Pressure Vessel Internals and Attachments

The COMPRESS Attach Menu allows designers to quickly include the mechanical effects of pressure vessel internals and attachments in their designs.  It is also used to analyze common pressure vessel details such as clips, lugs and trunnions.  How COMPRESS deals with individual attachments varies depending on its type and location as described below.

Platforms, Ladders, Insulation, and Piping

Adding attachments directly to a pressure vessel, including  platforms, ladders, piping and insulation, adds weight, and increases the vessel’s projected area and wind loads.  In these cases, COMPRESS takes the attachment’s details and calculates its contribution to the vessel’s mass distribution, horizontal shears, and overturning moments.  The attachment loads are then combined with all other specified loads due to pressure, weight, wind, and seismic in the final COMPRESS design report.

The COMPRESS Attach Menu is used to add Pressure Vessel Platforms, Ladders, Trays, Packed Beds, Insulation and Lining

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Trays, Packed Beds, and Linings

Adding pressure vessel internals such as trays, beds, and linings adds weight but does not increase the vessel’s projected exterior cross sectional area.  COMPRESS uses the specified internals to calculate their contribution to the vessel’s mass distribution and period of vibration.  This in turns flows through the combined weight, wind, and seismic horizontal shears and overturning moment calculations as required.

Clips, Lugs and Trunnions

A very handy option on the COMPRESS Attach Menu is the ability to perform a local stress analysis on small attachments such as clips and lugs.  The local loads and geometries specified are analyzed using WRC 107 / WRC 537.

Lugs Orientation
The COMPRESS Attach Menu Includes a Clips and Lugs Option

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The COMPRESS Attach Menu feature:

  • Lets you add as many attachments and internals as you want

  • Allows you to specify if attachments and internals are present in the empty, test, lift, and shipping cases

  • Calculates the effects of the load combinations on pressure components such as cylinders and transitions

  • Determines how attachments and internals effect pressure vessel supports including skirts, legs, and lugs

  • Calculates how attachments and internals effect skirt base rings, leg base plates, anchor bolts, and foundations

  • Performs WRC 107 / WRC 537 local stress analysis on clips and lugs

COMPRESS Pressure Vessel Design Highlights