Repair instruction for Seat Ball Valve

[Rio Risnaldi]

Dear Engineer,


How are you?
Trusted you very well today.

By The way, I have Issue, That I found seat Ball have damaged on the sealing contact (As Per Picture). We dont have detail spec material, So we using Positive Material Identification (PMI) for identification material.

As the result, Base material seat is 416SS.

our first recommendation before using PMI, is:

"Cleaning, rebuild the contact surface of damaged area by tungsten carbide + machining + lapping."

after we known that material 416SS, we have other option for rebuild by weld using STELLITE 6.

Need your advice for the correct recomendation and instruction for repair, as soon as possible.

Thanks
Rio

 

[gerhardl]

Hello Rio Risnaldi,

To keep a ballvalve tight over time the two most important factors are geometrical precision and accuracy in the two matching sealing surfaces, the second is accurate and total closing position.

Your picture shows damage that might be (but not necessarily is) the result of cavitation by slight (hair-size) openings, sticking particles, or else also material broken away.

From a material description only it is almost impossible to advice on best material, otherwise than that a repair process costing more, usually also represent a better quality.

More details, better answers. (Pressure class, application details in full, operation details, expectation of total standing time without repair, size etc. etc.)


Good luck!