Positive displacement pumpsPositive displacement pumpsPUMPS

DISPLACMENT DYNAMIC

RECIPROCATING ROTARY

DIAPGRAGM

PISTON, PLUNGER

GEAR

SCREW

VANE

LIQUID RING

ECCENTRIC

LOBE

STEAM-DOUBLE ACTING

POWER

CIRCUMFERENTIAL

PERISTALTIC

CharacteristicsCharacteristics

pulse with each strokepulse with each stroke self-priming self-priming pressure increases internal leakage pressure increases internal leakage

Positive displacement versus centrifugal Positive displacement versus centrifugal pumpspumps

Pressure Pressure dependencedependence

• Viscosity effectViscosity effect EfficiencyEfficiency

Rotary pumpsRotary pumps A Rotary pump is a positive displacement pump A Rotary pump is a positive displacement pump

consisting of a chamber containing gears, cams, screws, consisting of a chamber containing gears, cams, screws, vanes, plungers or similar elements actuated by relative vanes, plungers or similar elements actuated by relative rotation of the drive shaft & casing rotation of the drive shaft & casing

CharacteristicsCharacteristics::

1.1. time continuous liquid seal is maintained between the time continuous liquid seal is maintained between the inlet & the outlet ports inlet & the outlet ports

2.2. amount of liquid displaced by each revolution is amount of liquid displaced by each revolution is independent of speedindependent of speed

3.3. smooth and uniform Flow smooth and uniform Flow

Pumping action of rotary pumpsPumping action of rotary pumps::

Closed-to-outlet-open-to-inlet

Closed-to-outlet-closed-to-inlet

Open-to-outlet-Closed-to-inlet

For a good pumping actionFor a good pumping action::

The open to inlet (OTI) volume The open to inlet (OTI) volume should grow smoothly & should grow smoothly & continuously with pump rotation.continuously with pump rotation.

The closed to inlet & outlet (CTIO) The closed to inlet & outlet (CTIO) volume should remain constant with volume should remain constant with pump rotation.pump rotation.

The open to outlet (OTO) volume The open to outlet (OTO) volume should shrink smoothly & should shrink smoothly & continuously with pump rotation.continuously with pump rotation.

ECCENTRIC PUMPSECCENTRIC PUMPS

How the pump worksHow the pump works

BenefitsBenefits Operates with dry suction. Operates with dry suction. Simple to install. Simple to install. High suction lift. High suction lift. Constant capacity at varying heads. Constant capacity at varying heads. Single cover access. Single cover access. Simple to operate. Simple to operate. Remove the last drop from Remove the last drop from

containers. containers.

ApplicationsApplications Bilge pumpsBilge pumps Sludge pumpsSludge pumps Fuel oil pumpsFuel oil pumps Ballast pumpsBallast pumps Pressure systemsPressure systems Purification pumpsPurification pumps Low magnetic pumps (mine sweeper)Low magnetic pumps (mine sweeper) Black water pumps Black water pumps

Vane PumpsVane Pumps

Internal vane pumpsInternal vane pumps

Flexible vane pumpFlexible vane pump

Vane pump Advantages Vane pump Advantages Medium capacity Medium capacity Medium speed Medium speed Thin liquids Thin liquids Sometimes preferred for solvents, LPG Sometimes preferred for solvents, LPG Can run dry for short periods Can run dry for short periods Develops good vacuum Develops good vacuum

Vane pump DisadvantagesVane pump Disadvantages Can have two stuffing boxes Can have two stuffing boxes Complex housing Complex housing Not suitable for high pressures Not suitable for high pressures Not suitable for high viscosity Not suitable for high viscosity

Vane pump Applications Vane pump Applications Auto Industry - Fuels, Lubes, Auto Industry - Fuels, Lubes,

Refrigeration Coolants Refrigeration Coolants Barge Unloading Barge Unloading Bulk Transfer of LPG and NH3 Bulk Transfer of LPG and NH3 Chemical Process Industry Chemical Process Industry Ethanol/Alcohol Refining Ethanol/Alcohol Refining Fertilizer Production - CO Transfer Fertilizer Production - CO Transfer Lubrication Blending - Solvents, Oils Lubrication Blending - Solvents, Oils Power Generation - Fuels, Lubrication Power Generation - Fuels, Lubrication

Materials of ConstructionMaterials of Construction

Externals (head, casing, bracket)Externals (head, casing, bracket) - Cast iron, ductile iron, steel, and - Cast iron, ductile iron, steel, and stainless steel. stainless steel.

