Graco XM PFP Instructions - Parts Manual page 14

Operation
Table 2: Hose Selection by Pressure Drop
Pressure drop in psi
Hose ID (per 50 ft section per 1,000
(in.) cps at 1 gal/min.)
1/8
3/16
1/4
3/8
1/2
5/8
3/4
Reference Formula
Total Pressure Drop = P x V x L x F
Key:
P= Pressure drop from chart
V = Viscosity in centipoise /1000
L= Length of hose in feet / 50
F= Flow rate in gallons per minute
Example #1: What is the pressure loss of a 2,000 cps
material through 150 ft of 3/8 in. ID hose at 0.75 gpm?
690 psi (from chart) x 2 (2,000 cps /1,000) x 3 (150 ft / 3)
x 0.75 (gpm) = 3105 psi loss
This is a lot of pressure loss before reaching the spray
gun. Continue to Example #2 which examines the same
situation but with a 1/2 in. ID hose.
14
(per 15.24 meter section per
55,910
11,044
3,494
690
218
89
43
Pressure Drop in bar
1,000 cps at 1 liter/min.)
1,018
201
64
13
4
1.62
0.78
Example #2: What is the pressure loss of a 2,000 cps
material through 150 ft of 1/2 in. ID hose at 0.75 gpm?
218 psi (from chart) x 2 (2,000 cps /1,000) x 3 (150 ft / 3)
x 0.75 (gpm) = 981 psi loss
3A2988C