S-90298A801 1/2"-13 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel and passivated finish, ideal for harsh industrial environments
• Enhanced durability and wear resistance from Rockwell B55 hardness, ensuring long service life under heavy loads
• Precise thread engagement and vibration resistance due to Class 3A thread fit and 1/2"-13 UNC coarse threads
• Accurate alignment and reduced assembly play with a shoulder diameter tolerance of ±0.001" and shoulder length tolerance of ±0.005"
• Secure, non-slip installation featuring a knurled hex socket head and 5/16" hex drive for reliable torque application
• Compliance with industry standards including ASME B18.3, RoHS 3, and REACH for safe, regulated use
• Versatile heavy-duty performance with a 1 3/4" shoulder length and standard shoulder fit for various mechanical applications

Professional Applications & Engineering Value

This 18-8 stainless steel shoulder screw is engineered to address critical challenges in precision machinery, automation systems, and heavy equipment. The passivated finish provides exceptional corrosion resistance, reducing maintenance in humid or chemically exposed settings. Its Class 3A thread fit and UNC coarse threads ensure tight, reliable fastening that resists loosening under vibration, common in conveyor systems or robotic arms. The precisely machined shoulder, with tight diameter and length tolerances, allows for accurate component alignment, minimizing wear and extending the life of rotating parts like bearings and pulleys. The knurled hex socket head enables secure tool engagement, preventing slippage during high-torque installations. Ideal for use in industrial shoulder bolt applications, this screw supports efficient assembly and long-term operational stability.

Specification Summary & Compliance

This shoulder screw adheres to ASME B18.3 specifications, ensuring dimensional accuracy and performance reliability. Threads are manufactured to Class 3A fit with 1/2"-13 UNC coarse thread spacing, while the shoulder features a diameter tolerance of -0.001" to 0.001" and length tolerance of -0.005" to 0.005". The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming it is free of hazardous substances and safe for various industrial and international markets.