S-91247A030 1/4"-28 x 4 1/2" ASME B18.2.1, SAE J429 Medium-Strength Grade 5 Steel Hex Head Screws
Medium-Strength Grade 5 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
- High tensile strength of 120,000 psi ensures reliable performance under heavy loads and vibrations in demanding industrial environments.
- Zinc plating provides a protective barrier against corrosion, extending the fastener's service life in various operating conditions.
- Grade 5 classification and Rockwell C25 hardness guarantee consistent strength and durability, reducing the risk of fastener failure.
- UNF fine thread and Class 2A fit offer superior vibration resistance and precise engagement for secure fastening in critical assemblies.
- Partially threaded design concentrates clamping force where needed, improving joint integrity and preventing loosening.
- External hex drive and hex head allow for easy installation and high torque application with standard tools, speeding up assembly processes.
- Compliance with ASME B18.2.1, RoHS 3, and REACH ensures product quality, safety, and environmental responsibility for global supply chains.
Professional Applications & Engineering Value
This Grade 5 hex head screw is engineered to solve common industrial challenges such as joint failure and corrosion. The zinc plated steel construction resists rust in humid or outdoor settings, while the 1/4"-28 UNF fine thread maintains tightness under dynamic loads, making it ideal for machinery, automotive frames, and structural supports. Its partially threaded shank ensures that the unthreaded portion bears against materials, providing maximum clamping force and reducing stress concentration. By meeting ASME B18.2.1 standards, it delivers predictable performance in heavy-duty applications, minimizing downtime and maintenance costs for engineers and procurement teams.
Specification Summary & Compliance
This fastener adheres to precise dimensional tolerances, including a Class 2A thread fit for consistent engagement and UNF fine threading per industry norms. It conforms to ASME B18.2.1 and SAE J429 specifications for Grade 5 bolts, ensuring mechanical properties like tensile strength and hardness. Additionally, it is RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, supporting environmental and safety regulations in industrial supply chains.
