Asme code understanding

[Sushmanth]

Some sections in Asme bpvc Sec II like SA 105, SA 182 specifies the maximum forging weight to be 10000 lb or 4540 kg. If this weight limit exceeds it is stated that user shall refer to other specifications like SA 965 or something else etc..
Does anyone know the reason or basis behind this forging weight limitation?
What if the same specification is used to make forgings exceeding this weight?

 

[Geoff13]

Does anyone know the reason or basis behind this forging weight limitation?

The committees that wrote and now maintain SA-105 and SA-182 typically don't explain their reasons for the values. I consider SA-105 to be a junk spec, and probably wouldn't use it beyond standard B16.5 flanges. Of course I'm in Canada and the temperatures generally require SA-350, so I'm biased in my views about SA-105.

What if the same specification is used to make forgings exceeding this weight?

The 10,000 lb limit is in the scope statement of both specs. Thus a forging weighing more than 10,000 lbs can't be SA-105 or SA-182. Any reputable manufacturer should require you to select an alternate specification.

Why would you want to use SA-105 or SA-182 outside their specification limits? By the time a forging is that big is there any added cost using a spec that doesn't limit the weight?

 

[r6155]

Is this flange the one you use for pipes or pressure vessels?

Regards