[Oto-Hui.com]en - Hydraulic Courses

HYDRAULICTRAINING COURSE

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PRESSURECommon unit : bar1 bar = 1,02 kgf/cm²

= 1 daN/cm²= 10 N/cm²= 0,99 atm= 105 Pa (Pascal)= about 10 m of water column (wC)= 751 mmHg

ENERGYUnits : Heating -> thermy/hour (th/h)

Cooling -> frigory/hour (fg/h)

1 th/h = 1000 kcal/h= 1,163 kW/h

1 fg/h = -103 cal/h= -1 kcal/h

1 kW/h = 860 kcal/h

MOTOR POWERUnits : Watt (W) - kiloWatt (kW)

1 kW =1000 W= 1,36 hp (horse power)

1 hp = 736 W

See also the page "definition of the power"

ABSOLUTE PRESSUREIs equal to the gauge pressure (or relative) plus the atmosphericpressure (1 bar at sea level)Starts at absolute zero

GAUGE PRESSUREIs reading pressure gaugeStarts at atmospheric pressure

An gauge pressure of 5 bar, makes 5+1= 6 bar absolute

Usually, pressure gauge are in gauge pressure.

Units - Part 1

EN hydraulic courses.xls Units Page 2

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TEMPERATURE DIFFERENCE (∆t)

Is the pressure difference between the inlet and the oulet of the boiler

HEATING POWER

Is the quantity of heat produced by a generator, during the time unit.for water with :P = heating power in kcal/hQ = water flow in litres/hour (l/h)

FLOW

Is the water volume circulating during the time unit.P∆t

Q = water flow in litres/hour (l/h)P = heating power in kcal/h

STATIC HEAD (Hs)

STATIC PRESSURE(Suction head)

Is equal at Hg + 0,5 to 1 bar depending of the network temperature.

NB : it is necessary to have a static pressure at the suction of the pump higher thanNB : pump NPSHr specialy in open networks or roof installations.

Is the difference of level between the highest and thelowest points of the network.

Is required for calculating the static pressure of thenetwork.

HEATING - AIR CONDITIONING

∆T = Toutlet - Tinlet

P = Q x ∆t

Q=

Units - Part 2

C

Hs

EN hydraulic courses.xls Units 2 Page 3

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Given Unit Multiply by required unit Given Unit Multiply by required unit

* SG is for Specific Gravity - pure water SG is 1 g/cm³

Flow velocity through circular pipe (m/s) =

Shaft power Input (kW) =

Full load current for 3 phase motor (A) =

Full load current for 1 phase motor (A) =

Synchronous speed =

Direct on line Star-delta130% 43%600% 200%Starting current as % of FL current

CONVERSION FACTORS

FLOW HEAD

Starting torque as % of FL torque

0,278 l/s

m³/h m3,670 gpm4,400 USgpm

16,667 l/min

1.42 x SG psi0.1 x SG

0.098 x SG bar3,281 ft

9.8 x SG kPa kg/cm²

l/s

60,000 l/min

bar

10.211 / SG m33.5 / SG ft13,200 gpm 14,5 psi15,838 USgpm 1,02 kg/cm²

3,600 m³/h 100 kPa

USEFUL FORMULAS for centrifugal, mix-flow and Axial flow pumps

bar0,833 gpm 0.433 x SG psi0,063 0.03 x SG kg/cm²0,227 m³/h 2.988 x SG kPa

Usgpm

3,788 l/min

ft l/s

0,305 m0.03 x SG

gpm

4,546 l/min

psi1,200 USgpm0.703 / SG m

0,069 bar2.31 / SG ft0,076 l/s 0,07 kg/cm²

0,273 m³/h 6,9 kPa

l/min

0,220 gpm

kg/cm²0,264 USgpm10 / SG m0,981 bar

32.81 / SG ft0,017 l/s 14,22 psi0,060 m³/h 98 kPa

Units - Part 3

m³/h x metres head x SGPump efficiency (η) x 367

m³/h x 353.7(pipe internal diameter in mm)²

motor kW x 100√3 x efficiency (η) x Volt x power factor (cos ϕ)

motor kW x 100efficiency (η) x Volt x power factor (cos ϕ)

