Bolted Joints

Bolted joints in piping systems in order to connect and disconnect valves, pumps and other equipment and accessories to piping systems have been used through many centuries. One example is cast iron flanges and pipes installed in the waterworks of Versailles in 1685, and which were in service until 1939.

Since bolted joints are normally interfaces between supplies from independent suppliers of valves, pumps, vessels and flanges, these interfaces have been subject to rigid standardization for a period of more than hundred years. This standardization includes flanges to fit with standardized pipe diameters and their wall thicknesses and a huge number of standardized material qualities. It includes valves, pumps and other accessories with flanged ends, and it includes also bolts and nuts and gaskets to connect and seal between the flanges and the flanged products.

The predominant design code for pressure piping in the petroleum industry over the last 60-70 years has been the ASME B31.3, Process Piping. This American code is used all over the world today in oil and gas production, refinery and petrochemical industries. This code makes reference to product standards, which fulfil the requirements of the code, including flange and valve standards, ASME B16.5, ASME B16.47, ASME B16.34 etc.