Vane, PushrodsVane, Pushrods - Viton®, Ryton®, - Viton®, Ryton®, PPS, carbon, Teflon®, and peek. PPS, carbon, Teflon®, and peek.

Liquid Ring PumpLiquid Ring Pump

componentscomponents

How the pump worksHow the pump works

BenefitsBenefits Simplified ConstructionSimplified Construction

All components are designed for 24 hour per day All components are designed for 24 hour per day continuous service under the most demanding industrial continuous service under the most demanding industrial conditions. conditions.

Environmentally CleanEnvironmentally CleanNo oil used for lubrication or sealing. No oil vapor No oil used for lubrication or sealing. No oil vapor discharged to the atmosphere. discharged to the atmosphere.

High Vacuum CharacteristicsHigh Vacuum CharacteristicsExclusive axial flow design permits efficient operation in the Exclusive axial flow design permits efficient operation in the full vacuum range from 0 to 29 inches of mercury (760-25 full vacuum range from 0 to 29 inches of mercury (760-25 Torr). Torr).

Advanced DesignAdvanced DesignEmploys mechanical seal and O-ring gaskets for zero Employs mechanical seal and O-ring gaskets for zero leakage. leakage.

Vibrationless OperationVibrationless OperationNo special foundations required. No special foundations required.

Constant PowerConstant PowerPower requirements are constant over the full vacuum Power requirements are constant over the full vacuum range. Non-overloading. range. Non-overloading.

Low MaintenanceLow MaintenanceNo metal-to-metal contact between rotating and stationary No metal-to-metal contact between rotating and stationary elements.elements.

Advantages:Advantages: Tolerate entrained liquids and solidsTolerate entrained liquids and solids Isothermal compression (for monomer Isothermal compression (for monomer

recovery, explosive gases)recovery, explosive gases) OilfreeOilfree Very safe for explosive gasesVery safe for explosive gases Simple design for corrosion resistant Simple design for corrosion resistant

materialsmaterialsDisadvantages:Disadvantages: High power absorbedHigh power absorbed Process fluid and auxiliary fluid are mixed-Process fluid and auxiliary fluid are mixed-

up / contaminatedup / contaminated

Peristaltic pumpPeristaltic pump

How the pump workHow the pump work

Peristaltic pump advantages:Peristaltic pump advantages: Hydraulically operated Hydraulically operated speed variationsspeed variations to meet all job to meet all job

demands.demands. Enables pumping of heavy, fibered, thick, and abrasive Enables pumping of heavy, fibered, thick, and abrasive

materials at high volumes.materials at high volumes. The pump's mechanical maintenance is limited to The pump's mechanical maintenance is limited to hose hose

wearwear.. Pumped material Pumped material does not come in contactdoes not come in contact with any with any

moving parts.moving parts. Dry runningDry running can occur without causing damage to the can occur without causing damage to the

pump.pump. Replacement of hoseReplacement of hose is quick and easy. is quick and easy. Pumping is Pumping is cleanlinesscleanliness

ApplicationsApplications Peristaltic pumps are used mostly in Peristaltic pumps are used mostly in chemical chemical

laboratorieslaboratories, but they can be used for injection of , but they can be used for injection of chemicals into small irrigation systems. chemicals into small irrigation systems.