Frequency (Hz) x 120Number of pole

EN hydraulic courses.xls Units 3 Page 4

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Id.

kW absorbedMotor efficiency (η)

P2>Hydraulic input power

kW abs = P1 x η (motor efficiency)

Q (m3/h) x H (m) x SG367 x η (pump efficiency)

Exemple 1 - P1 determination Exemple 2

Pump : Water - SG = 1 Testing platformFlow : 100 m3/h - Head : 19m Measured data :Pump efficiency : 75%

Flow 130 m3/h - Head 22 mWCP.abs.Hyd = (100x19)x1/(367x0,75) = 6,90 kW U = 400 V - I = 19,7 A

Data : motor cos ϕ : 88%

OPTION 1 P1=400x19,7x1,732x0,88 = 12010WP1 = 12 kW

Selected motor : P2 = 7,5 kWMotor efficiency η : 83% kW abs. = 12 x 0,87 = 10,44 kW

P1 = 6,9 / 0,83 = 8,31 kW

Pump efficiency =OPTION 2 η = (130x22) / (367x10,44) = 0,746

η = 74,6%Selected motor : P2 = 9 kW

Motor efficiency η : 85%P1 = 6,9 / 0,85 = 8,12 kW

DefinitionElectrical input power for thepower supply, or consump-tion. It is what ones pays.

P1

kW

=

Power absorbed by pump. Forthe motor also called "utilpower"

Motor normalized nominalpower. For a fixed frecuency,it is the power available atmotor shaft.

P2 Is to be choosen higher than the hydraulic input power.

kW

P1 = U . I . V3 . Cos ϕ (in Watt)

P1 =

Formula

kW

Power definition in three phase

Electrical panelXXXX

kWh

Motor

EN hydraulic courses.xls Power Page 5

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Friction losses curves

DN50Head

Flow12 m3/h

48 mm/m

12 mm/m

6 m3/h

DN50Head

Flow

38 mm/m

12 mm/m

6 m3/h

DN40

EN hydraulic courses.xls f.l. Page 6

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Friction losses in serie

FILTERVALVE

Head

Flow

Total friction losses

J1+J2

J2

J1

Valve friction losses

Filter friction losses

EN hydraulic courses.xls serie f.l. Page 7

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Friction losses in parallel

FILTER J2

VALVE J1

Head

Flow

J2

J

J = J1 = J2

J1

Q Q

Q1

Q2

Q1 Q2 Q=Q1+Q2

EN hydraulic courses.xls paralel f.l. Page 8

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Pump's hydraulic characteristic : closed loop

Total Head

Duty point

Flow supplied by the pump

Pump's curveFriction

losses curve

Head supplied

by the pump

Flow

EN hydraulic courses.xls f.l.-closed Page 9

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Pump's hydraulic characteristic : open loop

Total Head

Duty point

Flow supplied by the pump

Pump's curveFriction

losses curve

Head supplied

by the pump

Flow

Friction losses

Geometrical height

EN hydraulic courses.xls f.l.-open Page 10

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ù

Risks :Noise in the pipeworkHigher NPSHn requestedMore power consumptionFaster wear

Solutions :Trim the impeller diameterIncrease the friction losses (diaphram, valves)Reduce the speed

Over estimation of friction losses - Closed loop

Calculated duty

Total Head

Pump 1 duty point

Calculated flow

Pump 1

Pump 2

Calculated friction looses

Real friction looses

Pump 2 duty point

Over-flow

EN hydraulic courses.xls f.l.-risks-closed Page 11

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Risks :Noise in the pipeworkHigher NPSHn requestedMore power consumptionFaster wear

Solutions :Trim the impeller diameterIncrease the friction losses (diaphram, valves)Reduce the speed

Over estimation of friction losses - Open loop

Calculated duty

Total Head

Pump 1 duty point

Hg

Pump 1

Pump 2

Calculated friction looses


Pump 2 duty point

Over flow


Calculated flow

EN hydraulic courses.xls f.l.-risks-open Page 12

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NPSHa : Net Positive Suction Head available, depends on the installation.

