Product Overview

F-24388-1 © Copyright 2006 TAC All Rights Reserved. 7
For example, if a valve is controlling 200°F water at an inlet pressure of 18 psig, the
maximum pressure drop allowable would be:
Pm = 0.5 [(18 + 14.7) – 11.53] = 10.6 psi
(Vapor pressure of 200°F water is 11.53 psia.)
If the pressure drop for this valve is less than 10.6 psi, cavitation should not be a problem.
Systems where cavitation is shown to be a problem can sometimes be redesigned to provide
lower inlet velocities.
Table-7 Vapor Pressure of Water Table.
Additional Valve
Sizing Information
For additional valve sizing information, see:
CA-28 Control Valve Sizing, F-13755
Valve Selection Chart Water, F-11080
Valve Selection Chart Steam, F-11366
Valve Sizing Slide Rule, TOOL-150
Water
Temp.
(°F)
Vapor
Pressure
(psia)
Water
Temp.
(°F)
Vapor
Pressure
(psia)
Water
Temp.
(°F)
Vapor
Pressure
(psia)
Water
Temp.
(°F)
Vapor
Pressure
(psia)
40 0.12 90 0.70 140 2.89 190 9.34
50 0.18 100 0.95 150 3.72 200 11.53
60 0.26 110 1.28 160 4.74 210 14.12
70 0.36 120 1.69 170 5.99 220 17.19
80 0.51 130 2.22 180 7.51 230 20.78