BS EN ISO 17781:2017

This standard BS EN ISO 17781:2017 Petroleum, petrochemical and natural gas industries. Test methods for quality control of microstructure of ferritic/austenitic (duplex) stainless steels is classified in these ICS categories:

• 75.180.01 Equipment for petroleum and natural gas industries in general

This document specifies quality control testing methods and test conditions for the characterization of microstructure in relation to relevant properties in ferritic/austenitic (duplex) stainless steel components supplied in the solution annealed condition and fabrication welds in the as welded condition.

This document supplements the relevant product and fabrication standards with respect to destructive testing methods including sampling of test specimens, test conditions and test acceptance criteria to show freedom from deleterious intermetallic phases and precipitates in duplex stainless steels. In addition, this document specifies the documentation of testing and test results by the testing laboratory.

NOTE 1 This document is based upon experience with duplex stainless steels in offshore oil and gas industry applications including topside and subsea hydrocarbon service, sea water service, as well as structural use.

NOTE 2 The austenite spacing is relevant to the susceptibility of duplex stainless steels to hydrogen-induced stress cracking (HISC) in subsea applications where cathodic protection is applied. This falls outside the scope of this document. Reference is made to DNV/GL RP‑F112^[4].