NPSHr : Net Positive Suction Head requested, depends on the pump.(given by the pump manufacturer).

MSC : Maximum Suction Capacity

TH : Total Head

=> NPSHa = ( Patm - Pv ) / SG - Hs - Js

=> TH = Hs + Js + Hd + Jd + Pr

=> MSC = Patm - NPSHr

CAUTION :NPSHa > NPSHr - minimum 0,5 to 1 meterCAVITATION risk if NPSHa < NPSHrMSC > Ha + Ja - minimum 0,5 to 1 meterIf temperature increases, MSC decreasesIf altitude increases (Patm decreases), MSC decreases

Negative suction lift

Hs

Js

HdJd

Pr

EN hydraulic courses.xls negative suction lift Page 13

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NPSHa : Net Positive Suction Head available, depends on the installation.

NPSHr : Net Positive Suction Head requested, depends on the pump.(given by the pump manufacturer).

MSC : Maximum Suction Capacity

TH : Total Head

=> NPSHa = ( Patm - Pv ) / SG + Hc - Js

=> TH = - Hc + Js + Hd + Jd + Pr

=> MSC = Patm - NPSHr

CAUTION :NPSHa > NPSHr - minimum 0,5 to 1 meterCAVITATION risk if NPSHa < NPSHrMSC > Ha + Ja - minimum 0,5 to 1 meterIf temperature increases, MSC decreasesIf altitude increases (Patm decreases), MSC decreases

Positive suction lift

Hc

Js

HdJd

Pr

EN hydraulic courses.xls positive suction lift Page 14

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Same pumps in serie

Head

Flow

Pump 1H1

QHead

Flow

Pump 2H2

Q

Head

Flow

Pumps 1 + 2H1+H2

Q

EN hydraulic courses.xls Same pumps in serie Page 15

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Same pumps in parallel

Head

Flow

Pump 1H

Q1

Head

Flow

Pumps 1 + 2

H

Q1+Q2

Q Q

Q1

Q2

Head

Flow

Pump 2H

Q2

EN hydraulic courses.xls Same pumps in parallel Page 16

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Different pumps in serie

Head

Flow

Pump 1H1

Head

Flow

Pump 2H2

Q

Q

Head

Flow

Pump 1 + 2H1+H2

Q

EN hydraulic courses.xls Different pumps in serie Page 17

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Different pumps in parallel

Head

Flow

Pump 1H

Q1

Head

Flow

Pumps 1 + 2

H

Q1+Q2

Q Q

Q1

Q2

Head

Flow

Pump 2H

Q2

EN hydraulic courses.xls Different pumps in parallel Page 18

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b/ When the pumped fluid reaching the pump entrace is close to vapor point.

In each installation it is necessary to ensure NPSHa is greater than NPSHr.

NPSH curse according flow

The pump's suction capacity is defined by the NPSH (Net Positive Suction Head).

NPSH is a measurement of the difference between the local net pressure and pumped liquid'svapor pressure (Hva)

It is one of the essential parameters to take into account when selecting a centrifugal pump in thefollowing cases :

a/ When the pumped water level is below the pump shaft.

NPSH

Flowm3/h

4

3

2

1

1 2 3 4 5

EN hydraulic courses.xls NPSH curve Page 19

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a/ Pump drawing cold water from a tank at atmospheric pressure :

b/ Pump sucking from a pressurized tankPo - Pv

SG

M.S.C. : Maximum Suction CapacityPo : Absolute pressure in the suction tank (in bar)Pv : Vapor tension of the pumped liquid at the pumped temperature (in bar)SG : Specific Gravity - pure water SG is 1 g/cm³

- NPSHr

Is determinated by the pump manufacturer ; it depends of the pump type, the impeller diameter,the flow and the pump speed.The NPSHr (requested) of a pump, given in meters of liquid, indicates the minimum absolutepressure necessary at the pump's suction for correct running.

NPSHr enables the pump's MSC (Maximum suction capacity)to be calculated. The MSC is givenin meters of water and indicates the height above which a pump is able to draw water and pumpnormally.

M.S.C. = Patm - NPSHr

M.S.C. = 10 x .

