Valves, Fittings, and Pipe Materials Flashcards

A reducing tee is used in a piping system to:

Answer: Branch off a smaller pipe from a larger main line

A reducing tee has a branch outlet smaller than the main run, allowing a smaller pipe to tap into a larger header.

Which type of pipe joint is most suitable for underground gas distribution piping?

Answer: Butt weld

Butt welding creates a continuous, leak-tight joint ideal for underground gas piping where access for maintenance is limited.

Ductile iron pipe differs from gray cast iron pipe primarily in that it:

Answer: Has greater tensile strength and impact resistance

Ductile iron's microstructure (spheroidal graphite) gives it far greater tensile strength and toughness than brittle gray cast iron.

A pressure relief valve on a steam boiler is set to open at:

Answer: The maximum allowable working pressure (MAWP)

Relief valves are set to open at or below the MAWP stamped on the boiler to prevent overpressure damage.

Which fitting is used to close the end of a pipe with internal threads?

Answer: Plug

A plug has external threads and is installed into the internally threaded end of a pipe or fitting to seal it.

CPVC pipe is preferred over standard PVC for hot water distribution because it:

Answer: Can handle higher temperatures up to approximately 200°F

Chlorinated PVC (CPVC) is rated for continuous service up to approximately 200°F, making it suitable for domestic hot water systems.

A union fitting is installed in a piping system primarily to:

Answer: Allow removal of equipment or pipe sections without cutting

A union's three-piece design allows the line to be disconnected and reconnected without disturbing adjacent piping.