Induced Membrane Stresses Limit in Hydrotest Condition as per ASME VIII-2 ED.07

I would guess the same to be honest i would say its because they are making advances in making the technology itself smaller, in the initial stages it is always the case that initially when reducing insulation yield it would ofcourse make sense for higher yield stress until the containment unit is within sufficient parameters. Baby steps baby! :)

Peace out.

Uncleste

There are two reasons:

1^st. An improvement of the material itself and its characteristics was achieved, or

2^nd. A higher factor of safety was selected due to implementing such rules with higher restriction in stages of design, fabrication and/or erection.

At the end, you can proceed such a design and finding a lesser wall thickness of pipe or vessel.

thanks for the satisfactory reply to my post. but i have one question related to it....

how an improvement of material itself is achieved in new code....it gives just lower factor of safety nothing else.....is there any relations with material properties changes.....? please sir clarify this point to me....

Improvement of material also includes any additional tests, inspections, higher acceptance criteria, ... etc. whatever thru its production in the mill or during fabrication in workshop. This is clear when you make a comparison between ASME VIII-1 & VIII-2.

Also, just changing the acceptance criteria of the percentage of an element of its chemical composition, can affect the factor of safety used and inturn the allowable tensile strength of material.