NPSH required

Complete emptyness

10,33 mmaximum

NPSHr

M.S.C. Atmospheric pressure

Atmospheric pressure

EN hydraulic courses.xls NPSHr Page 20

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The security range is to be between 0,5 to 1 m head depending on the pump.

Pa - Pv Va²SG 2g

NPSHa in metersPa : Absolute pressure at the pump's suction.Pv : Vapor tension of the pumped fluid.SG : Specific Gravity - pure water SG is 1 g/cm³Va : Speed at the pump suctiong : gravity acceleration

ha : suction geometric headJa : Suction piing network's total friction looses

+

NPSHa at pump suction depends on individual installation (fluid's nature and pressure,temperature, vapor tension, altitude, diameter and shape of the pipes, etc.). It is totallyindependent of the pump.The NPSH available is equal to the absolute pressure at the suction flange over the vaporizationpressure of the fluid.

IN order to have the installation running properly, it is mandatory to have the NPSHavailable a the pump's suction higher than the NPSH necessary for the same pump.

NPSH available > NPSH required

NPSHa = 10 x

NPSH available

0,5 a 1 m

NPSHn

M.S.C.

ha

Ja

Pv

M.S.H.

NPSHa

Atmospheric pressure

Absolute zero

NPSH necessary (for the pump)

NPSH available(from the instalation)

EN hydraulic courses.xls NPSHa Page 21

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Pump cavitation

Flow

Head

Head 1Head 2

NPSHAtm. pressure / ρ

NPSHa

NPSHn

Pv / ρ

ha

Ja

Flow

CavitationGood running

EN hydraulic courses.xls Cavitation Page 22

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Glandless pump installation

01 2 3

4 01 2 3

4

Expansion vessel

Boiler Radiador

Head

Pump's suction

head

Pump Friction looses

Expansion tank's static pressure

Pump's discharge

head

Pressure diferential

(read at the pressure gauge)

EN hydraulic courses.xls Installation Page 23

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1. Instal the circulator with the shaft perfectly horizontal

2. Drain at the first starting

3. Check the rotation direction for the three phase motors

4.

5.

6.

7.

8.

9.

10. Remove the circulator during chemical sludge removing operations.

When the glandless pump isn't running, even for a long time, keep it in the water (with glycol ifnecessary).

Make sure the glandless pump is rotating freely before starting it after a long period of timewithout running.

Make sure the input current is compatible with the current indicated on the motor.

Electrical protection is requested for single phase motors from 100W and mandatoy for allthree phase motors.

Check the Total Dynamic Head and adjust the glandless pump at the correct speed (avoid touse the circulator at the curves extermities).

Make sure to have the minimum head requested according the temperature (static pressure).

Recommendations for a glandless pump's installation

Valve

Valve

Drain

Pressure gauge

Suction head

Discharge head

This is the total dynamic head

EN hydraulic courses.xls Recommendations Page 24

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90°C 110°C 130°CNSB 3 10NXL12 - NZL12 - NXL15 - NXL30 - NXL50NYV12 - NYL12 - NYL30 - DYL30 3XA15NV - C1026NV 95°C maxi

NXV12 - ZOON225XV for MXV12 10CXL50 and

CXL2025 - CXL2050 ZOOM225XV

ZOOM225NXL - ZOOM260LCXL70 - CXL80CXL2070 - CXL2080C2400NBCXL100 - CXL2100 - ZOOM 245NXAV - ZOOM260NXAV - ZOOM300L - ZOOM300NBZOOM320C 10 17 30(E)C1115(N) - (E)C1116(N) - (E)C1120(N) - (E)C1210(N) - (E)C1220(N) - (E)C1313(N) - (E)C1513(N) -(E)C2500(N) - (E)C2650(N)(E)C1230(N) - (E)C1420(N) - (E)C2655(N) 6 13 26(E)C1240(N) - (E)C1430(N)(1) - (E)C1440(N)(1)(E)C2800(1)(N) - (E)C2805(N)(6)ECX1400 - ECX1401 - ECX1500 -ECX2400 - ECX2500ECX1501 - ECX1650 - ECX1653 - ECX 1654 - ECX1655 -ECX2501 - ECX2650 - ECX2653 - ECX2654ECX1800 - CX1801B - CX1802B -ECX2800 - CX2801B - CX2802BSCX - SXM 32-80SCX - DCX - SXM - DXM 50-90SCX - DCX - SXM - DXM 40-40 et 65-50 9 16 29SCX - DCX - SXM - DXM 40-80 13 20 33SCX - DCX - SXM - DXM 50-25 ET 65-25 7 14 27SCX - DCX - SXM - DXM 50-50 ET 80-25 11 18 31SCX - DCX 80-50 14 21 34SCX - DCX 65-90SX - DX 1801-1802-2801-2802

