1948 Pressure Vessel Code

[RPRad]

I have to review the fitness of a carbon steel welded vessel constructed in 1948, no MDR is available for the vessel. A couple of the things I need to know to get the process started and I was hoping someone might have an answer to these questions:

1)The stated Tensile Strength of the carbon steel shell and head is listed on the nameplate as 55,000 psi, given that, the material of construction is possibly a SA285 Gr.C material (or perhaps SA283 Gr. C material I suppose). Anybody know what safety factor was in effect at the time the vessel was constructed? I recall it initially starting at 5 in the early codes, I believe they lowered it to 4 around the time of WWII. Did it go back up again after the war and then get lowered again around 1955? or did it stay at 4?

2)What radiographic joint efficiencies were in effect at this time? Looks to me like some must have been done in order to utilize the shell and head thickness they have used. Were there any min requirements in effect back then?

Thxs

 

[metengr]

I have a 1952 ASME Section I Code book, the design margin was 4:1.
Weld joint efficiency was either 0.90 or 0.95. The higher weld joint efficiency 0.95 was used if the weld reinforcement was removed and ground flush with the plate.

 

[RPRad]

Yes, SF=4 seems to agree with what I have been able to find so far, although I keeping finding the odd note that says they changed it back to 5 after the war...4 would be more consistent with the the wall thickness on the vessel.

I knew there was something funky about the Weld Joint E back then. So was it .90 for 100% radiography on the seam? If they did spot what did they get 0.80?

In your 1952 code how did they treat a seamless head...did you have to the spot RT to get the full joint efficiency?

 

[normet]

From 1946 to 1950 the factor was 5 , but in 1950 it was changed to 4.

 

[chicopee]

If this boiler has NB/ASME number, you should be able toget a copy of the MDR from the National Board of Boilers and Pressure vessels.

 

[RPRad]

Unfortunately there is no national board number on it, probably manufactured in Canada. Oddly enough the regulatory authority likely does have the MDR on microfiche...but since the advent of computers..you cant convince them to go find it...too much work!..spoiled

 

[RPRad]

Have now noticed that vessel has a Para U69 designation...what does that mean?