306A Pipe Joining and Fitting Methods 2

Question 1

When joining ABS or PVC drain pipe with solvent cement, what motion is used when inserting the pipe into the socket?

Accepted Answer

Give the pipe a quick quarter-turn while pushing to full depth, then hold without rotation

Answer

Rotate the pipe continuously while pushing it in to spread the cement evenly

Answer

Push the pipe straight in with no rotation and hold for 30 seconds

Answer

Rotate the pipe one full clockwise turn before pushing to socket depth

Question 2

What is the correct sequence of operations when cutting and threading steel pipe on a power threading machine?

Accepted Answer

Cut to length, ream the inside, thread, apply sealant, then assemble

Answer

Thread the pipe first, then cut to length, ream, and apply sealant

Answer

Cut to length, thread, then ream the inside, apply sealant

Answer

Ream first, cut to length, thread, then apply sealant

Question 3

What is the approximate pressure rating of 1-inch Schedule 40 PVC pipe at 23°C for cold water service?

Accepted Answer

Approximately 690 kPa (100 psi), with the rating decreasing as temperature rises

Answer

Approximately 1,380 kPa (200 psi) regardless of temperature

Answer

Only 345 kPa (50 psi) for any PVC installation

Answer

PVC Schedule 40 has no pressure rating and cannot be used for supply lines

Question 4

When soldering a copper fitting, where should the heat from the torch primarily be directed?

Accepted Answer

To the fitting body, allowing capillary action to draw solder fully into the joint

Answer

To the solder wire directly, melting it so it drips into the joint

Answer

To both the pipe and fitting equally and simultaneously

Answer

To the pipe only, well away from the fitting body

Question 5

In which direction should PTFE thread tape be wound around male pipe threads before making a connection?

Accepted Answer

Clockwise when viewed from the threaded pipe end, in the direction of thread engagement

Answer

Counter-clockwise when viewed from the threaded pipe end

Answer

Direction is irrelevant as long as the tape is applied tightly

Answer

PTFE tape must never be used — only liquid pipe sealant is acceptable on threaded joints

Question 6

What is the minimum cure time before a solvent-cemented CPVC hot water line may be pressure tested in warm conditions (above 15°C)?

Accepted Answer

Follow manufacturer specifications — typically a minimum of 1 hour before low-pressure test and 24 hours before full system pressure

Answer

5 minutes — CPVC solvent cement achieves full strength almost instantly

Answer

72 hours minimum regardless of temperature or pipe size

Answer

No cure time required; CPVC joints may be pressure tested immediately after assembly

Question 7

Which type of coupling allows pipes of different outer diameters or materials to be joined in a drain system without threading or solvent cement?

Accepted Answer

A banded rubber (Mission/no-hub-type) coupling with stainless steel clamp bands

Answer

A standard PVC socket coupling with solvent cement

Answer

A grooved (Victaulic-type) coupling that requires precision-machined grooves on both pipes

Answer

A compression fitting with a brass ferrule and compression nut