When referring to the "king" valve, most air conditioning technicians are referring to the valve which is found downstream from a liquid line receiver. It is also commonly referred to as a liquid line service valve or an isolation valve. The name King valve is what Carrier calls its service valves. If you call a wholesaler or manufacturer for a king valve the answer you will receive is "Sir, we don't carry king valves." Every manufacturer calls service valves something different.
A queen valve is the service valve (isolation valve) located at the inlet of the liquid receiver (between the condenser outlet and the liquid receiver). The king valve is the service valve at the outlet of the liquid receiver (between the liquid receiver and the liquid line). Queen valves seem to be in use much less than king valves.
I assume you meant to say "Where is a king valve in refrigeration?" Anyhow, it is usually located downstream from a liquid line receiver.
king valve
Valve pocketing is when a valve is hammering the valve seat.mostly due to miss adjusted valve spring/wrong valve spring/to strong of a valve spring or valve stem to short.Makes the valve seat deeper.
tricuspid valve,bicuspid valve and pulmonary valve
A valve spring "keeper" or AKA a valve spring "retainer" is used to lock a valve spring to the valve.
# The PCV valve is located in the valve cover # Detach the hose from the valve then unscrew the valve from the valve cover
Spill valve is a overflow valve.
Ileocecal valve
The valve guide is a precise hole in the head that the valve stem slides in. The valve is retained by the retainer and two valve locks.
left atrioventricular valve and left mitral valve
the triscuspid valve is the valve in a bathroom sink.