Peristaltic pumps have a variety of Peristaltic pumps have a variety of medical applicationsmedical applications. . They can be used to add They can be used to add nutrients to bloodnutrients to blood, to force , to force blood through filters to clean it, or to move blood through blood through filters to clean it, or to move blood through the body and lungs during the body and lungs during open heart surgery open heart surgery

Gear PumpGear Pump

transfer liquids both of high and low viscosity transfer liquids both of high and low viscosity are used in the lubrication circulation systems of are used in the lubrication circulation systems of

various shipboard installations various shipboard installations uniform delivery, simple manufacture, uniform delivery, simple manufacture,

comparatively high capacity for their small overall comparatively high capacity for their small overall size size

convenient installation in comparison with other convenient installation in comparison with other types of pumps types of pumps

consist of a driver and a driven consist of a driver and a driven gear enclosed in a casing and in gear enclosed in a casing and in

mesh with each other mesh with each other

The gears may be of either the spur, The gears may be of either the spur, helical or spiral typehelical or spiral type

Gear pump can be classified into two Gear pump can be classified into two types:types:

(1) Internal Gear Pump(1) Internal Gear Pump

(2) External Gear Pump(2) External Gear Pump

(1) Internal Gear Pump(1) Internal Gear Pump

1. Overview1. Overview well-suited for a wide range of viscosity applications well-suited for a wide range of viscosity applications

because of their relatively low speedsbecause of their relatively low speeds superior high-viscosity handling capabilitiessuperior high-viscosity handling capabilities smooth, nonpulsating flowsmooth, nonpulsating flow self-priming and can run dryself-priming and can run dry only two moving partsonly two moving parts

22 . .How it worksHow it works

33 . .Advantages & DisadvantagesAdvantages & Disadvantages

AdvantagesAdvantages• Only two moving partsOnly two moving parts• nonpulsating discharge nonpulsating discharge • Ideal for high-viscosity Ideal for high-viscosity

liquidsliquids• Constant and even Constant and even

dischargedischarge

DisadvantagesDisadvantages • requires moderate requires moderate

speeds speeds • Medium pressure Medium pressure

limitations limitations • One bearing runs in the One bearing runs in the

product pumped product pumped • Overhung load on shaft Overhung load on shaft

bearing bearing

• Reversible pumpReversible pump• Low NPSH required Low NPSH required • Easy to maintain Easy to maintain • Flexible design offers Flexible design offers

application application customization customization

44 . .Materials of ConstructionMaterials of Construction

• Externals (head, casing, bracket)Externals (head, casing, bracket) - Cast iron, - Cast iron, ductile iron, steel, stainless steel, Alloy 20, and higher ductile iron, steel, stainless steel, Alloy 20, and higher alloys. alloys.

• Internals (rotor, idler)Internals (rotor, idler) - Cast iron, ductile iron, steel, - Cast iron, ductile iron, steel, stainless steel, Alloy 20, and higher alloys. stainless steel, Alloy 20, and higher alloys.

• BushingBushing - Carbon graphite, bronze, silicon carbide, - Carbon graphite, bronze, silicon carbide, tungsten carbide, ceramic, colomony, and other tungsten carbide, ceramic, colomony, and other specials materials as needed. specials materials as needed.

• Shaft SealShaft Seal - Lip seals, component mechanical seals, - Lip seals, component mechanical seals, industry-standard cartridge mechanical seals, gas industry-standard cartridge mechanical seals, gas barrier seals, magnetically-driven pumps. barrier seals, magnetically-driven pumps.

• PackingPacking - Impregnated packing, if seal not required. - Impregnated packing, if seal not required.

55 . .ApplicationsApplications

• Barge, tanker, and terminal loading and Barge, tanker, and terminal loading and unloading. unloading.

• Circulating. Circulating. • Transferring. Transferring. • Lubricating. Lubricating. • Booster. Booster.

• General industrial. General industrial. • Marine applications. Marine applications. • Petrochemical. Petrochemical.

((22 ) )External Gear PumpExternal Gear Pump

1. Overview1. Overview found in lubrication pumps in machine toolsfound in lubrication pumps in machine tools External gear pumps handle viscous liquidsExternal gear pumps handle viscous liquids Reduced speeds with high-viscosity liquids results in Reduced speeds with high-viscosity liquids results in

greater efficiencygreater efficiency popular for precise transfer applicationspopular for precise transfer applications

22 . .How it worksHow it works

33 . .Advantages & DisadvantagesAdvantages & Disadvantages

AdvantagesAdvantages• High speed. High speed. • Medium pressure. Medium pressure. • No overhung bearing No overhung bearing

loads. loads. • Relatively quiet Relatively quiet

operation.operation. • Design accommodates Design accommodates

wide variety of wide variety of materials.materials.

