C05_03_-_J_3__QQ-S-681b-Federal_Specifications.pdf

This is a Federal Specification for Steel Castings (QQ-S-681b), dated November 6, 1941, with amendments through July 18, 1952, approved by the Director of Procurement for use by all federal departments and establishments.

The specification establishes requirements for steel castings in nine classes: Class X (common, no heat treatment or physical tests); Class O (common, annealed, no physical tests); Class 1 (soft, annealed, tested); Class 2 (medium, annealed, normalized, or normalized and tempered, tested); Class 3 (hard, annealed, tested); and Classes 4A1, 4A2, 4B1, 4B2, 4B3, 4C1, 4C2, 4C3, and 4C4 (meeting specific physical requirements with various heat treatments). Steel castings must be produced using electric (arc or induction) or open hearth processes and must be uniform in quality, free from injurious blowholes, porosity, hard spots, shrinkage defects, cracks, and other defects. Castings must be cleaned with heads and gates removed, and when specified, inspected in the green condition. The specification provides detailed heat treatment procedures for each class, including annealing, normalizing, tempering, and quenching requirements with specific temperature ranges and cooling methods. Chemical composition requirements and minimum physical properties (tensile strength, yield point, elongation, reduction of area, and cold bend capability) are specified in Table I for each class. All castings must undergo surface inspection by a government inspector, with tension and bend tests performed on test coupons cast on the body of castings (except Classes X and O). Chemical analysis of each melt must be furnished by the contractor, and pilot castings may be required when specified. Castings must be properly packaged, marked with material grade and quantity, contractor name, and contract or purchase order number for shipment.