Glandless pump model Minimum pressure according temperature

5 12

6 13

4 11 24

10 17 30

6 13 26

10 17 30

16 23 36

12 19 32

16 23 36

Glandless pumps' suction minimum pressure

EN hydraulic courses.xls Min pressure Page 25

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PUMP SELECTION - THE FIRST QUESTIONSWater loop Water supply Drainage - Sewage

Climatisation Surface Submerged Rain water Sewage water CorrosiveHeating (water level (water level Dirty water water

under 7 m) over 7 m)1 - flow in m3/h ( Q ) X X X X X X

or- Heating power ( kCal/h or kW or th/h) X

and Q l/h=kCal/h t- Temperature difference ( °C ) X

2 - Total Head (in meters) X X X X X XIf unknowed, installation details

- Open circuit- Suction height or suction load in m X

length in m Xdiameter in mm X

- discharge height in m X X X X Xlength in m X X X X Xdiameter in mm X X X X XResidual pressure in bar X X

- Loops- Total loop length X- diameter in mm X

3 - Maximum service pressure or static pressure - bar X X X

4 - Altitude on the installation in meters X X

5 - Pumped fluid- Type X X X X- temperature X X X X X X

6 - Remplacement- Dimension between unions or flanges X- Existing pipes diameter X

7 - Type of voltage- Single phase - 230 V X X X X X X- Three phase - 230 V X X X X X X- Three phase - 400 V X X X X X X

Document interne Salmson - Reproduction interdite

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QUESTIONNAIRE FOR THE STUDYOF A PUMPING INSTALATION

Name (or company) Adress

Correspondant Zip code CityActivity Tel Fax

Pumped liquid : INSTALLATION DETAILSNATURE………………….………… a Suction DischargeClear ..a Laden…a if laden, nature …a ¤ Height between the lower ¤ Height between the higherDensity……a Temperature (°C)…….. a ¤ water level and suction port ¤ water level and discharge portIn case of replacement of a pump, indicate : ¤ ha ………………. m ¤ hr ……………….. m- Brand, type, motor capacity : ¤ Storage tank height ¤ Total pipe length- Hydraulic characteristics : ¤ hc ……………….. m ¤ lr ………………… m

¤ Total pipe length ¤ Pipe diametre Pumping origin and location: ¤ la ………………… m ¤ dr……………. Φ mmRiver………………….. a Bore hole Φ ……a Pit Φ…. a ¤ Pipe diametre ¤ lower water level Tank under pressure …a City water … a Pressure (bar) ¤ da ……...……. Φ mm ¤ hn ………………. mAltitude (if higher than 1000m) ……………...…… a m ¤ Stainer or ¤ Valves ……..…… nb

¤ check valve ¤ Elbows …………. nb Installation type: (see drawings below) ¤ FilterSuction A1 A2 A3 A4 ¤ Valves …………… nbDischarge R1 R2 R3 ¤ Elbows ………….. nb

Hydraulics requirements:Flow (m3/h) ………..………………………………………………. a MOTOR :Make sure the origin flow is sufficuent) ¤ Available voltage:Expected pressure at the last tap …………………………… RP 230 V - 1 ph … a 230 V - 3 ph … a 400 V - 3 ph … aNumber of persons ………………………………………………. am² to water ………………………………………………………… a 50 Hz …………a 60 Hz …………aBladder vessel ……………………………………………… litres

SELECTED PUMP:Flow (m3/h) Head (mWC) Ports Φ Motor kW

Maximum suction head 7m

(friction looses inc.)

