S-90289A109 4-40 x 3/8" ASME B18.3 Set Screws
Set Screws
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Basic Information
Head Parameters
Dimensions
Thread Parameters
Tip & Drive Parameters
Material & Strength
Temperature & Environment
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Key Features & Benefits at a Glance
- Superior corrosion resistance with black-oxide coating on alloy steel for extended service life in demanding environments
- Maximum holding power achieved through Class 3A thread fit precision and serrated locking mechanism
- Exceptional durability with Rockwell C45 hardness maintaining structural integrity under high stress
- Secure installation enabled by hex drive design and cup tip for concentrated contact pressure
- Reliable coarse threading (UNC) providing faster assembly and reduced cross-threading risks
- Space-saving headless design allowing flush mounting in confined applications
- Industry compliance assurance meeting ASME B18.3 specifications for consistent performance
Professional Applications & Engineering Value
This 4-40 UNC set screw delivers critical engineering solutions for precision assemblies requiring secure component positioning. The black-oxide alloy steel construction provides essential corrosion protection while maintaining Rockwell C45 hardness for vibration resistance in machinery, automotive, and aerospace applications. The combination of hex drive and cup tip ensures maximum torque transmission and localized clamping force, preventing shaft slippage in pulleys, gears, and collars. Class 3A thread fit with coarse UNC threading maintains dimensional stability under thermal cycling, while serrations create positive mechanical locking against rotational forces. These features make it ideal for permanent installations where disassembly isn't anticipated, providing reliable performance in high-stress industrial environments.
Specification Summary & Compliance
Manufactured to precise Class 3A thread fit tolerances with 4-40 UNC coarse threads and 0.112" thread diameter. Complies with ASME B18.3 dimensional standards and meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. Features right-hand thread direction, 3/8" length, and 0.050" hex drive size for consistent performance across industrial applications.
