Pump Selection Guideline

GENERAL GUIDELINE FOR PUMP SELECTIONGENERAL GUIDELINE FOR PUMP SELECTIONCLASSIFICATION & CHARACTERISTICCLASSIFICATION & CHARACTERISTIC

PUMPPUMP

DISPLACEMENT TYPECENTRIFUGALCENTRIFUGAL*Note 1

RECIPROCATINGRECIPROCATING*Note 2

ROTARYROTARY *Note 3

*Note 2 : Pressurize or discharge liquid by reciprocating motion of piston or a plunger

*Note1 : Pressurizes liquids by means of centrifugal force of its impeller.

Note 3 : Pressurize or discharge liquid by rotary motion of a gear, a screw or a vane

PERFORMANCE CURVE CHARACTERISTICPERFORMANCE CURVE CHARACTERISTIC

H

QCentrifugal Pump

Q

Pd-Ps

Rotary Pump

Pd-Ps

QReciprocating

Pump

TABLE SHOWING VARIOUS PUMP CHARACTERISTICSTABLE SHOWING VARIOUS PUMP CHARACTERISTICS

CONDITION CENTRIFUGAL PUMP

ROTARY PUMP RECIPROCATING PUMP

1. Discharging state Stable Stable Impulsation

2. For Slurry Can be used with special devices

Not used, in general Not used, in general

3. For viscous fluids Big drop in performance Better in performance

A little drop in performance

4. Pressure Wide range of use Applicable up to intermediate pressure

Wide range of use

5. Capacity Wide range of use (not suitable for small flow)

Not suitable for large flow

Not suitable for large flow

6. When discharge press. increases

Big decrease in flow rate Almost no change in flow rate

Almost no change in flow rate

7. When discharge pressure decreases

Large increase in flow rate



8. Flow rate adjustment

Possible by open/ close of discharge valve or change in speed

Possible by bypass or change in speed

Possible by bypass, or change in speed or stroke length

9. Pressure adjustment

Narrow range of adjustment

Wide range of adjustment

Wide range of adjustment

SCOPESCOPE

CENTRIFUGAL PUMP (Most economical)CENTRIFUGAL PUMP (Most economical)(<100cP)(<100cP)

Small FLOWRATE of 2 to 3m³/Hr up to a large flow rateSmall FLOWRATE of 2 to 3m³/Hr up to a large flow rate Max water head per impeller is determined within the range of nominal Max water head per impeller is determined within the range of nominal

specific speed of the non dimensional number Nsspecific speed of the non dimensional number Ns

RECIPROCATING PUMP (Small flow rate or high differential pressure)RECIPROCATING PUMP (Small flow rate or high differential pressure) Several lit/hr ~Several lit/hr ~ injection pumpinjection pump Several dozen m³/hr ~Several dozen m³/hr ~ multi plunger pumpmulti plunger pump Normally used in high pressure only (Price ↑)Normally used in high pressure only (Price ↑)

Rotary Pump (Viscous Liquids)Rotary Pump (Viscous Liquids) Large range of Q and PLarge range of Q and P Required certain amount of viscosity in the liquid due to gear or screw will Required certain amount of viscosity in the liquid due to gear or screw will

be engaged together at high or middle speed rotationbe engaged together at high or middle speed rotation

CENTRIFUGAL PUMP (CP)CENTRIFUGAL PUMP (CP)

CLASSIFICATION & CHARACTERISTICS OF CPCLASSIFICATION & CHARACTERISTICS OF CP

A.A. BY IMPELLERBY IMPELLER

i.i. Axial flow pumpAxial flow pump

ii.ii. Mixed flow pumpMixed flow pump

iii.iii. Centrifugal pump (Radial Flow)Centrifugal pump (Radial Flow)CLOSED

SEMI OPEN

OPEN TYPE

B.B. BY INSTALLATIONBY INSTALLATION

i.i. Horizontal PumpHorizontal Pump – Mostly used due to economical – Mostly used due to economical & & maintenancemaintenance

ii.ii. Vertical PumpVertical Pump – Application which need higher suction – Application which need higher suction performance (NPSH) performance (NPSH)

iii.iii. In line pumpIn line pump – In the line of piping , used in restricted – In the line of piping , used in restricted installation space installation space