Suction head above 7m

borehole or pit

Storage tankpressure A2 or

town water supply A3

Surface pump Immerged pump

SUCTION

Atmospheric pressure storage tank

Atmospheric pressure storage tank or sewage

Under pressure bladder vessel

Surface or immerged pumps Drainage-Sewage

DISCHARGE

yes no

yes no

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TYPE OF INSTALLATION AND ACCESSORIES

A1 - R1 A1 - R2 A2 - R1 A2 - R2

A3 - R1 A3 - R2 A4 - R1 A4 - R2

R3TYPE OF INSTALLATION :

select qty unit price total price¤ PUMP TYPE :

¤ Accessories : (to select on the drawings of this page)

¤ 1 Strainer Φ or suction kit¤ 2 Check Valve Φ¤ 3 Suction valve Φ or by-pass valve¤ 4 Discharge valve Φ¤ 5 Relief valve¤ 6 Bladder vessel - Capacity litres¤ 7 Automatisation pressure switch¤ 8 Automitasation float switch¤ 9 Dry running protection by float switch your distributor :

¤ 10 Dry running protection by pressure switch¤ 11 Electrical cable and junction¤ 12 Dry running electrode and cable¤ 13 Motor and dry running protection¤ 14 Protection and automatisation circuit breaker¤ 15 Over-flow alarm bell

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Network temperature : Discharge : ………….90°CSuction : ………………70°C

Which are the static pressure in both case :

Case 1

Case 2

Justify your answer

Case 1 : Case 2 :

Static pressure determination

Case 2Geometric head : 3,5 m

Case 1Geometric head : 20 m

Exercice : Static pressure

BB

EN hydraulic courses.xls ex - Static pressure Page 29

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Draw an installation allowing to fill and drain alternatively each one of the tanks to the other withonly one pump.

Exercice : Tank filling and emptying

EN hydraulic courses.xls ex - Filling and emptying Page 30

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Variable level Constant level

10 m 10 m

0 m

Draw the pump's running rangeChoose the right pump in the catalogue.

Graphic solution required

friction looses in the pipe network : 8 m a 100m3/hRequested flow : 100 m3/h

Exercice : Water transfert

0

2

4

6

8

10

12

14

16

18

20

22

24

26

0 25 50 75 100 125

mWC

m3/h

EN hydraulic courses.xls ex - Water transfert Page 31

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1-

2-What is the flow for one pump running alone ?What is the flow for two pumps running in parallel ?

3-What would be the maximum flow for 2 pumps in parallel

Choose the right pump in the catalogue.

For a different network, keeping the possibility to have one or two pumps running,

Closed loop

The drawing below represents the curve of two identical pumps running in parallel.Draw the curve for only one pump running.

Friction losses in the loop for one pump running is 20 m head.

Exercice : Two pumps running in parallel

02468

1012141618202224262830323436

0 10 20 30 40 50 60 70 80 90 100 110 120

m Head

m3/h

2 pumps running

EN hydraulic courses.xls ex - 2 p. paral closed Page 32

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1-

2-

3-


What's the flow for two pumps in parallel?

Friction losses for one pump running is 8 m

Open network

The hereunder drawing represents the curve for 2 pumps running in parallelThe geometric head is 16 m

What's the flow for one pump?Friction losses for one pump running is 4 m

What's the flow for two pumps in parallel?

What's the flow for one pump?


02468

1012141618202224262830323436

0 10 20 30 40 50 60 70 80 90 100 110 120

m Head

m3/h

EN hydraulic courses.xls ex - 2 p. paral open Page 33

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1-

2-

What's the pump's speed for a duty of 110 m 3/h at 14m head ?

What's the input power at 110 m3/h @ 14 m head with a 2 points reduction of the efficiency?

Pump's speed calculation

The hereunder graph represents a pump curve at 3000 rpm.

The efficiency for the equivalent duty on the original curve is of 75%.

