When choosing a hose or tube Parker has created the STAMP method. Stamp Stands for:

S: Size     T: Temperature     A: Application     M: Media     P: Pressure

When choosing the size of the tube or hose it is important to know the flow requirements and the Application. Below is the chart provided on page T5 of Parker Industrial Tube Fitting catalog #4300. On this chart you will see that there are different recommendations depending on whether you are sizing a Pressure Line, a Return Line, or a Suction Line.

Again, we have to stress that application plays a vital role in selecting the flow diameter. Choosing the wrong size on the pressure line can create excess heat in the system, the wrong size on the suction line can starve the pump of liquid, or choosing the wrong size on the return line can create a backpressure on the system.

To help size your next system get in touch with one of our technical experts on our sales team or visit a local Parker Store.

MAXIMUMUM
FLOW RATE GPM

RECOMMENDED FLOW DIAMETER IN INCHES
PRESSURE LINES RETURN LINES

SUCTION LINES

0.25

0.064 0.101 0.16
0.5 0.091 0.143

0.226

0.75

0.111 0.175 0.277

1

0.128 0.202

0.32

1.25

0.143 0.226

0.358

1.5

0.157 0.247

0.392

1.75

0.169 0.267

0.423

2 0.181 0.286

0.453

2.5

0.202 0.319 0.506

3

0.222 0.35

0.554

3.5 0.239 0.378

0.599

4

0.256 0.404 0.64
4.5 0.272 0.429

0.679

5

0.286 0.452 0.716
5.5 0.3 0.474

0.75

6

0.314 0.495 0.784
6.5 0.326 0.515

0.816

7

0.339 0.534 0.847
7.5 0.351 0.553

0.876

8

0.362 0.571 0.905
8.5 0.373 0.589

0.933

9

0.384 0.606 0.96
9.5 0.395 0.623

0.986

10

0.405 0.639 1.012
11 0.425 0.67

1.061

12

0.443 0.7 1.109
13 0.462 0.728

1.154

14

0.479 0.756 1.197
15 0.496 0.782

1.239

16

0.512 0.808 1.28
17 0.528 0.833

1.319

18

0.543 0.857 1.358
19 0.558 0.88

1.395