Supports

Module from the Pressure Vessel Engineering Curriculum curriculum.

Module 6 - Supports, Saddles, and Skirts · Learning Objectives · 1. Select support type: saddle, skirt, legs, lugs by orientation and service · 2. Apply Zick analysis for horizontal vessel on two saddles · 3. Check WRC 107 / 297 local loads at lug attachments · 4. Verify skirt design for wind, seismic, and vessel weight · 5. Design anchor chairs and base ring for uplift + moment · Support Type Selection

Type	Orientation	Typical Use	Pros	Cons	Design Ref
Two saddles	Horizontal	Drums, exchangers	Simple, common	Zick needs careful check	Zick L.P. Art
Skirt	Vertical, tall	Towers, reactors	Stable, insulated base	Fireproofing	API 650 / PIP
Legs	Vertical, short	Small drums	Cheap	Not for tall	UG-54
Lugs	Vertical (on shell)	Reboilers, small	Simple	Local stress WRC	WRC 107
Ring girder	Very large dia	Spheres, FCC	Uniform load	Costly	Custom FEA

Source: Pressure_Vessel_Engineering_Curriculum_v1.xlsx · Sheet: Supports

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