Mechanical and Material Requirements for SAE J429 Externally Threaded Fasteners

The SAE J429 standard, developed by the Society of Automotive Engineers (SAE), describes the mechanical and material requirements for inch series steel bolts, screws, studs, screws for sems, and U-bolts in sizes including 1-1/2 inches.

The term stud referred to in this standard refers to a cylindrical rod of medium length with threads at one or both ends or along its entire length. Heads, collars or similar products characterized more closely by the requirements for bolts shown here are not covered by this standard.

The mechanical properties given in Table 1 in the standard were compiled at an ambient temperature of approximately 20 degrees. These properties apply over a temperature range that depends on the quality of the material used and the thermal and mechanical processing. Fatigue behavior, corrosion resistance, impact properties and other properties such as these are beyond the scope of this standard.

The test methods defined in the framework of the SAE J429 standard are:

• Hardness test: The hardness of bolts, screws, studs and rings is determined at the mid-radius of the cross-section along the threaded portion of the product taken one diameter away from the end of the product. Reported hardness is the average of four hardness readings placed at 90 degrees to each other.
• Surface hardness testing: Tests to determine surface hardness conditions are performed on prepared tips, hexagonal flats, or unthreaded shanks with light grinding or polishing to provide accurate repeatable readings according to the SAE J417 standard. According to ASTM E 18 standard, when hardness tests are performed on curved surfaces, appropriate correction factors should be used.
• Arbitrator tempering temperature test: In a dispute regarding the tempering temperature, the following procedure is used for arbitrator purposes: hardness testing is performed on one or more bolts, screws or studs from the batch, the products are at nominal diameter at a temperature 6,7 degrees lower than the specified minimum annealing temperature Re-tempered for a minimum of 1,0 minutes but not less than 30 minutes for every 30, the product hardness test is repeated.

Among the numerous test, measurement, analysis and evaluation studies it provides for businesses in various sectors, our organization also provides testing services for mechanical and material requirements for external threaded fasteners, within the scope of SAE J429 standard, with its trained and expert staff and advanced technological equipment.