DisadvantagesDisadvantages• Four bushings in Four bushings in

liquid area. liquid area. • No solids allowed. No solids allowed. • Fixed End Clearances.Fixed End Clearances.

44 . .Materials of ConstructionMaterials of Construction

• Externals (head, casing, bracket)Externals (head, casing, bracket) - Iron, - Iron, ductile iron, steel, stainless steel. ductile iron, steel, stainless steel.

• Internals (rotor, idler)Internals (rotor, idler) - Steel, stainless steel. - Steel, stainless steel. • BushingBushing - Carbon, bronze, silicon carbide. - Carbon, bronze, silicon carbide. • Shaft SealShaft Seal - Packing, lip seal, component - Packing, lip seal, component

mechanical seal, and magnetically-driven mechanical seal, and magnetically-driven pump. pump.

55 . .ApplicationsApplications

• Industrial and mobile applications Industrial and mobile applications • Fuel and lubrication Fuel and lubrication • Metering Metering • Hydraulic applications Hydraulic applications • Precise metering applications Precise metering applications • Low-volume transfers Low-volume transfers • Light or medium duty Light or medium duty

Lobe PumpLobe Pump

1. Overview1. Overview are used in a variety of industriesare used in a variety of industries high efficiency , reliability, corrosion resistance, and high efficiency , reliability, corrosion resistance, and

good clean-in-place and service-in-place good clean-in-place and service-in-place can handle solids (e.g., cherries and olives), and a can handle solids (e.g., cherries and olives), and a

variety of liquids variety of liquids output is constant and continuous output is constant and continuous require very little maintenance require very little maintenance

22 . .How it worksHow it works

33 . .Advantages & DisadvantagesAdvantages & Disadvantages

AdvantagesAdvantages• Pass medium solids. Pass medium solids. • nonpulsating discharge nonpulsating discharge • very little maintenance very little maintenance

DisadvantagesDisadvantages• Requires timing gears. Requires timing gears. • Requires two seals. Requires two seals.

44 . .Materials of ConstructionMaterials of Construction

• Externals (head, casing, bracket)Externals (head, casing, bracket) - Cast iron - Cast iron gearbox and bracket, stainless steel gearbox, 316 gearbox and bracket, stainless steel gearbox, 316 stainless steel head and casing. stainless steel head and casing.

• Internals (rotor, idler)Internals (rotor, idler) - 316 stainless steel lobes and - 316 stainless steel lobes and shaft. shaft.

• Shaft SealShaft Seal - Lipseals, component mechanical seal, - Lipseals, component mechanical seal, double mechanical seal. double mechanical seal.

55 . .ApplicationsApplications

• Food processing. Food processing. • Dairy Produce. Dairy Produce. • Pharmaceutical. Pharmaceutical. • Biotechnology. Biotechnology. • Chemical. Chemical. • Industrial.Industrial.

Circumferential pumpCircumferential pump

External Circumferential pumpExternal Circumferential pump

How the pump worksHow the pump works

Internal Circumferential pumpInternal Circumferential pump

Screw PumpScrew Pump

1. Overview1. Overview Screw pumps are a unique type of rotary positive Screw pumps are a unique type of rotary positive

displacement pump displacement pump the flow through the pumping elements is truly axial the flow through the pumping elements is truly axial has an axial flow pattern and low internal velocities has an axial flow pattern and low internal velocities are classified as two different types: the single rotor are classified as two different types: the single rotor

and the multiple rotor and the multiple rotor

Screw pump can be classified into two Screw pump can be classified into two types:types:

(1) Single Screw Pump(1) Single Screw Pump

(2) Multiple Screw Pump(2) Multiple Screw Pump

, and Multiple Screw Pump may be Twin , and Multiple Screw Pump may be Twin Screw Pump, or Three Screw Pump.Screw Pump, or Three Screw Pump.

