Piston Accumulator Testing Requirements

[kbplantier]

Hello, I am looking at the feasibility of repairing a piston accumulator. The primary problem is the seal leaking by on a horizontal installation. The assumption is that the accumulator sits stagnant and over time the seal settles and leakage occurs. We can easily replace the seals and guide rings on the piston. I am struggling on how to re-certify this cylinder to send back to the customer. Our initial discussion centered around sending with or without a pre-charge. Researching the CFR, I've concluded that it needs to be shipped without a pre-charge to eliminate that hassle. The customer will need to be able to adjust the pre-charge on site anyways. However, what requirements are necessary in order to re-certify the accumulator. Does it require a retest at all for just replacing soft goods and no modifications to the component?

Any help would be appreciated.

Best Regards