Exercice : Speed variation

0

2

4

6

8

10

12

14

16

18

20

22

24

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150

m Head

m3/h

EN hydraulic courses.xls ex - Speed variation Page 34

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1- An installation requires a flow of 150 M3/H and a head of 53 mWCSuction head is 3 mPumped fluid : water, temperature of 10°C, sea levelSuction pipes : Ø125 mmDischarge pipes : Ø100 mm

The duty point has to be respectedThe impeller diameter can be adjusted

Choose with the help of the 4 following curves the most economic solution

2-

Nota :

Liquid Density Q (m3/h) Head (m) NPSHaP3

(kW)P2

(kW)P1

(kW)

Cost for 8000h at 0,60 F per

kWh

Water 1 150 53

Gasoil 0,85 150 53

Soda 1,4 150 53

3- Is the selected pump able to transport in the conditions defined at point 1 the diferent liquidsregardless the material matters?

For the power caculation, a 90% motor efficiency is admitted whatever the load is.

Define the elements characterizing the pump and the installation with the following conditions,without changing the viscosity

Exercice : Power - Power input

EN hydraulic courses.xls ex - Power consumption Page 35

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Etabli par:

ROINSOLLEVisa:Vérifié par:

CORDELLIER

Visa:

ED01 : 04.02.94

ED02 : 04.12.96

AC073090/ML

ED03 : 24.06.97

AC073438/ML

ED04 : 06.09.99

AC074185/BR

719565

6580

2920 TR/MN RPMNO 65-200V

50 HZPALIER BEARING

Ed04 1/1

ESSAIS :TEST CONDITIONS : 5986848C

DENSITE : 1VISCOSITE : 1 CST

H10 ARBRE SHAFT 24 ASP/SUCT.

REF/DISCH.

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Etabli par:


CORDELLIER

Visa:

ED01 : 04.02.94

ED02 : 04.12.96

AC073090/ML

ED03 : 24.06.97

AC073438/ML

ED04 : 06.09.99

AC074185/BR

719566

6580


50 HZPALIER BEARING

Ed04 1/1




REF/DISCH.

www.oto-hui.com

Etabli par:


CORDELLIER

Visa:

ED01 : 04.02.94

ED02 : 04.12.96

AC073090/ML

ED03 : 24.06.97

AC073438/ML

ED04 : 06.09.99

AC074185/BR

719568

80100


50 HZPALIER BEARING

Ed04 1/1




REF/DISCH.

www.oto-hui.com

Etabli par:


CORDELLIER

Visa:

ED01 : 04.02.94

ED02 : 04.12.96

AC073090/ML

ED03 : 24.06.97

AC073438/ML

ED04 : 06.09.99

AC074185/BR

Ed04 1/1719570

100125


50 HZPALIER BEARING H21 ARBRE

SHAFT 32 ASP/SUCT.

REF/DISCH.



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Network temperature : Discharge : ………….90°CSuction : ………………70°C

Which are the static pressure in both case :

Case 1 2,8 b 27,7m

Case 2 1,4 b 13,6 m

Justify your answer

Case 1 : 20 + 4,7 + 3 = 27,7 m (4,7 of vapor tension , 3 of security margin)Case 2 : 3,5 + 7,1 + 3 = 13,6 m (7,1 of vapor tension , 3 of security margin)

Static pressure determination

Case 2Geometric head : 3,5 m

Case 1Geometric head : 20 m

Exercice : Static pressure

BB

SOLUTION

EN hydraulic courses.xls Solution - Static pressure Page 40

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Draw an installation allowing to fill and drain alternatively each one of the tanks to the other withonly one pump.

Exercice : Tank filling and emptyingSOLUTION

EN hydraulic courses.xls Solution - Filling and emptying Page 41

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Variable level Constant level

10 m 10 m

0 m

Draw the pump's running rangeChoose the right pump in the catalogue.

Graphic solution required

friction looses in the pipe network : 8 m a 100m3/hRequested flow : 100 m3/h

Exercice : Water transfert

0

2

4

6

8

10

12

14

16

18

20

22

24

26

0 25 50 75 100 125

The pump will operate in this area

mWC

m3/h

SOLUTION

EN hydraulic courses.xls Solution - Water transfert Page 42

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1-

2-What is the flow for one pump running alone ? 50 m3/hWhat is the flow for two pumps running in parallel ? 57,5 m3/h

3-What would be the maximum flow for 2 pumps in parallel 65 m3/h


For a different network, keeping the possibility to have one or two pumps running,

Closed loop

The drawing below represents the curve of two identical pumps running in parallel.Draw the curve for only one pump running.

