pipelinetanks or into pipeline

Moving process fluid and circulating cooling waterMoving process fluid and circulating cooling water

Providing water for fire fighting…etc. Providing water for fire fighting…etc.

TYPES OF PUMPSTYPES OF PUMPS

POSITIVE DISPLACEMENTPOSITIVE DISPLACEMENT DYNAMICDYNAMIC

RECIPROCATINGRECIPROCATING ROTARYROTARY CENTRIFUGALCENTRIFUGAL MIXED FLOWMIXED FLOW AXIAL FLOWAXIAL FLOW

PLUNGERPLUNGER

PISTONPISTON

DIAPHRAGMDIAPHRAGM

VANEVANE

GEARGEAR

LOBELOBE

SCREWSCREW

PISTONPISTON

Products Storage AreaProducts Storage Area

Main Process AreaMain Process Area

CENTRIFUGALCENTRIFUGAL PUMPSPUMPS

CENTRIFUGAL PUMPS OPERATING PRINCIPAL CENTRIFUGAL PUMPS OPERATING PRINCIPAL

The two main components of a The two main components of a centrifugal pump are the centrifugal pump are the impellerimpeller and and the the volutevolute. .

The impeller produces liquid velocity The impeller produces liquid velocity and the volute forces the liquid to and the volute forces the liquid to discharge from the pump converting discharge from the pump converting velocity to pressure. velocity to pressure.

CENTRIFUGAL PUMPS EXTERNAL COMPONENTS CENTRIFUGAL PUMPS EXTERNAL COMPONENTS

EXTERNAL COMPONENTS OF EXTERNAL COMPONENTS OF PUMP PUMP

FLIXABLE COUPLING FLIXABLE COUPLING

CENTRIFUGAL PUMPS INTERNAL COMPONENTS CENTRIFUGAL PUMPS INTERNAL COMPONENTS

Discharge nozzle Discharge nozzle

Suction nozzle Suction nozzle

Impeller Impeller

Bearing Bearing

Shaft Shaft

Volute Volute

Seal Seal

CENTRIFUGAL PUMPS INTERNAL COMPONENTSCENTRIFUGAL PUMPS INTERNAL COMPONENTSCONT’D CONT’D

Different Types Of ImpellersDifferent Types Of Impellers

OPEN IMPELLEROPEN IMPELLER

SEMI-OPEN IMPELLERSEMI-OPEN IMPELLER

CLOSED IMPELLERCLOSED IMPELLER

CENTRIFUGAL PUMPS INTERNAL COMPONENTSCENTRIFUGAL PUMPS INTERNAL COMPONENTSCONT’D CONT’D

Leakage along pump shaft cane be Leakage along pump shaft cane be minimized by minimized by PackingPacking and and Mechanical SealMechanical Seal. .

PackingPacking is used to minimize leakage along is used to minimize leakage along the shaft by filling the stuffing box but it the shaft by filling the stuffing box but it can’t prevent leakage by 100%.can’t prevent leakage by 100%.

Packing on shaft sleevePacking on shaft sleeve

Lantern ringLantern ring

Mechanical SealMechanical Seal is used when NO is used when NO leakage is required specially in hazard leakage is required specially in hazard cases mechanical seal shall be used.cases mechanical seal shall be used.

Cross section view of mechanical seal Cross section view of mechanical seal

Seat Seat Rotating Rotating face face

O ring O ring Grub Grub

screw screw

Peg Peg

CENTRIFUGAL PUMPS INTERNAL CENTRIFUGAL PUMPS INTERNAL COMPONENTS CONT’DCOMPONENTS CONT’D

CENTRIFUGAL PUMPS BEARING LUBRICATION CENTRIFUGAL PUMPS BEARING LUBRICATION

Proper Proper Bearing lubricationBearing lubrication is is important to prevent overheat, rust and important to prevent overheat, rust and corrosioncorrosion

OIL RING LUBRICATION OIL RING LUBRICATION

CONSTANT LEVEL OILER CONSTANT LEVEL OILER

Heat generation is a problem in Heat generation is a problem in centrifugal pump particularly in centrifugal pump particularly in pumps moving high temperature pumps moving high temperature fluids, excessive heat is most fluids, excessive heat is most damaging at bearing locations, damaging at bearing locations, water jackets are used here.water jackets are used here.

CENTRIFUGAL PUMPS STUFFING BOX & BEARING HOUSING CENTRIFUGAL PUMPS STUFFING BOX & BEARING HOUSING COOLINGCOOLING

Heat exchangerHeat exchanger

CENTRIFUGAL PUMPS PERFORMANCE CURVESCENTRIFUGAL PUMPS PERFORMANCE CURVES

Vapor Pressure Vapor Pressure

Pressure Pressure

Vapor pressureVapor pressure is the pressure required to keep is the pressure required to keep a liquid in the liquid state.a liquid in the liquid state.

VAPOR PRESSURE, CAPITATION & NPSHVAPOR PRESSURE, CAPITATION & NPSH

CavitationCavitation occurs when a fluid's operational occurs when a fluid's operational pressure drops below it's vapor pressure pressure drops below it's vapor pressure causing gas pockets and bubbles to form and causing gas pockets and bubbles to form and collapse. collapse.

NPSHNPSH stands for stands for NNet et PPositive ositive SSuction uction HHead, and reflects the energy ead, and reflects the energy left in a fluid when the fluid is captured by the impeller and flung out to left in a fluid when the fluid is captured by the impeller and flung out to the casing. There are two expressions for NPSH: NPSHthe casing. There are two expressions for NPSH: NPSHAvailableAvailable and and

NPSHNPSHRequiredRequired

NPSHNPSHAvailableAvailable is a function of the system in which the pump operates. is a function of the system in which the pump operates.

