Document RJxzXL8ZO1YDYJGBQmnOY3jxB
HEATING VENTILATING AIR CONDITIONING GUIDE 1943
Table 9. Pressure Losses in Dichlorodifluoromethane Suction Refrigerant Lines
Copper Pipe Actual O.D.
Inches
Capacity ' Btu per Hour
Pressure Drop in Pounds per Square Inch per 100 Fra Refrigerant Temperature Dbg F
-10
0
10 20 30 40 50
2.000 4,000 6,000 8,000 10,000
0.3 0.3 0.2 0.2 0.2 0.1 0.1 1.3 1.0 0.8 0.7 0.6 0.5 0.4 2.8 2.2 1.8 .15 1.2 1.0 0.9 4.8 3.8 3.1 2.6 ' 2.1 1.8 1.5 7.4 5.8 4,8 3.9 3.3 2.8 2.3
12,000 14,000 16,000
18.000 20,000
10.5 8.4 6.8 5.6 4.7; 4.0
14.0
11.0
9.1
7.6
6.4
5.4
14.5
12.0
9.8
8.3
7.0
15.0 12.3 10.4
8.7
15.0 12.7 10.7
3.3 4.5 5.8 7.2 8.9
7,000 10,000 15,000
20,000 25,000
0.4 . . 0.3 0.3 0.2 0.2 0.2 0.1
1.0 0.7 0.5 0.5 0.4 0.3 0.3 1.9 1.5 1.2 1.0 0.8 0.7 0.6 3.3 2.6 2.1 1.7 1.4 1.2 1.0 5.0 4.0 3.2 2.7 2.2 1.9 1.6
35,000 45,000 60.000
70,000
9.7 15.8
7.7 12.6
6.2 10.0
5.1 . 8.4 14.8
4.3 7.0 12.2
3.6 5.9
10.2
14.0
3.0
4.9 8.6
11.7
10,000
0.3
0.2
0.2
0.2
0.1 .
0.1
0.1
15,000
0.7 0.5 0.4 0.3 0.3 0.2 0.2
20.000
1.2 0.9 ' 0.7 0.6 0.5 0.4 0.4
30,000
2.6 2.1 1.6 1.3 1.1 0.9 0.8
1H
40,000
416 3.6 2.8 2.3 1.9 1.6 1.4
50.000 60,000 80,000
IpO.OOO
7.0 10.0
5.5 7.8 14.0
4.4 6.2
11.0
3.5 5.0
8.7.
13.5.
2.9 4.2
7.3
11.3
2.5
3.5 , 6.2
9.5,
2.1
3.0 5.2
8.2
30,000 40,000 50,000
60,000 70.000
1.6 1.3 . 1.0 0.8 0.7 0.6 0.5 2.7 2.1 1.7 1.4 1.1 0.9 0.8 4.2 3.2 2.5 2.1 1.7 1.4 1.2
6.1 4.5 3.6 2.9 2.4 2.0- 1.7 8.7 6.3 ' 4.8 3.8 3.1 2.6 2.2
80,000
90,000 100.000 120.000
140.000
8.4 6.3 4.9 4.0 3.3 2.8
8.0
6.2
4.9
4.1 .
3.5
10.0 7.6 6.1 5.0 4.2
8.6 7.0 5.9
9.5 7.9
50,000
0.7 0.5 0.4 0.3 . 0.3 0.2 0.2
100,000
2.6 1.8 1.4 1.1 0.9 0.8 0.7
150.000
5.6 3.9 3.0 2.4 2.0 1.6 1.4
200.000
9.8
6.7 '
5.2
4.1
3.4
2.8
2.4
2M
250,000
14.8
10.3
8.0'
6.3
5.1
4.2
3.6
300,000
14.5
11.3 . . 9.0
7.2
6.0
5.0
350,000
19.5 . 15.3
12.0
9.7
7.8
6.7
400,000
19.6 15.3 12.5 10.0
8.5
aLength of tubing includes the average number of fittings.
with the cooling coils. Another common and efficient method of cooling
spray water is to use a Baudelot type of heat absorber where the water
flows over direct expansion coils at a rate sufficiently high to give efficient
heat transfer f^om water to refrigerant;
-
Another type of spray water cooler is the shell, and tube heat exchanger in which the refrigerant is expanded into a shell: enclosing the tubes through which the water flows. The velocity of the-water in the tubes affects the rate of heat transfer, and as the`refrigerant is in the shell-com-
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CHAPTER 25. REFRIGERATION
Table 9. Pressure Losses in Dichlorodifluoromethane Suction Refrigerant Lines (Concluded)
Copper Pipe Actual O.D.
