GPT Material Selection & Properties 3

Question 1

Which joining method is approved for steel gas pipe connections in concealed locations?

Accepted Answer

Welded joints

Answer

Welded joints are the approved method for concealed steel gas pipe because they create a permanent, leak-free connection without mechanical components that can loosen.

Question 2

A copper tube marked 'ACR' is found on a job site. Can it be used for natural gas service?

Accepted Answer

No, ACR tubing is dehydrated for refrigerants only and not rated for gas

Answer

ACR (Air Conditioning & Refrigeration) copper tubing is pre-cleaned and sealed for refrigerants and is not approved for gas service; only Type K or L labeled for gas use is acceptable.

Question 3

What minimum pipe wall thickness in inches is required for 2-inch Schedule 40 steel pipe?

Accepted Answer

0.154 inches

Answer

2-inch Schedule 40 steel pipe has a nominal wall thickness of 0.154 inches per ASME dimensional standards.

Question 4

Which gas piping material requires bonding to the electrical grounding system per NFPA 54?

Accepted Answer

CSST

Answer

CSST requires bonding to the electrical grounding system because its thin corrugated walls can be punctured by arc damage from lightning-induced surges.

Question 5

A gas pipe runs through an exterior wall in a cold climate. Which material concern is most critical?

Accepted Answer

Thermal expansion cracking of PE pipe

Answer

PE pipe becomes brittle at low temperatures and is not approved for above-ground use, making thermal cracking the primary concern if misused.

(GPT) Gas Pipe Technician Certification Practice Test

(GPT) Gas Pipe Technician Certification Practice Test

GPT Material Selection & Properties 3