Practice Test Geeks(SPED) Society of Piping Engineers and Designers Certification Practice Test
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Valve & Fitting Selection Flashcards

7 cards from real SPED practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Valve & Fitting Selection flashcards as text

  1. A designer must select a valve for oxygen service. Which material combination should be strictly avoided?

    Answer: Carbon steel body with petroleum-based lubricant

    Petroleum-based lubricants and greases ignite violently in high-pressure oxygen, making them strictly prohibited; only oxygen-compatible lubricants and materials may be used.

  2. What is the primary difference between a globe valve and a needle valve?

    Answer: Needle valves have a tapered, pointed disc providing fine flow metering; globe valves use a plug or disc for general throttling

    Needle valves incorporate a long, tapered cone that allows very fine, precise flow adjustment, while globe valves use a broader disc or plug for general throttling service.

  3. Which ASME standard governs factory-made wrought buttwelding fittings (elbows, tees, reducers) for NPS 1/2 through NPS 48?

    Answer: ASME B16.9

    ASME B16.9 covers factory-made wrought steel buttwelding fittings including dimensions, tolerances, and pressure ratings for NPS 1/2 through NPS 48.

  4. An eccentric reducer is installed with the flat side up in a horizontal liquid pipeline. What is the primary reason for this orientation?

    Answer: To prevent air pocket accumulation at the top of the fitting

    With the flat side up, the top of the pipe is level through the reducer transition, preventing trapped air pockets that would impair pump performance or cause vapor lock.

  5. Which valve trim material combination is suitable for service with dilute hydrofluoric acid (HF acid)?

    Answer: Monel (Alloy 400) body with Monel trim

    Monel (Alloy 400) exhibits excellent resistance to dilute and concentrated hydrofluoric acid, making it the preferred material for HF acid piping and valve components.

  6. What is the purpose of a sample valve or instrument root valve in process piping?

    Answer: To regulate flow to analytical instruments or sampling points and allow isolation for maintenance

    Root valves provide the primary isolation between the process piping and the instrument or sampling connection, enabling safe removal of instruments without process shutdown.

  7. When a piping specification calls for ASME B16.11 Class 3000 socket weld fittings, what nominal pipe schedule do these fittings generally correspond to?

    Answer: Schedule 80

    ASME B16.11 Class 3000 socket weld fittings are dimensioned to match Schedule 80 (XS) pipe wall thickness for NPS 1/2 through NPS 2.