1 .1 Purpose This standard specifies requirements for the qualification , production , and documentation of alloy and carbon steel bolting used in the petroleum and natural gas industries.
1 .2 Applicability This standard applies when referenced by an applicable API equipment standard or otherwise specified as a requirement for compliance.
1 .3 Bolting Specification Levels This standard establishes requirements for three bolting specification levels (BSLs). These three BSL designations define different levels of technical , quality , and qualification requirements , BSL -1 , BSL-2 , and BSL-3. The BSLs are numbered in increasing levels of requirements in order to re flect increasing technical , quality , and qualification criteria.
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