PIC Quiz (chap l control valve Tutorial 12 Part B)

The major disadvantage of the globe valve is

• large leakage.
• difficult to maintenance.
• cannot withstand high differential pressure.
• high pressure losses across the valve and potential for clogging.

The globe valve is most commonly used because it

• is cheap.
• does not clog easily.
• can provide tight shut off.
• is very suitable for large pipes.

The type of control valve used in large pipes is

• Ball valve.
• Globe valve.
• Needle valve.
• Butterfly valve.

The valve suitable for applications with frequent clogging is

• Globe valve.
• Fail-open valve.
• Split body valve.
• Throttling valve.

The disadvantage of a double seated valve is it

• is very expensive.
• only has air-to-close type.
• is not commonly available.
• does not provide tight shut off.

A double-seated globe valve is also known as a

• needle valve.
• balance valve.
• saunder valve.
• split body valve.

The type of control valve that provides a tight shut off is

• butterfly valve.
• diaphragm valve.
• single-seated globe valve.
• double-seated globe valve.

Butterfly valve

• provides tight shut off.
• Is a reciprocating valve.
• can perform better than globe valve.
• Is cheap and provides quick opening.

Which of the following is a rotary valve?

• Cage valve.
• Globe valve.
• Butterfly valve.
• Split body valve.

In selecting a control valve the four factors are:

• Environment, safety, valve size, cost.
• Valve characteristic, safety, valve size, cost.
• Valve characteristic, safety, valve size, rangeability.
• Environment, valve characteristic, valve size, rangeability.