C.C. BY CASINGBY CASING

i.i. Volute pumpVolute pump – Casing made in the form of a spiral or – Casing made in the form of a spiral or volutevolute

ii.ii. Turbine pump Turbine pump – Casing equipped with diffuser – Casing equipped with diffuser (diffuser pump)(diffuser pump)

D.D. By Number of ImpellersBy Number of Impellers

i.i. Single or double stageSingle or double stageii.ii. Multi stageMulti stage

CENTRIFUGAL PUMP (CP)CENTRIFUGAL PUMP (CP)

Application Range of Centrifugal Pumps at 50 Hz AreaApplication Range of Centrifugal Pumps at 50 Hz Area

SPECIAL PUMP

1. Sundyne Pump High speed pump

When single or double stage centrifugal pump cannot covered the application, Sundyne pump shall be considered.

Multi stage performance from a single unit

Small foot print

Simple design

Standard or engineered options

Performance Envelope LMV/BMP SeriesPerformance Envelope LMV/BMP Series

PERFORMANCEPERFORMANCE

2. Non Seal Pump

Pump without shaft seal

Suitable on handling liquid when no leakage allowed

Motor cooling & bearing lubrication are by self liquid

SPECIAL PUMPSPECIAL PUMP

3.3. Magnet Drive PumpsMagnet Drive Pumps Magnetic drive pumps have a single leak containment shell but many Magnetic drive pumps have a single leak containment shell but many

factors lead to containment shell rupture and unpredictable, massive factors lead to containment shell rupture and unpredictable, massive increase in leakage.increase in leakage. 6 pump / frame / motor bearings6 pump / frame / motor bearings CouplingCoupling Alignment critical Alignment critical Vulnerable single leak containment shellVulnerable single leak containment shell No bearing monitorNo bearing monitor

SPECIAL PUMPSPECIAL PUMP

CP SELECTION GUIDELINECP SELECTION GUIDELINE

1)1) Consider the most economical Consider the most economical horizontal typehorizontal type single or double stagesingle or double stagepump within the application.pump within the application.

The pump has the following types;The pump has the following types;

A.A. In Support TypeIn Support Typei.i. Bracket support typeBracket support type

- for water pump / suitable for packing seal- for water pump / suitable for packing seal

ii.ii. Foot support type (for ISO, ANSI - mid class mech. seal)Foot support type (for ISO, ANSI - mid class mech. seal)- ISO [medium duty, designed for 16 bars in - ISO [medium duty, designed for 16 bars in

pressure under pressure under normal temperature]normal temperature]

iii.iii. Centerline supportCenterline support-- for API, high quality, high temperature.for API, high quality, high temperature.-- API – Liquid above 180˚C centerline is API – Liquid above 180˚C centerline is

preferable.preferable.-- designed for min 40 bar at 38˚C designed for min 40 bar at 38˚C

B.B. In Bearing Support TypeIn Bearing Support Type

i.i. Overhung support typeOverhung support type - - Overhung impeller (for Overhung impeller (for single suction single suction pump)pump)

-- When select overhung double When select overhung double stage stage overhung double suction overhung double suction engineer engineer need to give extra need to give extra attention as it is attention as it is prohibited in API.prohibited in API.

ii.ii. Between bearing support typeBetween bearing support type -- Suitable for double suction Suitable for double suction multistage pump. multistage pump.

Need two Need two shaft seals.shaft seals.

Pay attention to :Pay attention to : Client requirementsClient requirements NsNs NPSHNPSH Pressure ratingPressure rating


2)2) Vertical PumpVertical Pump

Used when horizontal pump cannot attain necessary NPSH Used when horizontal pump cannot attain necessary NPSH requirement or its improvement requires a lot of cost.requirement or its improvement requires a lot of cost.

3)3) High Head PumpHigh Head Pump

Before decide Sundyne , investigate the use of multistage pump Before decide Sundyne , investigate the use of multistage pump as well.as well.

