S-98438A030 0.32" ID x 0.61" OD ASME B18.21.1 External-Tooth Lock Washers

Key Features & Benefits at a Glance

• Superior vibration resistance with external teeth that bite into mating surfaces, preventing loosening under dynamic loads
• Exceptional corrosion resistance from 400 Series Stainless Steel construction, ideal for harsh industrial environments
• Maximum locking force maintained through Rockwell C34 hardness, ensuring long-term fastener security
• Precision dimensional control with 0.32" ID and 0.61" OD for perfect fit with 5/16" fasteners
• Industry-standard compliance with ASME B18.21.1 specifications for reliable performance in critical applications
• Environmental responsibility through RoHS 3 and REACH compliance, meeting strict regulatory requirements
• Optimized thickness range (0.028-0.034") providing consistent compression and spring action

Professional Applications & Engineering Value

This external tooth lock washer delivers critical vibration-resistant performance in demanding industrial settings where fastener security is paramount. Engineered from 400 Series Stainless Steel, it provides excellent corrosion resistance for applications exposed to moisture, chemicals, or outdoor elements. The external tooth configuration creates multiple biting points that dig into both the fastener and mounting surface, effectively resisting rotational forces and vibration-induced loosening. This makes it ideal for heavy machinery, automotive assemblies, electrical enclosures, and structural frameworks where maintaining bolt tension is critical to operational safety and equipment longevity. The combination of Rockwell C34 hardness and precise dimensional control ensures consistent performance across production runs, reducing maintenance intervals and preventing costly downtime.

Specification Summary & Compliance

This 5/16" external tooth lock washer features precise dimensional specifications including 0.32" inner diameter, 0.61" outer diameter, and thickness ranging from 0.028" to 0.034". Manufactured to ASME B18.21.1 standards for tooth lock washers, it ensures consistent quality and performance in inch system applications. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, meeting current environmental safety requirements for industrial components. The 400 Series Stainless Steel construction with Rockwell C34 hardness provides the optimal balance of strength and corrosion resistance for demanding fastener applications.