S-90251A539 1/4"-20 x 5/8" ASME B18.3 Set Screws
Set Screws
Image may differ from product. See technical specification for details.
Basic Information
Head Parameters
Dimensions
Thread Parameters
Tip & Drive Parameters
Material & Strength
Temperature & Environment
- Fast delivery
- Enjoy discounts on bulk purchases
- Secure Payment
- Fast Global Shipping
Key Features & Benefits at a Glance
- Permanent vibration resistance with nylon patch thread locker that maintains secure fastening under dynamic loads
- Superior corrosion protection from 18-8 stainless steel construction for extended service life in harsh environments
- Precision Class 3A thread fit ensures consistent engagement and reliable torque transmission in critical assemblies
- High-temperature capability with thread locker performance maintained from -50° to 250°F for demanding applications
- Space-saving headless design allows flush mounting where protruding fasteners are impractical
- Enhanced installation control through hex drive design providing positive torque application
- Industry-standard compliance with ASME B18.3 specifications for guaranteed dimensional accuracy
Professional Applications & Engineering Value
This 18-8 stainless steel hex headless set screw delivers exceptional engineering value in applications where vibration resistance and space constraints are critical concerns. The permanent nylon patch thread locker embedded in the UNC threads creates a chemical bond that prevents loosening under continuous stress, eliminating the need for secondary locking mechanisms. The corrosion-resistant properties of 18-8 stainless steel make it ideal for harsh environments including marine, chemical processing, and outdoor equipment. The headless design with hex drive provides reliable torque transmission while maintaining a flush surface profile, perfect for securing collars, gears, and pulleys on shafts in machinery, automotive, and aerospace assemblies where precision alignment and minimal protrusion are essential.
Specification Summary & Compliance
Manufactured to exact Class 3A thread fit tolerances with UNC 1/4"-20 coarse threading for optimal engagement in industrial applications. This set screw conforms to ASME B18.3 dimensional standards and demonstrates full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. The Rockwell B80 hardness rating ensures durability while maintaining necessary toughness for repeated installation cycles in precision assemblies.
