There is no preventative maintenance for these non return valves apart from selecting the correct valves for the system design.
Check valves for use with variable speed drives are difficult to select as the gas volume can vary by a large amount.
When selecting NRV's it is selected against the volume flow that will keep the valve fully open. If the valve is not kept fully open because the volume flow is too low then the piston starts to chatter and bang open and closed causing it to break.
The NRVH has a heavier return spring and will cause the piston to bang up and down until destruction occurs.
A better solution would be the NRV with the lighter spring as it needs less flow to lkeep it open. With discharge gas flows frequencies and harmonics can be a disastrous situation .
With piston compressors if the nrv is not sized correctly the nrv piston will oscillate at the same rate as every piston pulsation say an 8 cylinder compressor running at 1500 rpm running for 1 hour will lead to the nrv piston oscillating 720,000 times an hour . At that rate it won't last for very long, also the Ptfe seat will be smashed to pieces,preventing it from closing tight.
An Nrv should be a smaller size than its surrounding pipe work so that it creates a small pressure drop helping to keep it in the fully open position and allowing the NRV to safely to its job