BS 1515-1:1965

This British Standard covers the design, construction, inspection, testing and certification of unfired fusion welded pressure vessels of carbon and ferritic alloy steels utilizing higher design stresses than those permitted by B.S. 1500, 'Fusion welded pressure vessels for general purposes', Part 1, 'Carbon and low alloy steels'. The term 'pressure vessel' as used in this standard includes branches up to the point of connection to the connecting piping by bolting, screwing or welding.