Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
20 Cards in this Set
- Front
- Back
|
What does the term WOG mean |
Water, oil gas |
|
|
Which valve can be used for throttling |
Globe |
|
|
What is the purpose of a balance valve |
Less force is required to operate the valve so smaller actuators may be used |
|
|
What two designs of operation are used to actuate valves |
Linear (reciprocating) Rotary |
|
|
Identify two advantages of hydraulic actuators |
Drive and operate heavier loads More precise control |
|
|
What is the purpose of a rupture disc |
The disc ruptures at a preset pressure |
|
|
Why is valve lapping done on pipe valves |
Lapping two mating surfaces of a valve smoothes and flattens the surfaces and makes the parts precisely fit each other |
|
|
What does the term reps king a valve encompass |
Remove old packing, inspect and clean valve spindle and stuffing box, then install new packing into the stuffing box. Complete by installing the gland flange (follower) and tighten down evenly |
|
|
Identify four types of NDT procedures used for testing valves and valve components |
Dye penetrant Magnetic particle Radiography Ultrasonic methods |
|
|
Body |
The main case of the valve which bourse the flow-controlling parts |
|
|
Bonnet |
The part of the valve through which the stem extends. It contains the means for sealing the fluid in the valve |
|
|
Closure element |
The part that closes off the flow of fluid in a valve. It may be needle, disc, plug, butterfly disc, ball or diaphragm, depending on the valve type |
|
|
Gaskets |
Gaskets seal flanged joints. The three main types of gaskets are -flat ring- which cover the face of the flange to the inside edge of the bolt holes -full face, which cover the full face of the flange and have holes punched in them for the passage of the flange mounting bolts -metal ring- (oval or octagonal cross-sectional shape) which fit into machined grooves in the face of the flanges |
|
|
Gland |
A metal ring at the top of the stuffing box to push down on the packing to compress it and force it against the valve stem |
|
|
Gland flange |
The metal plate on a larger valve that pushes down on the gland. Bolts pass through the holes in the plate to tighten it in position |
|
|
Handle or hand wheel |
Manual actuator, which may be a lever or a wheel to open and close the valve |
|
|
Motor control mechanisms |
Electric, hydraulic or pneumatic motor valve actuators |
|
|
Packing /mechanical seals |
The devices used for sealing valve stems from leakage. Packing is a cord-like material with a cross-section, usually manufactured in split rings. It is installed with the splits in the rings staggered for sealing purposes |
|
|
Spindle |
The stem of a valve. It is the shaft that causes the closure element to move |
|
|
Stationary inserts |
Replaceable parts of valves, such as the seat rings and screw-in guide tubes used in some valves |
