S-91381A391 1/4"-28 x 3/4" 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
- Non-marring brass tip prevents damage to delicate surfaces while maintaining secure fastening
- Precise Class 3A thread fit ensures superior engagement and vibration resistance in critical applications
- Black-oxide alloy steel construction provides excellent corrosion resistance and durability
- Rockwell C28 hardness rating delivers optimal strength and wear resistance for long service life
- Headless hex drive design allows for flush installation in confined spaces with easy 1/8" hex key access
- Fine UNF thread configuration offers enhanced clamping force and superior holding power
- Full regulatory compliance meets ASME B18.3 standards and environmental requirements (RoHS 3 & REACH)
Professional Applications & Engineering Value
This black-oxide alloy steel set screw with brass soft tip addresses critical engineering challenges in precision assembly applications. The unique brass tip material eliminates surface damage on shafts, gears, and collars while maintaining secure positioning, making it ideal for precision equipment and machinery components where surface integrity is paramount. The Class 3A UNF thread fit provides exceptional dimensional accuracy for vibration-resistant fastening in high-stress environments. The headless hex drive design enables seamless integration in space-constrained applications while the black-oxide surface treatment enhances corrosion resistance in industrial settings. Engineered for set screw applications requiring both reliability and surface protection.
Specification Summary & Compliance
This precision fastener features 1/4"-28 UNF fine threads with Class 3A thread fit for superior dimensional accuracy and engagement. Manufactured to ASME B18.3 specifications with Rockwell C28 hardness rating. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring safe use across various industrial applications. The right-hand thread direction and 3/4" length provide standardized installation compatibility.
