S-91138A915 0.218" ID x 0.5" OD ASME B18.21.1 Plastic Washers

Key Features & Benefits at a Glance

• Exceptional thermal stability with a wide operating range from -30°F to 450°F, ensuring reliable performance in extreme temperature environments
• Superior mechanical strength with Rockwell M114 hardness, providing excellent resistance to deformation under load
• Precision dimensional accuracy with 0.218" ID and 0.5" OD, ensuring perfect fit for No. 10 screws in inch-system assemblies
• Compliance with industry standards including ASME B18.21.1, guaranteeing consistent quality and interchangeability
• Environmental regulation compliance with RoHS 3 and REACH, making them safe for restricted substance-sensitive applications
• Outstanding chemical resistance inherent to Ultem PEI plastic material, protecting against corrosion and degradation
• Versatile thickness options ranging from 0.020" to 0.060", allowing customization for specific load distribution requirements

Professional Applications & Engineering Value

These Ultem PEI Plastic Flat Washers deliver critical engineering solutions for demanding industrial applications where conventional materials fail. The high-temperature resistance up to 450°F makes them ideal for aerospace, automotive, and electronics assemblies exposed to thermal cycling. Their chemical inertness prevents corrosion in harsh environments containing solvents, oils, and hydraulic fluids. The precision inch-system dimensions and ASME B18.21.1 compliance ensure seamless integration into existing No. 10 screw assemblies, eliminating compatibility issues. With Rockwell M114 hardness, these washers maintain dimensional stability under sustained compression loads, preventing fastener loosening in vibrating equipment. The combination of thermal endurance, mechanical strength, and regulatory compliance addresses the critical need for reliable plastic washers in regulated industries requiring both performance and safety certifications.

Specification Summary & Compliance

This Ultem PEI Plastic Flat Washer features precise dimensional specifications with 0.218" inner diameter, 0.5" outer diameter, and thickness ranging from 0.020" to 0.060" designed for No. 10 screw applications. Manufactured to ASME B18.21.1 standards for flat washers, ensuring dimensional consistency and mechanical performance. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming adherence to strict environmental and safety requirements for hazardous substances. The inch-system measurement ensures compatibility with North American industrial specifications and replacement part programs.