The design and manufacture of pressure vessels and storage tanks is regulated through state legislatures that specify that pressure vessels must conform to appropriate standards. The governing standard for pressure vessels is the 2015 ASME Boiler and Pressure Vessel Code (BPVC).

Pressure vessels are covered in section eight of the BPVC and this section is commonly known as ASME Section VIII. Although non pressurized vertical storage tanks are not pressure vessels, many states require that vertical storage tanks are manufactured to the American Petroleum Institute’s Standard API 650.

If you’re in the market for a pressure vessel or vertical storage tank, here’s how to verify your fabricator’s certifications:

Standard Pressure Vessels

Most pressure vessels will be manufactured under Division 1 of Section VIII of the BPVC. The rules of this division cover most pressure vessels that operate below 3,000 psi. In order to be able to manufacture a pressure vessel under this section of the BPVC, your pressure vessel fabricator must be certified by ASME to apply the U certification mark. Fabricator certifications can be checked by requesting sight of the fabricator’s ASME certificate of authorization. The certificate will specify the name and address of the fabricator and be valid for a period of three years. If there is any doubt, do a certificate holder search.

To obtain certification, a pressure vessel fabricator will have undergone a rigorous on-site certification process conducted by an approved ASME inspector. The fabricator will have demonstrated appropriate manufacturing skills and quality management systems that conform to ASME standards.

Miniature Pressure Vessels

If the pressure vessel is small and operates below a certain pressure, it may be considered a miniature pressure vessel. The requirements for such a vessel are detailed under section U-1(j) of ASME VIII and, provided the vessel complies, it can be exempted from inspection by an ASME approved inspector. However, it must have a certificate of compliance that meets certain requirements. To manufacture a miniature pressure vessel, the pressure vessel fabricator must have a UM certification.

Pressure Vessel Repairs

It’s almost inevitable that a pressure vessel that’s been in service for a long time will develop defects and need repairs. Pressure vessel fabricators wishing to repair pressure vessels must obtain a certificate of authorization as an approved repairer from the National Board of Boiler and Pressure Vessel Inspectors. This certificate authorizes the use of the R stamp, which must be stamped on the pressure vessel nameplate.

Vertical Storage Tanks

Although it’s not mandatory in all states to build vertical storage tanks to API 650, it’s nevertheless good engineering practice. The standard covers flat-bottomed vertical storage tanks used for storing petroleum oil and other liquids.

API does not certify manufacturers but the client has the right to request and examine all documentation pertaining to the storage tank design and manufacture to verify compliance with API 650.

Be Wise and Select the Right Fabricator

If you’re looking for a tank or pressure vessel fabricator, don’t skimp on quality, but choose a company that has proper fabricator certifications. Always check the validity of the fabricator’s ASME certification to make sure their certificates have not expired and that all the details, including the fabricator’s name and address, are correct. If anything does not match, the certificate is invalid.

It’s also wise to conduct a careful site inspection and arrange for an audit of the organization’s manufacturing and control systems. Also speak to their authorized inspection agency and verify their inspection agreement. If the fabricator is out of state, contact the local authorities in your state and check for any additional requirements before placing your order.