S-97345A649 1/4"-20 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance in harsh environments thanks to 316 Stainless Steel construction, ideal for chemical, marine, and outdoor applications.
• Exceptional mechanical strength with 70,000 psi tensile and 35,000 psi shear strength, ensuring reliable performance under high-stress conditions.
• Precise Class 3A thread fit for secure, vibration-resistant assemblies, reducing the risk of loosening in dynamic applications.
• Easy installation and removal with a hex socket drive and knurled head, providing a firm grip and reducing tool slippage.
• Durable shoulder design with a 3/8" diameter and controlled tolerances, offering stable alignment and bearing surfaces for rotating parts.
• Compliance with industry standards including ASME B18.3, RoHS 3, and REACH, ensuring safety and environmental responsibility.
• Coarse 1/4"-20 UNC threads enable quick assembly and are less prone to clogging in dirty or debris-filled environments.

Professional Applications & Engineering Value

This 316 Stainless Steel shoulder screw is engineered to address critical challenges in industrial settings, such as corrosion from chemicals or moisture, and mechanical stress from constant motion. The Class 3A thread fit and coarse UNC threads provide a tight, reliable connection that resists vibration and wear, making it ideal for machinery, automotive assemblies, and precision equipment. The knurled head and hex socket drive simplify maintenance, while the shoulder diameter acts as a pivot or spacer, reducing friction and misalignment. With high tensile and shear strength, it ensures long-term durability in demanding applications like conveyor systems or robotic arms, where failure is not an option.

Specification Summary & Compliance

This shoulder screw adheres to Class 3A thread fit tolerances for precise engagement, with a 1/4"-20 UNC coarse thread and 3/4" thread length. The shoulder features a diameter of 3/8" with tight tolerances (-0.004" to -0.002") and length of 13/16" (±0.005"). It meets ASME B18.3 specifications for dimensional consistency and is RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliant, ensuring it is free from hazardous substances for safe industrial use.