Journeyman Plumbers Isometric Drawings and Math Questions and Answers

Question 1

A plumber is installing a drain line with a simple horizontal offset of 24 inches using 45-degree fittings. What is the required center-to-center length of the travel piece?

Accepted Answer

33.94 inches

Answer

24.00 inches

Answer

48.00 inches

Answer

16.97 inches

Question 2

An isometric drawing shows a rolling offset where a vent pipe rises 15 inches vertically and offsets 20 inches horizontally, using 45-degree fittings. What is the center-to-center length of the travel pipe required for this offset?

Accepted Answer

35.35 inches

Answer

25.00 inches

Answer

49.49 inches

Answer

28.28 inches

Question 3

A journeyman plumber is installing a 3-inch horizontal sanitary drain that is 42 feet long. If the required minimum slope is 1/4 inch per foot, what is the total fall of the pipe over its entire length?

Accepted Answer

10.5 inches

Answer

8.5 inches

Answer

14 inches

Answer

21 inches

Question 4

When interpreting a plumbing isometric drawing, a vertical pipe run is always represented by which of the following?

Accepted Answer

A true vertical line on the page.

Answer

A line drawn at a 45-degree angle.

Answer

A true horizontal line on the page.

Answer

A circle with a dot in the center.

Question 5

A plumber needs to cut a piece of copper pipe to connect two 90-degree wrought copper elbows. The center-to-center measurement between where the fittings will be is 36 inches. The fitting allowance (take-off) for each elbow is 3/4 inch. What is the required end-to-end cut length of the pipe?

Accepted Answer

34 1/2 inches

Answer

37 1/2 inches

Answer

36 inches

Answer

35 1/4 inches

Question 6

In a plumbing isometric drawing, a vertical drain stack changes to a horizontal run. Which of the following fittings is typically used for this transition to ensure proper flow?

Accepted Answer

A long sweep 90-degree elbow or a combination wye and 1/8 bend

Answer

A sanitary tee laid on its back

Answer

A vent tee

Answer

A standard short-radius 90-degree elbow

A plumber is installing a drain line with a simple horizontal offset of 24 inches using 45-degree fittings.What is the required center-to-center length of the travel piece?

A plumber is installing a drain line with a simple horizontal offset of 24 inches using 45-degree fittings.
What is the required center-to-center length of the travel piece?