S-98438A033 0.513" ID x 0.9" OD ASME B18.21.1 External-Tooth Lock Washers

Key Features & Benefits at a Glance

• Superior vibration resistance with external teeth design that bites into mating surfaces to prevent loosening under dynamic loads
• Exceptional corrosion resistance from 400 Series Stainless Steel construction for long-term reliability in harsh environments
• Optimized dimensional accuracy with 0.513" ID and 0.9" OD ensuring perfect fit for 1/2" screw applications
• Enhanced mechanical strength with Rockwell C34 hardness providing excellent wear resistance and load distribution
• Industry-standard compliance meeting ASME B18.21.1 specifications for consistent performance and interchangeability
• Environmental regulation adherence with RoHS 3 and REACH compliance for safe use in regulated industries
• Reliable thickness control between 0.037-0.045" for consistent clamping force and assembly performance

Professional Applications & Engineering Value

This external tooth lock washer delivers critical vibration-resistant performance in demanding industrial environments where fastener security is paramount. Engineered from 400 Series Stainless Steel, it provides excellent corrosion resistance while maintaining mechanical integrity in applications exposed to moisture, chemicals, or temperature variations. The precisely positioned external teeth create multiple biting points that dig into both the fastener head and mounting surface, effectively preventing rotational loosening caused by machinery vibration, impact loads, or thermal cycling. This design makes it particularly valuable for heavy-duty equipment, automotive assemblies, industrial machinery, and construction applications where reliable locking performance directly impacts operational safety and maintenance intervals. The combination of material strength, precise tooth geometry, and standardized dimensions ensures consistent performance across production runs and replacement scenarios.

Specification Summary & Compliance

This tooth lock washer features inch system dimensions with 0.513" internal diameter and 0.9" outer diameter, specifically engineered for 1/2" screw applications. Manufactured to ASME B18.21.1 standards, it ensures dimensional interchangeability and performance reliability. The 400 Series Stainless Steel construction provides Rockwell C34 hardness for optimal mechanical properties. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, meeting the latest environmental and safety requirements for industrial components.