Description

This specification² covers two general classes. WP and CR. of wrought austenitic stainless steel fittings of seamless and welded construction covered by the latest revision of ANSI B 16.9, ANSI B 16.11. ANSI B 16.28, MSS Standard Practice SP-79 and MSS Standard Practice SP-43. Fittings differing from these standards may be furnished in accordance with Supplementary Requirement S9. 

Class WP fittings are subdivided into three subclasses: Classes WP-S, WP-W. and WPWX. They are manufactured to the requirements of ANSI BI6.9, BI6.11, BI6.28, or MSS Standard Practice SP-79, and they shalI have pressure ratings compatible with 9.2. Class WP-S fittings are those manufactured from seamless product by a seamless method of manufacture (marked with class symbol WP-S); Class WP-W fittings contain welds where the fitting fabrication or construction welds have been radiographed (marked with class symbol WP-W); and Class WP-WX fittings are those which contain welds where alI welds have been radiographed (marked with class symbol WP-WX). 

Class CR fittings are those manufactured to the requirements of MSS SP-43, and they shaH have pressure ratings compatible with 9.3. 

This specification does not apply to cast fittings. Cast austenitic-steel piping fittings are covered by Specifications A 351, A 743, and A 744. 

Optional supplementary requirements are provided. When desired, one or more may be specified in the order. 

The values stated in inch-pound units are to be regarded as the standard. The metric equivalents of inch-pound units may be approximate. 

²For ASME Boiler and Pressure Vessel Code applications see related Specification SA-403 in Section II of that Code.