S-97345A821 1/2"-13 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 Stainless Steel construction, ideal for harsh industrial environments and extended service life.
• Exceptional mechanical strength offering 70,000 psi tensile strength and 35,000 psi minimum shear strength for reliable performance under high stress.
• Precise alignment and location ensured by the standard shoulder fit and controlled diameter/length tolerances for consistent assembly.
• Secure and easy installation with a knurled socket head and 3/8" hex drive, providing excellent grip and torque transmission.
• High thread reliability with a Class 3A fit and coarse 1/2"-13 UNC thread, enabling quick assembly and vibration resistance.
• Compliance with industry standards including ASME B18.3, RoHS 3, and REACH, ensuring quality and environmental safety for global applications.
• Durable and wear-resistant material with a Rockwell B79 hardness, maintaining integrity in demanding mechanical uses.

Professional Applications & Engineering Value

This 316 Stainless Steel shoulder screw is engineered to address critical challenges in precision machinery, automation systems, and heavy-duty equipment. The 1/2"-13 UNC coarse thread with Class 3A fit ensures fast, secure fastening while minimizing the risk of cross-threading, which is vital for high-volume production lines. The knurled socket head design enhances grip during installation, reducing tool slippage and improving operator safety. With its robust 70,000 psi tensile strength and excellent corrosion resistance, this screw reliably supports rotating parts, linkages, and pivots in environments exposed to moisture, chemicals, or extreme temperatures. Its compliance with ASME B18.3 and environmental regulations makes it a trusted choice for OEMs and MRO applications requiring consistent performance and longevity.

Specification Summary & Compliance

This shoulder screw adheres to precise dimensional standards, including a Class 3A thread fit for tight tolerances and a standard shoulder fit with diameter tolerance of -0.004" to -0.002" and length tolerance of -0.005" to 0.005". It conforms to ASME B18.3 specifications and is compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006), ensuring it meets rigorous industry and environmental safety requirements for global use.