NPSHNPSHRequiredRequired is a function of the pump design. is a function of the pump design.

NPSHNPSHavailavail = hs - h = hs - hvpavpa + h + hstst - h - hfsfs

CENTRIFUGAL PUMPS CLASSIFICATIONCENTRIFUGAL PUMPS CLASSIFICATION

Centrifugal pumps can be classified according to:-Centrifugal pumps can be classified according to:-

Shaft PositionShaft PositionShaft PositionShaft Position

Bearing Bearing PositionPositionBearing Bearing PositionPosition

Type of Type of ImpellerImpellerType of Type of ImpellerImpeller

Number of Number of ImpellersImpellers

Number of Number of ImpellersImpellers

Volute Volute DesignDesignVolute Volute DesignDesign

Fluid Fluid FlowFlowFluid Fluid FlowFlow

CENTRIFUGAL PUMPS CLASSIFICATIONCENTRIFUGAL PUMPS CLASSIFICATIONCONT’DCONT’D

Vertical pumpsVertical pumps

Horizontal pump Horizontal pump Vertical in-line pump Vertical in-line pump Vertical turbine pump Vertical turbine pump Sump pump Sump pump

Shaft PositionShaft Position


Between bearing pump Between bearing pump

Overhung pump Overhung pump

Bearing PositionBearing Position


Type Of ImpellerType Of Impeller

Multi stage pump Multi stage pump Single stage pump Single stage pump


Number Of ImpellersNumber Of Impellers


Volute DesignVolute Design


Fluid FlowFluid Flow

Axial Flow PumpAxial Flow Pump

Radial Flow Radial Flow

UNITED GAS DERIVATIVESUGD

POSITIVE DISPLACEMENT PUMPSPOSITIVE DISPLACEMENT PUMPS

Positive displacement pumpsPositive displacement pumps are used for:- are used for:-

POSITIVE DISPLACEMENT PUMPSPOSITIVE DISPLACEMENT PUMPS

Low volume applications.Low volume applications.

High pressures are required to move fluids.High pressures are required to move fluids.

POSITIVE DISPLACEMENT PUMPS OPERATING PRINCIPAL POSITIVE DISPLACEMENT PUMPS OPERATING PRINCIPAL

A positive displacement pump has an A positive displacement pump has an expanding cavity on the suction side of the expanding cavity on the suction side of the pump and a decreasing cavity on the pump and a decreasing cavity on the discharge side. discharge side.

Liquid is allowed to flow into the pump as the Liquid is allowed to flow into the pump as the cavity on the suction side expands and the cavity on the suction side expands and the liquid is forced out of the discharge as the liquid is forced out of the discharge as the cavity collapses. cavity collapses.

RECIPROCATING PUMPSRECIPROCATING PUMPS

Reciprocating pumpsReciprocating pumps types are :- types are :-

Piston PumpsPiston Pumps

Plunger PumpsPlunger Pumps

Diaphragm PumpsDiaphragm Pumps

Diaphragm pumpDiaphragm pump Piston pumpPiston pump

Plunger pumpPlunger pump

Safety relief valve Safety relief valve

Pulsation dampener Pulsation dampener

Chemical injection pumpsChemical injection pumps

Internal gear pumpsInternal gear pumps

External gear pumpExternal gear pump

External gear pumpExternal gear pump - - Fluid is carried Fluid is carried between gear teeth and is expelled by the between gear teeth and is expelled by the meshing of the gears which cooperate to meshing of the gears which cooperate to provide continuous sealing between the pump provide continuous sealing between the pump inlet and outlet.inlet and outlet.

Internal gear pumpInternal gear pump - - The outer gear The outer gear (rotor) drives the inner or idler gear on a (rotor) drives the inner or idler gear on a stationary pin. The gears create voids as they stationary pin. The gears create voids as they come out of mesh and liquid flows into the come out of mesh and liquid flows into the cavities. As the gears come back into mesh, cavities. As the gears come back into mesh, the volume is reduced and the liquid is forced. the volume is reduced and the liquid is forced.

Rotary PumpsRotary Pumps

Screw pumpScrew pump

Archimedes Screw Archimedes Screw

Progressive cavity pumpProgressive cavity pump

Screw pumpsScrew pumps

Screw pumps carry fluid in the spaces Screw pumps carry fluid in the spaces between the screw threads. The fluid is between the screw threads. The fluid is displaced axially as the screws mesh. displaced axially as the screws mesh.

Single screw pumps - are commonly called Single screw pumps - are commonly called progressive cavity pumps. They have a rotor progressive cavity pumps. They have a rotor with external threads and a stator with with external threads and a stator with internal threads. The rotor threads are internal threads. The rotor threads are eccentric to the axis of rotation. eccentric to the axis of rotation.

Multiple screw pumps - have multiple Multiple screw pumps - have multiple external screw threads. These pumps may external screw threads. These pumps may be timed or un-timed be timed or un-timed

Axial piston pumpAxial piston pump

Lobe pumpLobe pump

Radial piston pumpRadial piston pump

Lobe pumpsLobe pumps

Fluid is carried between rotor lobes which Fluid is carried between rotor lobes which cooperate to provide continuous sealing cooperate to provide continuous sealing between the pump inlet and outlet. between the pump inlet and outlet.

Piston pumpsPiston pumpsAxial piston pump - depends on Axial piston pump - depends on beveled “wobble” plate or equivalent beveled “wobble” plate or equivalent off-center linkage system to off-center linkage system to reciprocating pistons.reciprocating pistons.

Radial piston pump – depends on Radial piston pump – depends on eccentric stator (or rotor) to give eccentric stator (or rotor) to give reciprocating action.reciprocating action.