Hogged Out Dished Cover

[Afox88]

I am trying to design a dished cover in compress out of a hogged out forging. Does anyone have a suggestion as to best model this configuration, since there is no strict hog out option in compress.

Please advise,

 

[Afox88]

Just to clarify, I mean a box design such as the attached.

 

[marty007]

Typically I would just model it as a bolted cover (blind flange) that is 2.75" thk, essentially not taking any credit for the additional thickness.

 

[Afox88]

Thanks for the response marty. I tried doing that but unfortunately, compress doesn't let me just do a blind flange. It needs to be bolted to an appendix 2 flange. The appendix 2 flanges that I have tried do not have enough bolting to pass, whereas a dished cover has enough bolting. This is considering the same gasket and bolt dimensions.

The way we are modelling it now is using the flange of the dished head, and the calculations for a flat welded cover. That was the closest that we can come up with.

 

[marty007]

What is this bolted to? How are the number and size of bolt selected? Is this bolting to a standard B16.5 flange?

 

[Afox88]

It is bolting to an existing tubesheet. The original design had a different material of construction that led to a much thinner floating head. They changed the material to titanium which is leading to the dished head being way too thick to get formed.