Compressors - Valves Flashcards
What happens if you put in a suction valve in the discharge port or put it in backwards?
Could cause excessive Rod Loading which would reduce rod reversal which provides lubrication for the crosshead pin and connecting rod
Name 4 main components of a compressor valve?
Seat - for the sealing element to seal against
Guard - to act as a backstop and limit travel
Sealing element - to open and close and provide a seal
Assembly elements - to hold valve together
What does valve lift refer to?
The distance travelled by the valve sealing element. Too much travel causes premature wear which causes increased impact, valve flutter and late closing.
What advantages do V shaped sealing elements provide?
better flow characteristics
Which valve between the intake and exhaust will need to be replaced first and why?
The exhaust because the pressure is so much higher
Which valve has the least restriction of flow?
the ring valve because it doesn’t have reducing webs like the plate style does.
What are the 3 measurements on a channel valve?
side clearance
end clearance
lift
What is a common way to check if a valve is sealing when you are out in the field?
Perform a leak test by filling the seat port of the valve with fluid and see if it leaks.
What are Dampened Disc Valves and what are they best suited for?
They use 2 or more dampening discs along with a sealing disc. The sealing disc seals and the dampening discs help work together to reduce the impact of opening. They are best for high RPM applications.
What type of application are synthetic rings used for and what are the advantages of using them?
Non-lube because they are lighter weight, limit damage to the other compressor components and reduce noise level.
When is a poppet valve the best choice?
when there is condensation or other liquid in the gas stream because the sealing element is synthetic not metal.
How can you tell if a valve is a suction or discharge valve?
Discharge valve sealing elements open toward the nut
What is a feather valve?
It uses a flat rectangular strip of metal that flexes into a concave slot. It has no springs.
When reconditioning a valve, can you just machine the seat and nothing else?
No, because the machining will also effect other parts of the valve.
When removing the valve cover, why do you loosen the valve cover nut.
To ensure you have enough clearance for the valve chair inside when you tighten it back up
