Types of valves

Butterfly valve

1.valve liner
2.valve blade,
3.valve body,
4.upper seal,
5.valve spindle,
6.key,
7.upper bearing,
8.pins,
9.lower bearing,
10.lower seal,

Retention valve, non-return valve, check valve

1) when the disc is not attached to the spindle, the globe valve is considered to be a screw-down nonreturn valve (SDNR).

1.body,
2 bonnet,
3 gland flange
4 gland,
5A disc (stop type),
5B disc (piston SDNR),
6 disc stem nut,
7A stem (stop type),
7B stem (piston SDNR),
8 bonnet gasket,
9 gland packing,
10 bonnet studs,
11 bonnet stud nuts,
12 yoke bush,
13 handwheel,
14 handwheel nut, tack weld, stellite,

2) without a stem to screw down the flow interrupting component, the non-return valve is of the freelifting type.
Note : the flow-interrupting component may be a disc (see figure) or may be a bail (ball check valve),

flap check valve, flap valve, swing check valve,
plug valve, ball plug valve, ball valve,cylindrical plug valve,
cock, bib, bib-cock, faucet, tap,
3 guides cast integral with body,
cover studs,
nuts,
gasket,
body,
disc,
bore,

sleeve-packed cylindrical plug cock

lever
lever bolt
split ring
plug
packing sleeve
tightening nut

valve classification according to…

FLUID FLOW:

full way valve, full bore valve (e.g. gate valve, butterfly valve)
throttle valve (e.g. globe valve, needle valve, piston valve)

FLANGE CONFIGURATION:

straight-through valve, in-line valve, angle valve

FUNCTION

dump valve,
flow diversion valve,
relief valve, safety valve, sea suction valve etc.

in the gate valve,

closing by interposing a flat or tapered element (gate or wedge) transversely across the axis of the opening.

in the globe valve,

closing by pressing a disc or plug axially against the opening.