Man way of pressure vessel relation to girth flange 1

[Jimjoe]

I have been inspecting for a contractor that is doing work for a petroleum refinery. They have bolting and torquing handbooks that their contractors follow and there has been some debate about manways.
They have sections broke down by flange rating, size, and class. As for the, "pressure vessel and girth flanges", they are strictly broken down by stud size.
The debate has been about whether the man ways to the pressure vessels fall under the raised face torque specifications or if they fall under the pressure vessel girth flange category.
The difference in torque is approximately 180 ft lbs which when it comes to hydraulic or pneumatic torquing.. is not much different, sometimes as little as 5 or 6 psi.
The main question is whether the man way to a pressure vessel is more relatable to a girth flange than it is to a flange of two bolt mated pipe flanges.

 

[RJW000]

Does the refinery not specify any bolting guidance for the contractor to follow? They let them use random handbooks? Who knows the basis for those specified torque values? Targeting a stud stress with no regard to gasket style and dimensions is an outdated practice.

In terms of pressure loading the piping flange is similar to manways or girth flanges w/cover. Only one sided pressure loading. Tube sheets are a different story.

Follow ASME PCC-1!

 

[Jimjoe]

I wasn't terribly explicit about the details of the handbooks in order to get to the exact question. The client has designed the handbooks to follow code as well as to express their desires, such as, the use of which thread lubricant, the amount, and even brand. They base torque off of gasket type, material, flange metallurgy, bolt size/ material, and as said flange type/ classification.

The confusion lied with in the headings of torque pages, I wish I still had the handbook but I left it when I left.

The title, "pressure vessel and girth flanges" got boilermakers stuck on one torque where as the QC, pipe fitter by trade, wanted them to follow the raised face flange torque. Difference in torque between the two being at most 180ft lbs, depending on flange size.

I had always been curious if the man way of a pressure vessel fell in the girth flange category, despite it having asme b16.5 ratings.