S-91138A850 0.343" ID x 0.688" OD ASME B18.21.1 Plastic Washers

Key Features & Benefits at a Glance

• Exceptional high-temperature performance with a broad operating range from -30°F to 450°F, ensuring reliable function in extreme thermal environments
• Superior chemical resistance thanks to Ultem PEI plastic material, protecting against corrosion and degradation in harsh industrial settings
• Enhanced durability and load distribution with Rockwell M114 hardness, reducing wear and extending service life of assemblies
• Precise dimensional fit with 5/16" screw size compatibility and consistent 0.343" ID/0.688" OD, ensuring secure fastening and alignment
• Compliance with industry standards including ASME B18.21.1, guaranteeing consistent quality and interchangeability
• Environmental and safety compliance with RoHS 3 and REACH regulations, making them suitable for regulated industries
• Reliable thickness tolerance between 0.060-0.100", providing consistent performance in various compression applications

Professional Applications & Engineering Value

These Ultem PEI plastic flat washers are engineered to solve critical challenges in demanding industrial environments where traditional metal washers fail. The high-temperature rating of 450°F makes them ideal for automotive, aerospace, and electronics applications involving thermal cycling and heat exposure. Their exceptional chemical resistance prevents degradation from oils, solvents, and cleaning agents, maintaining integrity in chemical processing and manufacturing equipment. The black color provides UV stability for outdoor applications, while the inch system measurement ensures compatibility with North American machinery and standards. These washers deliver reliable performance in electrical insulation applications, food processing equipment, and precision assemblies where dimensional stability and regulatory compliance are paramount.

Specification Summary & Compliance

These flat washers feature precise dimensional specifications with 0.343" ID, 0.688" OD, and thickness range of 0.060-0.100" for consistent performance. Manufactured to ASME B18.21.1 standards for dimensional accuracy and quality assurance. The washers are fully RoHS 3 (2015/863/EU) compliant and REACH (EC 1907/2006) compliant with current SVHC requirements as of January 2022, ensuring environmental safety and regulatory adherence for global industrial applications.