The term "open-end discharge" refers
to a hose which empties a fluid into the atmosphere.
Even though one end is open, the pressure is not low
throughout the hose. The inlet end pressure is equal
to that in the line to which the hose is connected
unless the flow rate is so low that the hose is not
completely filled. The pressure along the hose length
drops from a maximum at the inlet to zero at the outlet
and the pressure at any given point along the length
is nearly proportional to the distance from the hose
inlet. The following table shows the flow in gallons
per minute in open-end discharge service.
|
Open-End Flow (GPM) |
|
Pressure at
inlet, psi |
Hose length,
Feet |
|
25 |
50 |
75 |
100 |
125 |
150 |
200 |
300 |
|
1/2" hose |
30
40
50
60
70
80
90
100
125 |
10.4
12.1
13.8
15.2
16.6
18.0
19.0
20.1
22.8 |
6.2
8.5
9.4
10.4
11.2
12.1
13.0
13.8
15.5 |
5.6
6.2
7.5
8.5
9.0
9.8
10.4
11.0
12.5 |
4.8
5.6
6.4
7.1
7.8
8.5
8.8
9.4
10.5 |
4.3
5.0
5.6
6.2
6.8
7.3
7.7
8.5
9.4 |
3.8
4.5
5.1
5.6
6.2
6.6
7.1
7.5
8.5 |
3.3
3.8
4.0
4.9
5.3
5.6
6.0
6.4
7.2 |
2.6
3.2
3.5
3.8
4.2
4.5
4.8
4.9
5.8 |
|
5/8" hose |
30
40
50
60
70
80
90
100
125 |
18.1
21.4
23.9
26.5
27.5
30.6
32.5
34.5
39.0 |
12.5 14.8
16.5
18.1
20.0
21.4
22.5
23.9
27.0 |
10.3
12.5
13.2
14.8
16.0
16.8
18.1
19.0
21.5 |
8.7
10.3
11.4
12.5
13.7
14.8
15.5
16.6
18.5 |
7.7
9.0
10.3
11.2
12.0
13.0
14.0
14.8
16.6 |
7.0
8.3
9.2
10.3
11.0
11.8
12.5
13.2
15.0 |
6.0
7.0
7.9
8.7
10.0
10.3
10.5
11.4
12.9 |
4.9
5.7
6.3
7.0
7.6
8.3
8.7
9.2
10.5 |
|
3/4" hose |
30
40
50
60
70
80
90
100
125 |
31.0
36.0
41.0
45.5
49.5
53.0
56.2
60.0
68.0 |
21.3
25.0
28.0
31.0
34.0
36.0
39.0
41.0
46.0 |
17.2
20.0
22.5
25.0
27.2
29.1
31.0
33.0
37.5 |
14.8
17.2
19.2
21.3
23.5
25.0
27.0
28.0
32.0 |
13.0
15.2
17.2
19.0
21.0
22.0
23.8
25.0
23.0 |
11.8
13.8
15.5
17.2
18.8
20.0
21.3
22.6
25.8 |
10.2
11.8
13.2
14.8
17.1
17.2
18.2
19.2
21.8 |
8.2
9.4
10.7
11.8
12.8
13.8
14.8
15.5
17.5 |
|
1" hose |
30
40
50
60
70
80
90
100
125 |
68.0
79.0
89.0
100.0
-
-
-
-
- |
46.2
54.4
62.0
68.0
74.0
79.0
84.0
89.0
101.0 |
37.5
44.0
49.0
54.4
59.0
63.0
68.0
71.0
80.0 |
32.0
37.5
42.0
46.2
51.0
54.4
58.0
62.0
68.0 |
28.5
33.0
37.5
41.8
45.0
48.0
51.8
54.4
62.0 |
25.8
30.0
34.0
37.5
40.8
43.0
46.2
49.0
55.8 |
22.0
25.8
29.0
32.0
37.3
37.5
40.0
42.0
47.8 |
17.8
20.8
23.3
25.8
28.0
30.0
32.0
34.0
38.0 |
|
1 1/4" hose |
50
75
100
150 |
-
-
-
- |
110.0
130.0
150.0
- |
85.0
110.0
125.0
150.0 |
72.0
90.0
110.0
130.0 |
56.0
80.0
92.0
120.0 |
58.0
73.0
85.0
110.0 |
50.0
64.0
73.0
90.0 |
42.0
52.0
58.0
67.0 |
|
13/8" hose |
50
75
100
150 |
-
-
-
- |
140.0
170.0
205.0
- |
115.0
140.0
160.0
205.0 |
96.0
125.0
140.0
170.0 |
85.0
110.0
125.0
155.0 |
75.0
96.0
110.0
140.0 |
65.0
84.0
96.0
125.0 |
54.0
67.0
75.0
97.0 |
|
11/2" hose |
50
75
100
150 |
-
-
-
- |
180.0
230.0
260.0
- |
150.0
180.0
220.0
260.0 |
130.0
160.0
180.0
230.0 |
120.0
145.0
170.0
205.00 |
105.0
130.0
150.0
180.0 |
90.0
120.0
130.0
160.0 |
74.0
90.0
105.0
130 |
|
2" hose |
50
75
100
150 |
-
-
-
- |
380.0
480.0
550.0
- |
310.0
380.0
450.0
550.0 |
270.0
330.0
380.0
480.0 |
240.0
290.0
350.0
425.0 |
210.0
270.0
310.0
380.0 |
180.0
230.0
260.0
330.0 |
150.0
180.0
215.0
265.0 |