Darrel Kost (Civil/Environmental)(OP)5 Aug 19 22:32

[Darrel Kost]

Darrel Kost (Civil/Environmental)(OP)5 Aug 19 22:32
I am presently inspecting a number of old in-service air compressor tanks that I need to compare measured UT readings for the shell and heads against allowable thickness.
For example,
350psi, 2.67ft diameter, 7.1 feet long, 235 gallons;
350psi, 1.6ft diameter, 14.75 ft. long, 235 gallons;
120 psi, 2 ft diameter, 5.85ft long, 120 gallons, etc.
40 psi, 4.6ft diameter, 15.15 ft long, 1320 gallons
120psi, 6.0 ft diameter, 13.7 ft long, 2530 gallons
Help!!

 

[TGS4]

Exactly what type of help are you looking for?

 

[marty007]

Dig up the original fabrication drawings and find the nominal thickness and corrosion allowance. Nominal thickness - corrosion allowance = minimum allowed thickness.

If you don't have the drawings available, do you have an MDR?

Otherwise, you'll likely have to perform new calcs to the original code of construction.

 

[Darrel Kost]

There are no original fabrication drawings
No MDR
I only have present day UT readings for the shell and heads for each compressor.
Looks like performing calcs.
Do you know someone that would be interested in doing this?
I'm an environmental engineer P.E., not a mechanical engineer!!

 

[SnTMan]

Darrel Kost, do they have an ASME nameplate?

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[marty007]

Your best bet might be to find an NBIC 'R' stamp certified repair organization in your area. Repairs deal with older equipment, and often require recalculation of the existing equipment. You might be able to find someone locally that can perform the required calculations.

Be careful that you're not straying outside of your Engineering Field of Practice. Do you have any training in the field of pressure equipment?

 

[Darrel Kost]

There is no ASME nameplate on the tanks.

I was hired only to perform ultrasonic thickness testing of the compressors and compare to original thickness.

I'll look into the NBIC "R" repair organization and for someone to perform the calculations

Thanks to all for your help.

 

[thebard3]

Without a board stamp they sound like scrap metal to me.

Brad Waybright

It's all okay as long as it's okay.

 

[r6155]

@ marty007
See API 510 required thickness
The minimum thickness without corrosion allowance for each element of a pressure vessel based on the appropriate design code calculations and code allowable stress that consider pressure, mechanical, and structural loadings.

Regards

 

[TGS4]

@Darrel - it's more than just calculations. Please see this post about how to handle equipment lacking documentation.