Help required to identify markings on studs and nuts on older USA pressure vessel.

[trevornelson]

Hi Guys and Galls,

I am looking to do some refurb work to a seal surface of an older vessel used in a test lab. I will be pushing the seal diameter out slightly so need to reassess the pressure rating and stud capacity. I am struggling to work out what the stud markings indecate as I am from the UK and the vessel originated from the US way before my time.

I will try and post the nut markings on the second post.

Any assistance would be greatly appreciated.

http://www.eng-tips.com/threadminder.cfm?pid=794

Trevor.

 

[trevornelson]

Nut Markings attached.

Thanks
Trevor.

 

[EdStainless]

Have you tried wither the MIL-HDBK-57 (it has been posted here before) or a google image search?
The funny 'H' and the 'oval' sure look like they could be makers marks.
Do the number match any drawings or unit IDs that you have?

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

 

[Duwe6]

What does the U-1 for your vessel say? [probably SA192/193 B7 studs & 2H nuts]

 

[trevornelson]

Thanks you for your advise so far.
I found MIL-HDBK-57 on the internet and will keep a copy for future use also. Unfortunatly I couldnt identify the stamp in the manual.

Regarding the U-1 query. I dont have one unfortunatly. The company bought the vessels 25 years ago for use in the UK and the records cannot be found. The name plate indecates they were originally manufactired in 1968 with a design capasity for 10,500psi but not much else. We only run them at about 3,000 psi. We have many new vessels now but as these are still operational we thought they could be relagated to long term pressure testing ( 1yr).

I will have to put my thinking cap on to where to go from here.

Thanks again

John

 

[r6155]

If the records cannot de found this pressure vessel must be out of service.

Regards
r6155

 

[chicopee]

The H280 number could stand for the heat number. As far as the other numbers, I can not tell.

 

[chicopee]

I just typed SK5 and this site appeared:

http://www.steel-grades.com

It appears to be a reference to mechanical properties of the steel

 

[chicopee]

If you etch the surfaces you may be able to raise the imprint of the manufacturer's stamp and do a google search.