If you belong to the North American pressure vessel manufacture sector, then you must adhere to the safety requirements for pressure vessel design and fabrication. The cutting, bending, welding and assembling processes of metals for vessel fabrication are strictly controlled.
ASME (The American Society of Mechanical Engineers) has established a code for pressure vessel fabrication. ASME standard basically provides rules for design and fabrication of pressure vessels in order to validate their safety, increase their longevity and functional value. However, as per the specifications given by the client, manufacturers can fabricate pressure vessels that exceed the requirements of the ASME Code. Other geographic jurisdictions have independent design and manufacturing codes and standards which may or may not adopt elements of the ASME Code.
The ASME BPVC Standards Section VIII governs the of pressure vessel manufacture (and fabrication) comprises of 3 divisions. The first division deals with requirements that are mandatory as well as non-mandatory guidance for designing and fabrication techniques along with choice of material. The latter two divisions cover alternative rules for construction and welding of parts of pressure vessels.
Steps Involved in Pressure Vessel Fabrication:
In order to assemble (fabricate) and tack the welded metal parts in place during the construction of pressure vessels some or all of the following steps may be required:
- Selection of raw material (commonly used material for fabrication are plate, pipe, forgings, structural shapes, welding rod or wire, etc.).
- Cutting and burning of the raw material as per the specified requirements.
- Machining of certain parts if needed.
- Assembling and welding the parts of pressure vessel.
- Cooling the weldment and sand blasting it before applying primer and paint.