S-98970A231 1.75" ID x 4" OD Oversized Washers

Key Features & Benefits at a Glance

• Superior corrosion resistance from hot-dipped galvanized steel coating, extending service life in harsh industrial environments.
• Enhanced load distribution with a large 4" outer diameter, minimizing surface pressure and preventing material damage.
• Precise compatibility with 1 1/2" screw sizes, ensuring secure fastening and reducing assembly errors.
• Exceptional durability backed by Rockwell B40 hardness, maintaining structural integrity under heavy loads.
• Reliable thickness tolerance (0.302-0.332") for consistent performance and ease of installation in mechanical assemblies.
• Compliance with strict regulations including RoHS 3 and REACH, ensuring safe use in regulated industries.
• Robust construction in inch measurement system, ideal for North American industrial standards and replacement parts.

Professional Applications & Engineering Value

This hot-dipped galvanized steel flat washer is engineered to address critical challenges in industrial fastening applications, such as structural bolting, heavy machinery, and outdoor equipment. The zinc coating provides a sacrificial layer that combats rust and corrosion, significantly prolonging fastener life in humid or chemically exposed settings. With its generous 4" OD and 1.75" ID, it effectively distributes clamping force over a wider area, preventing joint loosening and surface indentation on soft materials. The Rockwell B40 hardness ensures the washer resists deformation under sustained vibration or dynamic loads, making it a dependable choice for high-stress mechanical assemblies where reliability is non-negotiable.

Specification Summary & Compliance

This flat washer conforms to standard inch dimensional tolerances with an inner diameter of 1.75", outer diameter of 4", and thickness ranging from 0.302" to 0.332". It is manufactured from hot-dipped galvanized steel and is designed for use with 1 1/2" screw sizes. The product is RoHS 3 (2015/863/EU) compliant under exemption 6(a) for lead in steel alloys and REACH (EC 1907/2006) compliant as of January 17, 2023, meeting current environmental and safety standards for industrial components.