4)4) Multi Stage PumpMulti Stage Pump

TypesTypes

A.A. Horizontal multistage pumpHorizontal multistage pump

i.i. Horizontal Split CasingHorizontal Split Casingii.ii. Vertical Split Casing (Ring – segmental type)Vertical Split Casing (Ring – segmental type)iii.iii. Barrel CasingBarrel Casing


B.B. Vertical Multistage PumpVertical Multistage Pump

Generally if NSPH allowed, a horizontal & multistage Generally if NSPH allowed, a horizontal & multistage pump pump should be selected instead of sundyne due to easy should be selected instead of sundyne due to easy maintainability. However under following conditions it is maintainability. However under following conditions it is advised advised not to use horizontal split casing.not to use horizontal split casing.

Liquid temperature > 205˚CLiquid temperature > 205˚C Flammable or toxic liquid with S.G < 0.7Flammable or toxic liquid with S.G < 0.7 Flammable or toxic liquid with discharge pressure ≥ 69 Flammable or toxic liquid with discharge pressure ≥ 69

bars.bars.

API prohibited vertical split casing (ring segmental type) API prohibited vertical split casing (ring segmental type) since it since it cannot be disassembled unless a pump casing is cannot be disassembled unless a pump casing is removed removed from main piping.from main piping.

Normally adopted is many case of BFW due to less price Normally adopted is many case of BFW due to less price compared to Barrel type.compared to Barrel type.


5)5) Non Seal PumpNon Seal Pump

Avoid leakageAvoid leakage

Extreme low temperature (e.g. LNG)Extreme low temperature (e.g. LNG)

Common use (7.5 to 11 kW)Common use (7.5 to 11 kW)


RECIPROCATING PUMP (RP)RECIPROCATING PUMP (RP)

Classification and Characteristics of Reciprocating Pumps

Classification of reciprocating pump is as follows:

Simplex

Max cap : 250 m³/hPd max : 600 bars

Cap : 10 m³/hr

Pd : 500 bars (small plunger diameter)

: 10 bars (large plunger diameter)

-Pressure limitation (Check)

-Temperature is limited to 150˚C

Duplex

Multiplex

Plunger

Piston

Diaphragm

Horizontal

Vertical

ControlledVolume

Simplex

Duplex

Multiplex

Piston

Plunger

Single Acting

Double Acting

Horizontal

Vertical

Power

ReciprocatingPump

RP SELECTION GUIDERP SELECTION GUIDE

Small capacity several Ɩ/hr to several hundred Ɩ/hr , a controlled volume is selected. Unless special process conditions given.

If do not need controlled volume and bigger capacity type shall be decided by comparing cost between power pump & controlled volume pump.

In case used capacity control for power pump, please utilize speed variator or VSC.

Sometime utilize steam (air), where it is called steam (air ) piston pump , application up to 350 m³/hr &15 bars pressure.

ROTARY PUMPROTARY PUMP Classification and Characteristic of Rotary Pump

Vane

Blade, bucket,Roller or

Vane in Rotor Constant Displacement

Variable Displacement

Single Piston

Multi Piston

Constant Displacement

Vane in Stator


Constant Displacement


Slipper

Flexible Tube

Flexible Vane

Flexible Liner

Single

Multiple

Single

MultipleScrew

CircumferentialPiston

External

InternalGear

Single

MultipleLobe

Flexible Member

Axial

Radial

Piston

RotaryPumps

(External gear engagement)

(Internal gear engagement)

Low viscosity liquid also can

used

(Liquid near solid nature)

(Liquid which contain some slurry)

* Widely used . Used handling liquid to lubricate lubricating metal friction.

> 10Cp viscosity is required

**

SCOPESCOPE

Gear Pump Std. pump are for low pressure (max dis.= 10kg/cm²G) Min & medium flow rate (max ≈ 300m³/hr)

Screw Pump For medium / high press. (max 100 kg/cm²G) Medium & large flow rate ( max 1500m³/hr)

RP Selection Guide

1. Viscous liquid ~ rotary pump is preferable

2. Gear pump is the most economical if pressure & flow allows

3. Then if P&Q high screw pump is preferable

Pump Selection Guideline

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