The friction looses in the loop for one pump running is 20 m head.


02468

1012141618202224262830323436

0 10 20 30 40 50 60 70 80 90 100 110 120

m Head

m3/h

1 pump running

2 pumps running

SOLUTION

EN hydraulic courses.xls Solution - 2 p. paral closed Page 43

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The hereunder drawing represents the curve for 2 pumps running in parallelThe geometric head is 16 m

1-What's the flow for one pump? 50 m3/hWhat's the flow for two pumps in parallel? 72 m3/h

2-What's the flow for one pump? 38 m3/hWhat's the flow for two pumps in parallel? 46 m3/h


Open network




02468

1012141618202224262830323436

0 10 20 30 40 50 60 70 80 90 100 110 120

m Head

m3/h

SOLUTION

EN hydraulic courses.xls Solution - 2 p. paral open Page 44

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1-2-

Calculation : head at 110m3/h = 20 m, ratio is :

Speed :

Check : Corresponding head : 110 x 1.195 = 131.45 m3/hCorresponding flow : 14 x 1.195 x 1.195 = 20 m head

Correction : Draw the line between the calculated point and the required point, it crossesthe original curve at 125 m3/h @ 18 m head.131,45 / 125 = 1,0516New speed : 2 510 * 1,0516 = 2 640 rpm

Check : 3000 / 2640 = 1,136flow 110 x 1,136 = 124,96 m3/h Head 14 x 1,136 x 1,136 = 18,06 m head.

Power :

What's the input power at 110 m3/h @ 14 m head with a 2 points reduction of the efficiency?

The speed extrapolation gives a duty point higher than the original curve, so the speed difference is too high.

Pump's speed calculationThe hereunder graph represents a pump curve at 3000 rpm.

The efficiency for the equivalent duty on the original curve is of 75%.What's the pump's speed for a duty of 110 m3/h at 14m head ?

Exercice : Speed variation

0

2

4

6

8

10

12

14

16

18

20

22

24

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150

m Head

m3/h

195,11420

=

rpm2510195,13000

=

kW75,573,036714110

=××

SOLUTION

EN hydraulic courses.xls Solution - Speed variation Page 45

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1- An installation requires a flow of 150 M3/H and a head of 53 mWCSuction head is 3 mPumped fluid : water, temperature of 10°C, sea levelSuction pipes : Ø125 mmDischarge pipes : Ø100 mm

The duty point has to be respectedThe impeller diameter can be adjusted

Choose with the help of the 4 following curves the most economic solutionChoice : NO65-200 with a Ø214 impeller - NPSHr of 6,5 m

2-

Nota :

Liquid Density Q (m3/h) Head (m) NPSHaP3

(kW)P2

(kW)P1

(kW)

Cost for 8000h at 0,60 F per

kWh

Water 1 150 53 7,33 27,42 30 or 37 30,47 146 242 F

Gasoil 0,85 150 53 9,15 23,31 30 25,9 124 306 F

Soda 1,4 150 53 4,38 38,39 45 42,65 204 739 F

3-

NO, THE NPSH AVAILABLE FOR THE SODA IS BELOW NPSH REQUESTED

Is the selected pump able to transport in the conditions defined at point 1 the diferent liquidsregardless the material matters?

For the power caculation, a 90% motor efficiency is admitted whatever the load is.

Define the elements characterizing the pump and the installation with the following conditions,without changing the viscosity

Exercice : Power - Power inputSOLUTION

EN hydraulic courses.xls Solution - Power consumption Page 46

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Etabli par:


CORDELLIER

Visa:

ED01 : 04.02.94

ED02 : 04.12.96

AC073090/ML

ED03 : 24.06.97

AC073438/ML

ED04 : 06.09.99

AC074185/BR


REF/DISCH.



719565

6580


50 HZPALIER BEARING

Ed04 1/1

6,5 m

53 m

150 m

27,42kW

SOLUTION

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