S-95348A121 20.95 mm ID x 40.64 mm OD ASME B18.2.6M; ASTM F959 Tension-Indicating Structural Washers

Key Features & Benefits at a Glance

• Precise Load Verification: Orange tension-indicating dye provides immediate visual confirmation of proper bolt tension, eliminating guesswork and ensuring correct installation.
• Exceptional Strength & Reliability: Class 10.9 material grade delivers high tensile strength and dependable performance under extreme loads up to 179,000 N.
• Superior Corrosion Resistance: Zinc-plated steel construction offers enhanced protection against rust and environmental degradation, extending service life.
• Optimized for M20 Bolts: Precisely engineered with a 20.95 mm ID and 40.64 mm OD for a perfect fit and optimal load distribution on M20 fasteners.
• Consistent Hardness & Durability: Rockwell C37 hardness ensures the washer maintains its shape and function, preventing deformation under high stress.
• Guaranteed Compliance & Quality: Manufactured to meet ASME B18.2.6M and ASTM F959 standards, ensuring dimensional accuracy and performance reliability.
• Environmentally Responsible: Compliant with RoHS 3 and REACH regulations, making them suitable for use in regulated industries and global markets.

Professional Applications & Engineering Value

This M20 Class 10.9 tension indicating washer is engineered to solve critical challenges in heavy-duty industrial applications where precise bolt preload is essential for structural integrity. The zinc-plated steel construction provides excellent corrosion resistance, making it ideal for outdoor construction, machinery, and infrastructure projects exposed to harsh environments. The innovative orange tension-indicating dye offers a reliable, visual method for verifying that the specified 179,000 N tension is achieved, reducing the risk of joint failure due to under or over-tightening. By integrating this tension indicating system, engineers and maintenance teams can ensure consistent clamping force, enhance safety, and minimize downtime in mechanical fastening assemblies, from bridges and towers to heavy equipment and industrial plants.

Specification Summary & Compliance

This washer features precise dimensions with an ID of 20.95 mm, OD of 40.64 mm, and a thickness range of 3.600mm to 6.000mm, designed for M20 screw sizes. It is manufactured to meet ASME B18.2.6M and ASTM F959 specifications, ensuring consistent performance and dimensional accuracy. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming its suitability for use in environmentally conscious and regulated markets.