backseat - meaning - valves

[JACEK1]

Hello again,

I would like you to help me understand the meaning of "backseat", both as a noun and a verb.

The source: chestertondocs.chesterton.com/Stationary/Page17AskExpertSept.pdf

 

[SoothingDave]

You know that a valve will seal against a seat when it is closed, right?

With a backseat, the valve also seals against another seat when it is fully open. This prevents the process fluid from exiting out the top of the valve, allowing maintenance on the packing of the valve.


"To backseat" is to open the valve fully against the back sealing surface.

 

[JACEK1]

What about the "backseat" as a noun?

 

[SoothingDave]

The backseat is the sealing surface for the fully-opened position.

 

[Tdol]

I had no idea until I read this thread that backseat could be a verb.

 

[SoothingDave]

There is no noun in English so noble that it can't be verbed.