S-97832A312 1/4"-20 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Corrosion-resistant performance with 18-8 Stainless Steel construction, ideal for harsh industrial environments and washdown applications.
• Precise component alignment and pivot points enabled by the 1 1/8" shoulder with controlled diameter tolerance for consistent assembly.
li>Superior torque transmission and reduced tool slippage from the knurled socket head and 5/32" hex drive for reliable fastening.
• High mechanical strength and durability with 70,000 psi tensile strength and Rockwell B55 hardness for demanding, high-stress applications.
• Secure, vibration-resistant thread engagement due to the Class 3A thread fit and 1/4"-20 UNC coarse thread for quick assembly.
• Compliance with industry standards including ASME B18.3, ensuring dimensional accuracy and interchangeability in professional settings.
• Environmental and safety compliance with RoHS 3 and REACH standards, making it suitable for regulated industries.

Professional Applications & Engineering Value

This shoulder screw is engineered to address critical alignment and pivot challenges in machinery and assemblies. The 18-8 Stainless Steel material provides excellent corrosion resistance, extending service life in environments exposed to moisture, chemicals, or outdoor elements. The precision-machined shoulder acts as a reliable bearing surface or spacer, minimizing wear on moving parts and ensuring accurate positioning in industrial applications like linkages, gears, and rotating assemblies. The Class 3A thread fit and UNC coarse thread facilitate rapid installation while maintaining a secure hold, reducing the risk of loosening under vibration. Combined with the knurled socket head for enhanced grip during torque application, this screw delivers consistent performance in high-load scenarios, from automotive jigs to packaging equipment.

Specification Summary & Compliance

This shoulder screw features a 1/4"-20 UNC coarse thread with a Class 3A thread fit for precise, secure fastening. The shoulder diameter is 5/16" with a tolerance of -0.004" to -0.002", and the shoulder length is 1 1/8" with a tolerance of -0.005" to 0.005", ensuring dimensional accuracy per ASME B18.3 specifications. It is manufactured from 18-8 Stainless Steel with a hardness of Rockwell B55, tensile strength of 70,000 psi, and minimum shear strength of 35,000 psi. The product is compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations.