This guide covers standard specification for three classes of gray iron for castings intended for use as valve pressure retaining parts, pipe fittings, and flanges. Chemical analysis shall be performed in each lot and shall conform to the required chemical composition for phosphorous and sulfur. Tension test shall be conducted on each class of gray iron castings and shall conform to the specified values of tensile strength. Tension test specimens shall have threaded ends and shall conform to the prescribed dimensions.

1.1 This specification covers three classes of gray iron for castings intended for use as valve pressure-retaining parts, pipe fittings, and flanges.

1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

Note 1: The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the standard.

1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.