72 
BULLETIN 376, U. S. DEPARTMENT OF AGEICULTUEE. 
CAPACITY OF WOOD-STAVE PIPE COMPARED WITH THAT OF CAST- 
IRON AND RIVETED STEEL. 
Table 8 gives the relative carrying capacities of wood, steel, and 
cast-iron pipes. The table is based on velocities of about 1, 3, and 7 
feet per second in the steel and cast-iron pipes of diameters ranging 
from 4 to 144 inches. For a given velocity the loss of head for new 
cast-iron, new riveted steel, 10-year-old cast-iron, 20-year-old cast- 
iron, and 10-year-old-riveted steel is based on values of C w in the 
Wffliams-Hazen formula (No. 8, p. 6) of 130, 110, 110, 100 and 100, 
respectively, these conservative values being recommended by 
Williams and Hazen. 
Table 8. — Relative capacity, in per cent, of ivood-stave pipe, compared with new cast 
iron, new riveted, 10-year-old cast iron, 20-year-old cast iron, and 10-year-old riveted 
steel or iron pipe; based on Williams and Hazen recommendation for values of C, in 
their formula, of 130 for new cast iron, 110 for new riveted and 10-year-old cast iron, 
and 100 for 20-year-old cast iron and 10-year-old riveted steel or iron pipe. 
Cast-iron and riveted pipes. 
Wood-stave pipes. 
Per cent of velocity in 
wood pipe over that 
Diam- 
eter. 
Velocity 
Loss of head for velocity. (H) 
Velocities correspond- 
ing to losses in col- 
in metal pipe (column 
2), corresponding to 
columns 6, 7, 8, re- 
spectively. 
per 
second. 
C w =130. 
c w =no. 
C w =100. 
umns 3, 4, 5, 
tively. 
respec- 
Inches. 
Feet. 
Feet. 
Feet. 
Feet. 
Feet. 
Feet. 
Feet. 
4 
4 
4 
12 
1.02 
3.06 
6.64 
.99 
1.380 
10. 500 
44.000 
.360 
2.230 
17. 100 
72.000 
.580 
0.94 
2.90 
6.50 
.92 
'"'i.'os' 
1.24 
3.90 
8.51 
1.20 
-7.8 
-5.2 
-2.1 
-7.1 
+ 9 
+22 
+26 
+28 
+20 
6-480" 
12 
2.96 
2.730 
3.710 
4.430 
2.83 
3.33 
3.70 
-4.4 
+ 12 
+25 
12 
6.89 
13.200 
17. 900 
21.300 
6.80 
8.00 
8.80 
-1.3 
+16 
+28 
36 
1.09 
.121 
.164 
.196 
1.02 
1.25 
1.34 
-6.4 
+15 
+ 23 
36 
3.06 
.810 
1.110 
1.320 
2.90 
3.50 
3.80 
-5.2 
+14 
+ 24 
36 
7.00 
3.740 
5.100 
6.100 
6.90 
8.10 
9.00 
-1.4 
+16 
+29 
72 
.98 
.044 
.060 
.072 
.92 
1.10 
1.20 
-6.1 
+12 
+22 
72 
3.01 
.349 
.476 
.570 
2.90 
3.50 
3.80 
-3.6 
+16 
+24 
72 
7.11 
1.720 
2.340 
2.790 
7.00 
8.30 
9.10 
-1.5 
+17 
+28 
108 
1.10 
.034 
.046 
.055 
1.00 
1.20 
1.35 
-9.1 
+ 11 
+23 
108 
3.14 
.237 
.321 
.382 
3.00 
3.60 
4.00 
-4.4 
+15 
+27 
108 
6.92 
1.020 
1.380 
1.650 
6.90 
8.00 
9.00 
- .3 
+16 
+30 
144. 
1.06 
.023 
.031 
.037 
1.00 
1.20 
1.35 
—5.7 
+13 
+21 
144 
3.01 
.156 
.211 
.252 
2.90 
3.40 
3.80 
-3.7 
+13 
+26 
144 
7.07 
.760 
1.030 
1.230 
7.00 
8.30 
9.10 
-1.0 
+17 
+29 
For the same sized pipe and the various losses of head the corre- 
sponding velocities in wood-stave pipe (as shown by the new formula) 
are compared with the velocities in the metal pipes. This comparison 
is on a percentage basis, with the velocity of the metal pipe as the 
base. As an example: The loss of head in a new cast-iron pipe 
(C w = 130), 12 inches in diameter, for a velocity of 2.96 feet per 
second, is 2.73 feet per 1,000 feet of pipe. For the same velocity in 
new riveted steel or 10-year-old cast iron (C w = 110) the loss of head 
in a 12-inch pipe is 3.71 feet. For the same velocity in 10-year-old 
riveted steel or 20-year-old cast iron (C w =100) the loss of head is 
4.43 feet. 
