The API 5L specification covers pipes to conveying oil, gas, water in the petroleum, gas and water distribution industries.
Grades covered by this specification are A25 ,A ,B (and the following "X" Grades), X42, X46, X52, X56, X60, X65, X70, X80. The two digit number following the "X" indicates the Minimum Yield Strength (in 000’s psi) of pipe produced to this grade.
Sizes (Seamless):1/2" NB – 60" NB,
Sizes (SAW):16" NB – 100" NB,
Sizes (ERW):1/2" NB – 24" NB,
Sizes LSAW/DSAW:16’OD TO 54′ OD (8 MM TO 50 MM THK),
Wall Thickness:SCH10,SCH20,SCH30,STD,SCH40,SCH60,XS,SCH80,SCH100,SCH120,SCH140,SCH160,XXS DIN, JIS standard thickness
API 5L line pipe (Seamless and welded pipe) of all grades have PSL1 and PSL2 two product specifications, they are different on chemical composition, manufacturing processes, mechanical strength, heat treatment, test records, traceability etc. Line pipes in API 5L PSL2 is higher than PSL1. a. PSL is the short name of product standard level.
API 5L Equivalent Grades (ASTM, EN, DIN)
Material grades A53 Gr. B and A106 Gr. B, and also API 5L Gr. X42, are API 5L Gr. B equivalent. It is actually quite common to find on the market pipes that comply, at the same time, with all these specifications ("quadri-norm" marked pipes). While this is true in terms of chemical and mechanical properties, note that the API 5L specification sets more severe requirements and tests than those set for the two equivalent ASTM specifications.
In terms of comparison with EN pipe standards, API 5L Gr. B equivalents are EN 10216-1 P265GH (seamless) and EN 10217-1 P265 (welded) – whereas EN 10216-2 P265 GH is the EN equivalent grade for ASTM A106 Gr. B pipes.