The cushion valve is to minimize the shock and abrupt pressure fluctuation of heavy vehicle such as wheel loader.
 

Working principle

A quick operation or cylinder-stroke-end can cause sudden high pressure in the steering line.
If there is a high pressure at L side, the relief valve opens and the flow goes through main spool and check valve of R port.

Now, the main spool is shifted by the orifice and the flow stops accordingly. Throughout this process, the temporary high pressure comes down and the system is prevented from the shock. This works to both side, to right and left. high pressure in the steering line.
 

Specifications