Cost of Safety valve maintenance

[europipe]

Hello You Experts out there.

I´ve just been thrown from technical into cost estimating, bleh,
is there someone who knows approx. prices of revision, adjusting and maintenance of safety valves.
Say from 1"x2" to 8"x12"
I would be much obliged.

thanks in advance,
Jaap

 

[gerhardl]

Suggestion:

A. No easy way if not any historical data, and if you do not have a complete offer for maintenance service (this can be bought from specialiced companies - you could ask one of those)

B. The long way
1. Log and list all valves, technical data, historical cost, cost for spares, cost for in/out of valves, time for test, time for repair.
2. Put in excel spreadsheet.
3. Go extra round finding costs not available in first round, interview with suppliers or maintenance people.
4. Estimates or prolongation for what still not found from available data.
5. Add or modify from age of valve, local experience, required tests per periode, service conditions for valve
6. Calculate sparepart costs (if any), service cost pr. hour (if any) times number of services per time periode (once a year minimum for functional test, repairs and service cost more seldom?)for each single valve to get total cost.
7.Give estimate of tolerance for total ( Less 10% plus 30%? for longer run and plus minus more than 50% for unplanned and irregular repairs???)

 

[europipe]

Thanks Gerhard,

Most of the safeties had been in maintenance service in about 1993-1995.
In how much time should springs be replaced and is there no easy way to make a guestimate?
The safeties are also from many different vendors.

Greetings
Jaap

 

[gerhardl]

Hello Europipe,

I suggest you ask the supplier of the most used make of PSV for typical data on spring lifetime and preventive changing or tests. I would think functional test for the total valve, seat and/or seat sealing (grinding and replacement) would form the greatest part of the cost. But all depending of type of service, how critical and though application and demands you have.

 

[europipe]

Thanks Gerhard,

but I dont have that time,
They want the price yesterday as usual
Its a guestimate