Handbook of Civil Engineering Calculations

Discharge flow

Usual maximum

suction lift, ft (m)

Liquids handled

Discharge pressure

range

Usual capacity range

How increased head
affects:
Capacity
Power input

How decreased head

affects:

Capacity

Power input

Centrifugal

Volute

and

diffuser

Steady

15 (4.6)

Axial

flow

Steady

15 (4.6)

Clean, clear; dirty,

abrasive; liquids

with high solids

content

Low to high

Small to largest

available

Decrease

Depends on specific

speed

Increase

Depends on specific

speed

Rotary

Screw

and

gear

Steady

22 (6.7)

Viscous;

non-

abrasive

Medium

Small to

medium

None

Increase

None

Decrease

Reciprocating

Direct

acting

steam

Pulsating

22 (6.7)

Double

acting

power

Pulsating

22 (6.7)

Triplex

Pulsating

22 (6.7)

Clean and clear

Low to highest produced

Relatively small

Decrease

Increase

Small

increase

Decrease

None

Increase

None

Decrease

None

Increase

None

Decrease

Size

gal/min

3CL:

200

300

400

500

4 C:

400

600

800

L/s

12.6

18.9

25.2

31.5

25.2

37.9

50.5

Total head

20ft.

4/min — hp

910—1.3

1000—1.9

1200—3.1

—

940—2.4

1080—4

—

6.1m,

r/min— kW

910—0.97

1000—1.41

1200—2.31

—

940—1.79

1080—2.98

—

25ft,

r/min — hp

1010—1.6

1100—2.4

1230—3.7

—

1040—3

1170—4.6

—

7.6m,

r/min— kW

1010—1.19

1100—1.79

1230—2.76

—

1040—2.24

1170—3.43

—

TABLE 5. Characteristics of Modern Pumps

TABLE 6. Typical Centrifugal-Pump Rating Table

Example: 1080—4 indicates pump speed is 1080 r/min; actual input required to operate the
pump is 4 hp (2.98 kW).
Source: Condensed from data of Goulds Pumps, Inc.; SI values added by handbook editor.