Inches
Capacity Btu per Hour
Pressure Drop in Pounds per Square Inch per 100 Ft Refrigerant Temperature Deg F
-10
0
. 10
.20
. 30
40
50
50.000 100,000 150.000 200,000
0.2
0.2
0.1
0.1
0.1
0.1
0.1
0.7 0.6 0.5 0.4 0.3 0.2 0.2
1.6 1.2 1.0 0.8 0.6 0.5 0.4
2.8 2.1 1.7 1.4 1.1 0.9 0.7
250.000
4.3 3.4 , 2.6 2.1 1.7 1.3 1.1
2M
300.000
6.1 4.5 3.7 3.0 2.4 1.9 .1.5
350,000 8.2 6.0 5.0 4.0 3.2 2.5 2.0
400,000
7.8 6.5 5.1 4.2 3.3 2.7
450,000 500,000 550.000
600.000
7.7 6.4 5.3 4.0 3.5 7.8 6.4 5.0 4.2
7.7 6.2 5.1 J 7.4- 6.2
200,000
1.2 1.0 0.8 0.6 0.5 0.4 0.4
300.000
2.6 2.0 1.6 1.3 1.0 0.8 0.7
400.000
4.5 3.4 2.6 2.1 1.7 1.4 1.3
500,000
7.3 5.4 . 4.1 3.3 2.7 2.2 1.9
3K 600,000
8.1 6.0 4.7 3.8 3.1 2.7
700,000 800WK)
900.000
1,000.000
^
8.4 6.5 5.2 4.2 3.5 8.6 6.8 5.5 4.6 8.7 7.0 5.9 8.9 7.3
m
300,000 400,000 500,000 600,000
700,000 800,000 900,000 1,000,000
1,100.000 1,200,000 1,300,000' 1,400,000
1.2 0.9 0.7 2.0 1.6 1.3 3.2 2.5 1.9 4.6 3.6 2.8
6.4 4.9 3.8 8.7' 6.4 4.9
8.2 6.2 7.7
9.4
0.6 1.0 1.6 2.2
3.0 3.9 4.9 6.1
7.3 . 8.7
0.5 0.8 1.3 1.8
2.5 3.2 3.9 4.9 '
5.8 6.9 8.0 9.3
0.4 0.7 1.0 1.5
2.0 2.5 3.2 4.0
4.8 5.6 6.6 ' . 7.6 .
0.3 0.6. 0.9 1.3
1.7 2.2 2.7 3.3
4.0 4.8 5.6 . 6.4
400,000 * 600,000
800,000 1,000,600 1,200,000
1.400.000 1,600,000 1,800.000 2,000,000 2,200.000
.
1.0 2.4 4.1 6.6
10.0
0.8 1.8 3.1 4.8 7.1
10.0
0.6 1.4 2.4 3.7 5.4
7.5 10.0
0.4 1.1 2.0 3.0 4.f
5.9 7.7 10.0
0.4 0.9 1.6 2.5* 3.5
4.8 6.2 . 7.9 9.7
0.3 . 0.7 1.3 2.0 2.9 -
3.9 5.1
6.4 7.9 9.5
0.3 0.6 1.1 1.6 .2.4
3.3 4.2 5.3 6.6 7.9
aLength of tubing includes the average number of fittings.
pletely surrounding the tubes at all times, good contact and a high rate of heat transfer are insured.' The disadvantage of such a system is that with the falling off of load on the compressor the suction temperature or the temperature in the evaporator.drops and there is.a possibility of freezing the water in the tubes, which, of course, might split, the tubes and.allow the refrigerant to escape into the water passage. This danger can be eliminated by automatic safety devices.
Another system of cooling;spray water is, to submerge coils in the spray
495
