math

Question 1

A horizontal like is 50ft long with a hanger pat each end.how many additional hangers will be required if the spacing between hanger is3ft

Answer 1

50/3= 16.7
roundup to 17
+ 1
18 is the answer

Look at pipe as if it were one long piece of pipe.

Take the total length of all the pipe and divide it by the maximum horizontal spacing of supports in Table 2.3.4.5.
Take the number from 2 and round up and add one.

Example: 6” pipe, 75 ft long. 75ft is 22.87 m. 22.87 m divide by 3.75 m (Table 2.3.4.5) = 6.09. Round up to 7 plus one = 8 hangers.

Question 2

A pipe is 145 ft long is graded at a rate of 2 1/2%. what is the fall

Answer 2

2 1/2/100= 0.025.

0.025 x 145 ft= 3.625 fall

answer shows 30.25

Question 3

A pipe is 225 ft long and is dropped 16 inches. what is the rate of fall in percent

Answer 3

16/12= 1.33 ft

1.33/225 = 0.0059

0.0059 x 100= 0.59%

Question 4

how much expansion would occur on a 300 ft steel pipe installed at 49 f and operating at 190 f (co efficient of .0000061

Answer 4

the original length of pipe= 300 ft
co efficient= 0.0000061
temperature change= (180-49)=131 f

0.0000061 x 300 x 131= 0.23973

0.23973 x 12 = 2.88 inch of expansion of steel

Question 5

what is the total fall on a 227 foot piece of pipe which grades down 1/4 per foot

Answer 5

227 x 0.25= 56.75 inches

Question 6

what is the total fall on a 29 meter piece of pipe which grades a 2”

Answer 6

29 m x 0.02=.58 m
.58 m / 3.28= 1.9 ft

Question 7

total fall on a 456 foot piece pf pipe which is graded at 1/50

Answer 7

456 x 0.02– 9.12

Question 8

Calculate the grade as a ratio given that a piece of pipe fall 0.42m over a distance of 300m

Answer 8

300 / 0.42 = 714.28

Question 9

What would the grade be on a pipe which falls 5 3/8 inches in 72ft in percentage

Answer 9

5.375/864= .0062

0.0062 x 100= 62%

Question 10

If a print is drawn at a scale of 1/4 per foot would the actual length of the pipe be if it was drawn 9 1/2 inches On on the drawing

Answer 10

2 feet 9 1/2= 24 inches
9 1/2= 9.5 inches

24=9.5= 33.5 inches

33.5 / 0.25= 134 ft

Question 11

What is the expansion on a 234 f piece of steel pipe given that the temperature of the liquid in the pipe goes from 20 c to 70 C and co efficient is 0.0000067

Answer 11

0.0000067 x 234 x 50 = 0.078

Question 12

a 6-inch (150mm) cast iron soil pipe with a 1/4 (6mm) wall thickness requires a sleeve. what is the minimum inside diameter of the sleeve required

Answer 12

6 + 1/4 + 1/4= 6 1/2