General construction, operation, and theory of valves.

DOE-STD-1161-2003

Mechanical systems personnel shall demonstrate a working level knowledge of the general

construction, operation, and theory of valves.

Supporting Knowledge and/or Skills

Define the following terms as they relate to valves:

Disc

Seat

Throttle

Actuator

Bridgewall mark

Packing

Using a drawing of a valve, identify which of the following general types of valve it is

and, describe its normal design application in a piping system:

Gate

Globe

Ball

Check

Butterfly

Regulating/reducing

Discuss why the design of a globe valve enables it to throttle fluids efficiently.

Using a diagram of a globe valve body showing the bridgewall mark, identify how the

valve must be oriented in the system related to flow.

Discuss why gate valves, ball valves, and butterfly valves should never be used to throttle

flow.

Discuss how cavitation occurs in valves and state any harmful effects that can result from

Describe the construction and principle of operation for the following types of valve

actuators:

Manual

Electric

Pneumatic

Hydraulic

Describe the principles of operation and applications for modulating and pressure

reducing valves.

10.

Mechanical systems personnel shall demonstrate a working level knowledge of safety and

relief devices.