S-91233A115 0.221" ID x 0.475" 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
• Enhanced durability with Rockwell C40 hardness, maintaining tooth integrity and locking performance in high-stress applications
• Reliable corrosion protection through black oxide steel finish, extending service life in industrial environments
• Precise dimensional fit with 0.221" ID and 0.475" OD, ensuring compatibility with No. 12 screws and consistent assembly
• Industry-standard compliance meeting ASME B18.21.1 specifications for guaranteed mechanical performance and interchangeability
• Environmental responsibility with RoHS 3 and REACH compliance, safe for regulated industries and global supply chains
• Optimized thickness range (0.020-0.027") providing flexibility while maintaining secure fastening under compression

Professional Applications & Engineering Value

These external tooth lock washers deliver critical vibration-dampening performance in demanding mechanical systems where loosening poses operational risks. The black oxide steel construction combines surface protection with the structural strength needed for repetitive stress cycles, while the external tooth configuration ensures maximum surface contact and bite. Engineered to ASME B18.21.1 standards, they provide reliable locking action in automotive assemblies, heavy machinery, electrical enclosures, and industrial equipment where inch system fasteners are specified. The precise internal diameter (0.221") and external teeth work synergistically to prevent both rotational slip and axial movement, solving common fastener failure points in high-vibration environments.

Specification Summary & Compliance

This No. 12 external tooth lock washer features dimensional specifications of 0.221" ID, 0.475" OD, and thickness ranging 0.020-0.027". Manufactured from black oxide steel with Rockwell C40 hardness, it conforms to ASME B18.21.1 mechanical standards for tooth lock washers. The product maintains full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring adherence to environmental and safety requirements for industrial components.