S-90251A541 1/4"-20 x 1" ASME B18.3 Set Screws

Key Features & Benefits at a Glance

• Superior vibration resistance with a nylon patch locking feature that prevents loosening under dynamic loads
• Excellent corrosion resistance due to 18-8 stainless steel construction, ideal for harsh industrial environments
• Precise thread engagement with Class 3A UNC coarse threads ensuring reliable, secure fastening
• High durability and strength backed by Rockwell B80 hardness for long-term performance in demanding applications
• Wide temperature tolerance from -70° to 250°F, maintaining integrity in varied operating conditions
• Easy installation and removal with a hex drive style and headless design for space-constrained assemblies
• Enhanced grip and positioning from the cup tip, minimizing component slippage during torque application

Professional Applications & Engineering Value

This nylon patch locking set screw is engineered to address critical challenges in industrial assemblies where vibration-induced loosening can compromise safety and performance. The 18-8 stainless steel material provides inherent corrosion resistance, making it suitable for outdoor, marine, or chemical-exposed environments. With a Class 3A UNC thread fit and coarse spacing, it delivers rapid installation and high clamp force retention in components like shafts, pulleys, and gears. The hex headless design allows for flush mounting in tight spaces, while the nylon patch thread locker ensures consistent torque hold without requiring additional adhesives. Ideal for machinery, automotive, and aerospace applications, this fastener enhances assembly reliability and reduces maintenance frequency.

Specification Summary & Compliance

This set screw features a 1/4"-20 UNC thread with Class 3A precision tolerance and coarse thread spacing for optimal engagement. It complies with ASME B18.3 manufacturing standards and meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring safe and sustainable use in global markets.