S-91860A031 0.438" ID x 1" OD ASME B18.21.1 General Purpose Washers

Key Features & Benefits at a Glance

• Superior corrosion resistance from 17-7 PH stainless steel construction for extended service life in harsh environments
• Exceptional hardness with Rockwell C40 rating to prevent deformation under heavy loads and repeated use
• Precise dimensional fit with 1" OD and 0.438" ID specifically engineered for 3/8" screw applications
• Industry-standard compliance with ASME B18.21.1 specifications ensuring reliable performance and interchangeability
• Environmental responsibility through RoHS 3 and REACH compliance for safe use in regulated industries
• Optimized load distribution with 0.073-0.083" thickness range to protect surfaces and prevent fastener loosening
• Durable performance in inch measurement system applications requiring consistent, long-lasting mechanical protection

Professional Applications & Engineering Value

These 17-7 PH stainless steel flat washers deliver critical engineering solutions where corrosion resistance and structural integrity are paramount. The precipitation-hardening stainless steel composition maintains exceptional strength in high-stress environments, while the precise 1" OD x 0.438" ID dimensions ensure perfect compatibility with 3/8" screw sizes. Industrial applications benefit from their ability to prevent galvanic corrosion, distribute clamping forces evenly across joint surfaces, and maintain Rockwell C40 hardness under vibration and thermal cycling. These heavy-duty flat washers are engineered for machinery, structural assemblies, and equipment exposed to chemicals, moisture, or extreme temperatures where standard washers would fail prematurely.

Specification Summary & Compliance

This flat washer features inch system dimensions with 1" outer diameter, 0.438" inner diameter, and thickness range of 0.073-0.083". Manufactured to ASME B18.21.1 standards for dimensional consistency and mechanical properties. The 17-7 PH stainless steel construction provides Rockwell C40 hardness for superior wear resistance. Full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations ensures environmental safety and unrestricted use across global markets.