6
Watts Water Technologies, Inc.
The cavitation diagram shows three operating zones of the pressure reducing valve plotted against the upstream and downstream
pressures, namely:
C zone: normal duty, no cavitation
B zone: medium duty, risk of cavitation
A zone: heavy duty, the pressure reducing valve shows cavitation.
Continuous operation in the red cavitation zone could cause rapid damage of the internal parts. If the pressure reducing valve is to
operate in the red zone, contact the Technical Department of Watts Industries Italia.
20
18
16
14
12
10
8
6
4
2
0
0
1
2
3
Downstream pressure (bar)
4
5
6
7
A
B
C
Inlet pressure (bar)
A Cavitation Zone B Transition Zone C Work Zone
Flow rate
Speed (m/s)
DN
15
30
20
10
8
1
0,6
0,4
0,2
0,1
0,1
0,2
0,4 0,6 0,8
2
4
6
10
20
60
200
1000
1
8
40
100
400 600
10
50
100
1000
10000
5
500
5000
6
4
2
0,8
Acqua
Aria
m
3
/h
l/min
DN
20
DN
25
DN
32
DN
40
DN
50
Cavitation
Cavitation diagram
Charts
DRV-DRVN
