Valves PHEP Flashcards
A program designed to improve valve care and operating and maintenance procedures will promote
plant reliablility
plant safety
plant efficiency
All three
The metal offering the greatest resistance to cavitation is
stainless steel
Chromium and nickel are both added to steel to improve its ability to
resist acid corrosion and cavitation
Resistance to flow through a valve can be caused by
metal roughness
protuberances inside the valve
change in the direction of flow
all three
Which of the below fittings would not normally be used with a gate valve?
outside lever and weight
A quick-opening valve should be closed slowly to
prevent hydraulic shock caused by water hammer
All of the below valves may be float operated except
blowoff valves
Which of the below valves would normally be used to regulate fluid volume in a hydroelectric plant?
needle valves
What type of gate valve would most likely be used to reduce as much as possible the erosive action of water flowing at high velocity through high pressure gates?
Paradox
All of the below valves are normally used for crest control except
paradox gate
Valves are rated by the [BLANK] and temperature they are designed to handle
pressure
The highest working pressure rating used for valves is?
Steam
Pressure drop can be defined as a [BLANK] in energy or a [BLANK] in pressure, in a pipeline, due to the resistance in it
loss - reduction
What type of connections would you use on a large valve?
flanged
A [BLANK] valve has a āsā shaped path and is used for [BLANK] flow
globe - throttling