((11 ) )Single Screw PumpSingle Screw Pump

FeatureFeature• Applicable for all types Applicable for all types

of liquid of liquid • High reliabilityHigh reliability• Reversible Reversible • self-primingself-priming• Simple and compact Simple and compact

structure,easy structure,easy maintenancemaintenance

StructureStructure

• One rotor inside stator One rotor inside stator • Small number of parts Small number of parts • Material selection to meet various liquid Material selection to meet various liquid

((22 ) )Multiple Screw PumpMultiple Screw Pump

(2.1) Twin Screw (2.1) Twin Screw PumpPump

FeatureFeature• Applicable for all types of Applicable for all types of

liquidliquid• High reliability High reliability • self-priming self-priming

StructureStructure

• No contact between two No contact between two screws screws

• Optimal selection of Optimal selection of material to meet various material to meet various liquid liquid

((2.22.2 ) )Three Screw PumpThree Screw Pump

FeatureFeature• High reliability High reliability • Quiet operation Quiet operation • Small starting torque Small starting torque • Compact and large Compact and large

capacity capacity

StructureStructure

• Rotating elements Rotating elements consist of one power consist of one power rotor and two idler rotor and two idler rotorsrotors

• There is no direct-There is no direct-contact transmission contact transmission of power between of power between rotorsrotors

22 . .How it worksHow it works

33 . .Advantages & DisadvantagesAdvantages & Disadvantages

AdvantagesAdvantages• Wide range of liquids Wide range of liquids

and viscositiesand viscosities• Low internal velocities Low internal velocities • Low mechanical Low mechanical

vibration vibration

DisadvantagesDisadvantages• Relatively high costRelatively high cost• Performance Performance

characteristics sensitive characteristics sensitive to viscosity changeto viscosity change

• Self-priming with good Self-priming with good suction characteristics suction characteristics

• quiet operationquiet operation

• High pressure High pressure capability requires capability requires long pumping long pumping elements elements

44 . .Materials of ConstructionMaterials of Construction

• Rotating partsRotating parts: Tool Steel, Carbon Steel, Monel, etc.: Tool Steel, Carbon Steel, Monel, etc.• CasingCasing: Cast Iron, Ductile Iron, Bronze, Carbon : Cast Iron, Ductile Iron, Bronze, Carbon

Steel, Stainless Steel, Alloy Steel.Steel, Stainless Steel, Alloy Steel.

55 . .ApplicationsApplications

• Raw sewage lift stations Raw sewage lift stations • Sewage plant lift stations Sewage plant lift stations • Stormwater pumping Stormwater pumping • Land Drainage Land Drainage

Reciprocating PumpsReciprocating PumpsINTRODUCTIONINTRODUCTION

A type of positive – displacement A type of positive – displacement pumps which discharge a definite pumps which discharge a definite quantity of liquid during piston or quantity of liquid during piston or plunger movement through the plunger movement through the

stroke distancestroke distance

Basic TheoryBasic Theory

The basic principal of a reciprocating The basic principal of a reciprocating pump is that a solid will displace an pump is that a solid will displace an equal volume of fluid equal volume of fluid

This Solid may be piston or plungerThis Solid may be piston or plunger The volume of the displaced fluid is The volume of the displaced fluid is

equal to the product of the cross equal to the product of the cross sectional area of the plunger or sectional area of the plunger or piston and the height of the strokepiston and the height of the stroke

Reciprocating Pumps

Power Pumps Direct Acting Steam Pumps Diaphragm Pumps

Fixed Stroke Variable Stroke Simplex Duplex

Vertical

Horizontal

Fixed Cylinder Type

Rotary Plunger Type

Power PumpsPower Pumps

1)1) Fixed stroke power pumpsFixed stroke power pumps HorizontalHorizontal VerticalVertical

Vertical pumps are preferred when Vertical pumps are preferred when higher capacity is required and higher capacity is required and small area is presented small area is presented

HorizontalHorizontal

VerticalVertical

2) Variable Stroke2) Variable Stroke Fixed CylinderFixed Cylinder Rotary PlungerRotary Plunger

