S-91128A378 1.062" ID Square Washers

Key Features & Benefits at a Glance

• Enhanced load distribution with a large 4" square surface area, preventing surface damage and loosening under high-stress conditions.
• Superior corrosion resistance from the black-oxide steel finish, extending service life in demanding industrial environments.
• Precise fit and secure fastening with a 1.062" inner diameter, engineered specifically for 1" screw sizes to ensure optimal performance.
• Exceptional mechanical strength due to the Rockwell 15N80 hardness, providing reliable performance in heavy-duty applications.
• Regulatory compliance assurance with RoHS 3 and REACH standards, ensuring safety and environmental responsibility for global supply chains.
• Durable material construction using inch-system steel, offering long-term reliability and resistance to wear and deformation.

Professional Applications & Engineering Value

This heavy-duty square washer is engineered to solve critical challenges in industrial assembly and construction. The black-oxide steel material provides a robust barrier against rust and corrosion, making it ideal for outdoor machinery, structural frameworks, and automotive applications where exposure to moisture and chemicals is common. Its 4" width and square shape significantly increase the bearing surface, distributing clamp load more effectively than standard washers. This design minimizes the risk of joint failure, material indentation, and bolt loosening under dynamic loads or vibrations. By specifying this washer for 1" screw fastening systems, engineers can enhance the longevity and safety of their assemblies, ensuring consistent performance in demanding environments like heavy equipment manufacturing and infrastructure projects.

Specification Summary & Compliance

This square washer features a 1.062" inner diameter and a thickness range of 0.235-0.265", manufactured to standard inch system tolerances for precise fit. It is made from black-oxide steel with a Rockwell 15N80 hardness rating, ensuring dimensional stability and strength. The product is fully compliant with RoHS 3 (2015/863/EU) under exemption 6(a) for lead in steel alloys and REACH (EC 1907/2006) regulations, meeting the latest SVHC requirements as of January 17, 2023.