Pipe Systems and Materials Flashcards
7 cards from real STEAMFITTER practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Pipe Systems and Materials flashcards as text
What is the function of a reducing coupling in a piping system?
Answer: To connect pipes of two different diameters in a straight run
A reducing coupling joins two pipes of different sizes in line, allowing a transition from a larger to a smaller (or smaller to larger) pipe diameter.
What type of pipe thread standard is most commonly specified for threaded connections in U.S. steam and water piping systems?
Answer: NPT (National Pipe Taper)
NPT (National Pipe Taper) is the US standard for threaded pipe connections; the tapered threads create a pressure-tight seal when engaged and assembled with thread sealant.
A concentric reducer is different from an eccentric reducer in that a concentric reducer:
Answer: Keeps the pipe centerlines aligned on the same axis
A concentric reducer maintains the same centerline for both pipes, while an eccentric reducer offsets one side flat, which is preferred on horizontal lines to prevent air or condensate pocketing.
Which type of valve is best suited for throttling or regulating flow in a steam piping system?
Answer: Globe valve
Globe valves are specifically designed for throttling because their plug-and-seat design provides fine flow control; gate and ball valves are intended for full-open or full-closed service only.
What is the primary advantage of a flanged connection compared to a threaded connection in a large-diameter steam line?
Answer: Flanged connections can be disassembled without cutting or unthreading the pipe
Flanged connections allow piping to be disassembled by unbolting the flanges, making them ideal for large-diameter pipe and equipment connections that require periodic maintenance.
What type of joint is formed when a copper fitting is heated and a filler metal (solder) is drawn into the gap by capillary action?
Answer: Sweat (soldered) joint
A sweat joint (also called a soldered or brazed joint) uses heat and capillary action to draw solder or brazing alloy into the annular space between the pipe and fitting, forming a pressure-tight bond.
In the metric piping system used internationally, what does the designation DN (Diameter Nominal) represent?
Answer: The approximate nominal pipe diameter in millimeters used as a reference size
DN (Diameter Nominal) is a dimensionless designator that approximates the nominal pipe size in millimeters and corresponds to NPS sizes — e.g., DN 25 ≈ NPS 1 inch.