S-91259A492 3/8"-16 ASME B18.3, ASTM A574 Shoulder Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with 140,000 psi tensile strength for reliable performance in demanding industrial applications
• Superior corrosion resistance through black oxide finish, extending service life in harsh operating environments
• Precision Class 3A thread fit ensures secure fastening and vibration resistance in critical assemblies
• Knurled socket head design provides enhanced grip and prevents slipping during installation and maintenance
• Accurate shoulder positioning with 1/2" diameter and tight tolerances for precise component alignment
• High hardness rating of Rockwell C32 maintains dimensional stability under heavy mechanical stress
• Comprehensive compliance with ASME B18.3, RoHS 3, and REACH standards for quality assurance and environmental safety

Professional Applications & Engineering Value

This alloy steel shoulder screw with black oxide finish delivers exceptional engineering value in precision machinery and industrial equipment. The 3/8"-16 UNC coarse threads with Class 3A fit provide superior vibration resistance and reliable fastening in high-stress applications. The precisely machined 1/2" shoulder diameter serves as an accurate locating surface for rotating components, bearings, and linkages, eliminating the need for additional spacers or bushings. The knurled socket head with 1/4" hex drive ensures secure tool engagement during installation in confined spaces. Engineered for industrial shoulder screw applications requiring both structural integrity and corrosion protection, this component solves critical alignment and durability challenges in automotive, aerospace, and heavy machinery assemblies.

Specification Summary & Compliance

This precision shoulder screw features Class 3A thread fit with tight tolerances on both shoulder diameter (-0.004" to -0.002") and shoulder length (-0.005" to 0.005"). Manufactured to ASME B18.3 specifications using ASTM A574 alloy steel, it ensures dimensional accuracy and mechanical reliability. The component is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, making it suitable for global industrial applications requiring strict material safety standards.