Fixed CylinderFixed Cylinder

Rotating plungerRotating plunger

Wooble plate Wooble plate

Swash PlateSwash Plate

Radial pistonRadial piston

Direct acting steam pumpDirect acting steam pump

SimplexSimplex

DuplexDuplex

Valves TypesValves Types

The valve type is determined The valve type is determined according to the pump type (Simplex according to the pump type (Simplex or Duplex)or Duplex)

Duplex valve construction is simpler Duplex valve construction is simpler than simplex valvethan simplex valve

In duplex pump the valve of one In duplex pump the valve of one cylinder takes its motion from the cylinder takes its motion from the other cylinderother cylinder

Duplex valveDuplex valve

Simplex ValveSimplex Valve

Diaphragm PumpDiaphragm Pump

Single actingSingle acting

Double actingDouble acting

Pump Maintenance. & Pump Maintenance. &

TroubleshootingTroubleshooting

TroubleshootingTroubleshooting

GeneralGeneral

Pump Problems can be either caused Pump Problems can be either caused by:by:

1. Mechanical Problem with the Pump1. Mechanical Problem with the Pumporor

2. Pump System Problem2. Pump System Problem

Before DetailsBefore Details

The Great Majority of Pump Problems are The Great Majority of Pump Problems are with the Pump Systemwith the Pump System

The Majority of Pump System Problems The Majority of Pump System Problems are on the Suction Sideare on the Suction Side

Pump Problems are usually associated Pump Problems are usually associated with Noisy Operationwith Noisy Operation

ProblemProblem

Drain it

Close both suction and discharge valves and run the pump briefly

Noise continues

Mechanical problem

Noise goes away

System Problem

Debris in the Impeller

Impeller RubbingImpeller out of

BalanceBent or Twisted shaft

Bad bearingsCoupling Misalignment

V-Belt sheave Misalignment

Pipe Stress

Cavitation Vortexing

System ProblemMechanical problem

Before beginning the Before beginning the Troubleshooting processTroubleshooting process

Be sure pressure gages are available for a pump's inlet and discharge

•Temperature gage at the pump inlet

•There should be some method of verifying pump speed through either a hand-held tachometer or strobe tachometer

•Be sure that the drivers are absolutely locked out before removing guards or conducting any system inspections

•Be certain they are fully discharged of liquid before doing any system work

INFORMATION GATHERINGINFORMATION GATHERING

Was the system undergoing routine Was the system undergoing routine maintenance? maintenance?

•Were any new or repaired components changed out?

•When was the pump last serviced? Of what did that service consist?

•What did that service consist?

•What was the appearance and condition of the pump's internal parts?

•From where were replacement parts obtained?

•For recirculating systems such as for lubrication, was new or additional liquid added?

•For one-time-through systems such as fuel oil burners, has the supplier of the fuel, fuel grade or fuel temperature changed?

•How long did the pump operate before the problem presented itself?

Positive Displacement Positive Displacement TroubleshootingTroubleshooting

RotaryRotary Reciprocating

RotaryRotary

Rotary TroubleshootingRotary Troubleshooting

SelectionSelection

When do you need to perform When do you need to perform maintenance on pumpsmaintenance on pumps??

This depends on the pump and the This depends on the pump and the application. In general, diaphragms application. In general, diaphragms on metering pumps last about on metering pumps last about 6 to 12 6 to 12 monthsmonths; gears on gear pumps last ; gears on gear pumps last about about 3 to 6 months3 to 6 months; and motors ; and motors usually last for years. usually last for years.

DC motors require periodic brush DC motors require periodic brush replacement. It is important to replacement. It is important to monitor brush wear; normally brushes monitor brush wear; normally brushes should be replaced every should be replaced every 6 months. 6 months.

RulesRules

BV Rules, Part C, Chapter 1, Section BV Rules, Part C, Chapter 1, Section 10, [6]10, [6]

I.e. Bilge Pumps

Bilge PumpsBilge Pumps Number and arrangement of pumpsNumber and arrangement of pumps

•Use of ejectors•Use of other pumps for bilge duties

•Capacity of the pumps

•Choice of the pumps •Connection of power pump

•Electrical supply of submersible pump motors .