PIPE 6003 - Introduction to Valves (Chp 18)

Question 1

Regular inspection of a valve is important and items which require close scrutiny are the:

A) Stuffing box and spindle threads
B) Disc and seat
C) Steam and body
D) Hand wheel and packing
E) Seat and stem

Answer 1

B) Disc and seat

Question 2

The valve that provides very fine flow control is the:

A) Check valve
B) Gate valve
C) Butterfly valve
D) Ball valve
E) Needle valve

Answer 2

E) Needle valve

Question 3

Advantages of Butterfly valves are that they:

1. Are “relatively light” and easy to operate
2. Are “self cleaning”
3. Provide “negligible” pressure drop when fully open
4. Can have the disc lubricated while in operation
5. Are self adjusting so alignment is not required during installation

A) 2, 4
B) 1, 3
C) 1, 2, 5
D) 3, 4, 5
E) 1, 2, 3

Answer 3

E) 1, 2, 3
relatively light
self cleaning
self adjusting

Question 4

The purpose of the non-return stop valve is to:

A) Drain condensate from the main steam header
B) Prevent the safety valve from popping
C) Prevent water from entering the steam header
D) Regulate the flow of steam from the boiler
E) Prevent the back flow of steam

Answer 4

E) Prevent the “back flow” of steam

Note: PREVENT Backflow

Question 5

A valve which requires specific and routine lubrication is the:

A) Check valve
B) Globe valve
C) Tapered plug valve
D) Pressure reducing valve
E) Butterfly valve

Answer 5

C) Tapered plug valve

NOTE: ROUTINE LUBRICATION

Question 6

A check valve is a valve that:

A) Allows flow in two directions
B) Does not allow any flow at all
C) Has a locking spindle
D) Allows flow in one direction only
E) Allows flow at regular intervals

Answer 6

D) Allows flow in “one direction” only

NOTE: ONE DIRECTION

Question 7

A valve that often “contains a dashpot” to cushion the action of the valve is the:

A) Lift check valve
B) Pressure regulating valve
C) Safety valve
D) Swing check valve
E) Needle valve

Answer 7

A) Lift check valve

IS A VALVE THAT “CONTAINS A DASHPOT’’

Question 8

A valve having minimum wire drawing and seat erosion is the:

A) Gate valve
B) Plug valve
C) Hand valve
D) Wedge gate valve
E) Globe valve

Answer 8

E) Globe valve

Note: MINIMUM WIRE

Question 9

A gate valve:

1. Has less restriction in a line than a globe valve
2. Should be operated either fully open or fully closed
3. Is used to throttle flow
4. Is used for different applications than a globe valve

A) 2, 4
B) 1, 2, 3, 4
C) 1, 3, 4
D) 1, 2, 4
E) 2, 3, 4

Answer 9

D) 1, 2, 4
Gate Valve:
less restriction,
fully open/close,
different applications

Question 10

A valve that has the “greatest capability of handling slurries and fluids” with high suspended solids is the:

A) Plug valve
B) Ball valve
C) Needle valve
D) Globe valve
E) Gate valve

Answer 10

B) Ball valve

Note: “greatest capability of handling slurries and fluids”

Question 11

Increasing the spring tension of a pressure regulating valve will:

A) Increase the regulated pressure downstream of the valve
B) Cause the valve to go to the wide open position
C) Close the valve tight
D) Decrease the regulated pressure downstream of the valve
E) Reduce or minimize the cycling or “hunting” of the valve

Answer 11

A) Increase the regulated pressure downstream of the valve

Question 12

Relative to valves, a frequent cause of serious accidents is due to:

A) A lack of valve maintenance
B) Wrong materials of construction
C) Inadequate operational training
D) Manufacturing defects
E) Valves being of the wrong size

Answer 12

B) Wrong materials of construction

Question 13

When valve stem leaks are fixed by tightening the packing gland:

A) Valve packing doesn’t require maintenance
B) Use a thicker packing
C) Always tighten up bolts evenly
D) Leave some leakage to lubricate the rotating shafts
E) Tighten the packing as much as possible to prevent future leaks

Answer 13

C) Always tighten up bolts evenly