How To Calculate Water Volumes & Flow Rates In Different Units
You will almost certainly at some time or another need to convert volumes or
flow rates from one type of unit system to another. For example gallons in the
UK are not the same as in the USA. In fact 1 imperial gallon is equal to 1.20 US
gallons as you will see from table below.
How To Use This Table
Look for the cell which contains the number 1 (in yellow). Then read across
the row. This is explained below.
This is particularly helpful in
specifying pond and waterfall pumps
|
Unit |
US galls/min |
Imp galls/min |
Cu Feet/min |
Litres/min |
Cu. M/min |
Lbs water/min |
|
US gallons |
1 |
0.83 |
0.13 |
3.79 |
0.004 |
8.3 |
|
Imp Gallons |
1.20 |
1 |
0.16 |
4.55 |
0.005 |
10.0 |
|
Cu Feet |
7.48 |
6.23 |
1 |
28.32 |
0.028 |
62.4 |
|
Litres |
0.26 |
0.22 |
0.04 |
1 |
0.001 |
2.2 |
|
Cu. Metres |
264.20 |
220.00 |
35.32 |
1,000.00 |
1 |
2,202.7 |
Example: for a pump doing 4 litres per minute
what is flow in other units? To get the answer just multiply the
number in the other columns by (in this case) 4 as shown below;
|
|
Litres |
1.06 |
0.88 |
0.14 |
4 |
0.004 |
8.8 |
Expressed another way 4 litres per minute is
the same as the units below
|
|
Flow in |
US gallons/min is |
0.26 |
|
Flow in |
Imp gallons/min is |
0.22 |
|
Flow in |
Cu feet/min is |
0.04 |
|
Flow in |
Cu metres/min is |
0.001 |
|
Weight of water in lbs/min is |
2.20 |
Actual conversion factors read
across eg 1 US gall = 0.1337 cu feet
|
or 1 litre = 0.2642 US gallons, or
0.2200 Imperial gallons
|
|
|
US |
Imp |
Cu Feet |
Litres |
Cu. Metres |
Pounds |
|
Gallons |
Gallons |
|
US |
1 |
0.8327 |
0.1337 |
3.7854 |
0.0038 |
8.3380 |
|
Gallons |
|
Imp |
1.201 |
1 |
0.161 |
4.546 |
0.005 |
10.013 |
|
Gallons |
|
Cu Feet |
7.481 |
6.229 |
1 |
28.317 |
0.028 |
62.371 |
|
Litres |
0.2642 |
0.2200 |
0.0353 |
1 |
0.0010 |
2.2029 |
|
Cu. Metres |
264.2 |
220.0 |
35.3 |
1000.0 |
1 |
2202.7 |
Use to convert flow rates Read
across
|
|
|
US gpm |
Imp gpm |
Cu Metres/hr |
Litres per Hr |
|
US gpm |
1.000 |
0.833 |
0.227 |
227.100 |
|
Imp gpm |
1.201 |
1.000 |
0.273 |
272.900 |
|
Litres per Sec |
0.0044 |
0.0037 |
0.0010 |
1.0000 |
This page reprinted with permission of
The Pond Professor |
