This specification covers Grade 100 heat-treated alloy steel chain for such applications as slings, lifting assemblies, and load binding. The alloy steel shall be fully killed and have an austenitic grain size of five or finer. The steel shall be made by the electric welding or gas welding process. After welding, alloy steel chain shall be heat treated before applying the proof test. Heat and product analysis shall be performed and shall meet the required chemical composition in carbon, phosphorus, and sulfur. All chain shall be tested to at least the proof load and breaking force test specimen shall consist of a length from the lot containing at least the number of links. All chain shall be in the quenched and tempered condition before the elongation is measured.

1.1 This specification covers Grade 100 heat-treated alloy steel chain for such applications as slings, lifting assemblies, and load binding. For overhead lifting applications, only alloy chain should be used.

Note 1: This specification does not cover alloy steel chain for pocket wheel applications.

1.2 This specification is a performance standard for Grade 100 chain used between −20 °F and 400 °F [−29 °C and 205 °C]. The chain manufacturer should be contacted for use at temperatures outside this range.

1.3 The chain grade is based on the nominal stress in the link at the design breaking force strength. It is calculated by taking the minimum breaking force load and dividing by two times the nominal cross-sectional area of the link.

1.4 The values stated in either SI units or in other units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.

1.4.1 Metric Units—Grade = ¹/₁₀ of the minimum breaking force in kilonewtons divided by two times the nominal cross-sectional area in square millimeters. = (MBF)/(0.005)(π)(d)2

1.4.2 English Units—Grade = 0.000689 of the minimum breaking force in pounds divided by two times the nominal cross-sectional area in square inches. = (0.000689)(MBF)/(0.5)(π)(d)2

1.4.3 MBF = minimum breaking force (lb or kN); d = chain diameter (in. or mm).

Note 2: The above formulas are for round diameter links only. If different cross sections are used, the actual cross section of the link would need to be calculated and used.

1.5 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.