172-65207MA-08 (SR-3/SR-8) 8 Oct 2020
16
Piping Installation 4: Water Inlet and Outlet Piping
Other cautions
Connect the cold water piping to the cold water inlet, and connect return piping from
the hot water outlet to an area where the hot water can be utilized. To secure an
adequate amount of cold feed water, make sure that the hydraulic pressure
differential (pressure differential between inlet and outlet) is at least equal to the
values in the following table. However, the water pressure must not exceed the
maximum operating water pressure of 1.0 MPaG (150 psig).
Required Cold
Water (t/h)
1
2
3
4
5
6
8
10
12
14
Hydraulic
Pressure
Differential
(MPa)
SR-3
0.03
0.11
0.23
0.40
0.62
—
—
—
—
—
SR-8
—
—
0.03
0.05
0.07
0.10
0.17
0.27
0.38
0.60
(1 MPa = 10.197 kg/cm
2
)
Required Cold
Water (lb/h)
2000 4000 6000 8000 10000 12000 16000 20000 24000 28000
Hydraulic
Pressure
Differential
(psi)
SR-3
3.6
12.9
27.8
48.2
74.0
—
—
—
—
—
SR-8
—
—
3.4
5.8
8.7
12.3
21.2
32.4
45.9
61.8
The diameter of the pipe before and after the SR varies with the required amount of
cold water, and it should be sized so that the velocity of cold water is 2 to 3 m/sec (6.6
to 9.8 ft/sec). Suggested diameters for the cold water inlet and hot water outlet piping
are as follows:
Water Flow (t/h)
1
2
3
4
5
6
7
8
10
Pipe Diameter (mm)
15
15
20
25
25
32
32
32
40
Water Flow (lb/h)
2000
4000
6000
8000 10000 12000 14000 16000 20000
Pipe Diameter (in)
1
/
2
1
/
2
3
/
4
1
1
1
1
/
4
1
1
/
4
1
1
/
4
1
1
/
2
