different types of valves found in a refinery

Some quick comments to get you started:

Chain operated valves are usually up high in a pipe rack and instead of a handle, they have a chain hanging down to operate it without climbing up in the pipe rack or getting a ladder....

Fail closed=when signal is lost or power or air the valve will close. An example is the steam valve on a heat exchanger, in the event of an emergency shutdown, such as a power outage, usually you want the heat off, so the valve fails in the safest mode or closed.

Fail open = when signal is lost or power or air the valve will open. An example would be cooling water control valve, you don't usually want to lose cooling during an emergency so it fails open.

fail indeterminate = no one knows what it will do when the signal is lost or power or air.

fail locked = when signal is lost it stays in the last position whatever that may be.

normally closed = during normal operation this valve will be closed, sometimes the body will be darkened in on a P&ID drawing or a NC will be below the valve depicted on the drawing to show this.

Gear operated = gear are used to give the operator of the valve a mechanical advantage in order to close the valve, usually on large valves.

Lock out = a tag is placed on the valve with a lock to keep someone from inadvertently opening it, a safety program.

lock closed = a tag, chain and lock, carseal, or other means to keep someone from causally opening a valve, or inadvertently opening, not a normal operation, several people will be involved in order to open a lock closed valve.

Hope this gets you started.

A. The following site is free download : Control Valve Handbook .

B. For all valves, I have a very interesting handbook "Valve Selection Handbook" in PDF format, 337 pages with size 43 M, how can I send it?

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The following link is for free downloading of PDF file format "Valve Selection Handbook": http://www.4shared.com/file/121064139/74dd5b3d/Valve_Selection_Handbook_4th_Edition.html