S-91138A857 0.469" ID x 1.25" OD ASME B18.21.1 Plastic Washers

Key Features & Benefits at a Glance

• Exceptional high-temperature resistance maintains structural integrity from -30°F to 450°F, ideal for extreme thermal cycling environments
• Superior Rockwell M114 hardness delivers outstanding wear resistance and long-term dimensional stability under load
• Precision-engineered dimensions (1.25" OD x 0.469" ID) ensure perfect fit for 7/16" screws, preventing misalignment and assembly issues
• Chemical-resistant Ultem PEI material provides excellent performance in harsh industrial environments and corrosive applications
• Full regulatory compliance with RoHS 3 and REACH standards eliminates supply chain restrictions and environmental concerns
• ASME B18.21.1 specification compliance guarantees consistent quality and interchangeability in industrial applications
• Lightweight plastic construction reduces overall assembly weight while providing electrical insulation properties

Professional Applications & Engineering Value

Engineered for demanding environments where metal washers fail, this Ultem PEI plastic flat washer solves critical thermal management challenges in aerospace, automotive, and electronics assemblies. The high-temperature rating (450°F maximum) prevents deformation in engine compartments and electrical enclosures, while the Rockwell M114 hardness ensures reliable performance under vibration and constant pressure. As an inch system washer meeting ASME B18.21.1 specifications, it provides precise spacing and load distribution for 7/16" screws in manufacturing equipment, chemical processing systems, and food machinery where corrosion resistance and regulatory compliance are mandatory. The black color offers UV stability for outdoor applications.

Specification Summary & Compliance

This flat washer features precision dimensions: 1.25" OD, 0.469" ID, and thickness range of 0.051-0.080". Manufactured to ASME B18.21.1 standards for dimensional consistency and performance reliability. Fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and global market acceptance. The Ultem PEI material delivers consistent performance across the specified temperature range of -30°F to 450°F with maintained Rockwell M114 hardness.