S-91309A581 5/16"-18 x 3/4" ASME B18.2.1, ASTM A307 Low-Strength Steel Hex Head Screws
Low-Strength Steel Hex Head 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 zinc plating, extending service life in demanding industrial environments
- High tensile strength of 60,000 psi ensures reliable performance under heavy loads and vibration
- Rockwell B69 hardness provides excellent durability and resistance to wear and deformation
- Class 2A thread fit with UNC coarse threading enables quick assembly and secure fastening in various materials
- External hex drive design allows for high-torque installation with standard tools, reducing assembly time
- Full threading along the 3/4" length offers maximum grip and adjustment flexibility in applications
- Compliance with major industry standards including ASME B18.2.1 and ASTM A307 guarantees consistent quality and performance
Professional Applications & Engineering Value
These 5/16"-18 UNC hex head screws deliver exceptional engineering value in industrial fastening applications where reliability is critical. The steel construction with zinc plating provides robust protection against corrosion, making them ideal for machinery, structural assemblies, and equipment exposed to harsh conditions. The coarse UNC threading ensures superior grip in soft materials and prevents cross-threading during installation, while the external hex drive facilitates high-torque applications without stripping. With full threading across the entire 3/4" length, these screws maintain consistent clamping force in thick materials and vibration-prone environments, solving common loosening issues in heavy-duty applications.
Specification Summary & Compliance
Manufactured to precise Class 2A thread fit tolerances with UNC coarse thread specifications, these hex head screws meet ASME B18.2.1 dimensional requirements and ASTM A307 material standards. Compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations ensures environmental responsibility and workplace safety. The inch system measurements guarantee compatibility with North American industrial equipment and replacement part requirements.
