S-91247A028 1/4"-28 x 4" ASME B18.2.1, SAE J429 Medium-Strength Grade 5 Steel Hex Head Screws
Medium-Strength Grade 5 Steel Hex Head 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
- Superior tensile strength of 120,000 psi ensures reliable performance in high-stress applications, reducing the risk of fastener failure.
- Excellent corrosion resistance from zinc plating extends service life in harsh or outdoor industrial environments.
- Precise UNF fine threading provides better engagement and vibration resistance in critical assemblies compared to coarse threads.
- High hardness rating (Rockwell C25) offers exceptional wear resistance and durability under repeated use.
- Class 2A thread fit ensures consistent, easy assembly while maintaining secure fastening without galling.
- Partial threading design allows for controlled clamping force and improved shear strength in specific joint configurations.
- Compliance with major standards including ASME B18.2.1 guarantees interchangeability and reliability in regulated applications.
Professional Applications & Engineering Value
This Grade 5 hex head screw is engineered to address common industrial challenges such as joint integrity under dynamic loads and environmental degradation. The zinc-plated steel construction provides a protective barrier against corrosion, making it ideal for machinery, structural frames, and outdoor equipment where moisture exposure is a concern. The UNF fine thread offers superior resistance to loosening from vibration, a critical advantage in automotive, aerospace, and heavy machinery applications. With partial threading, it ensures that the unthreaded shank bears shear loads effectively, while the threaded portion delivers optimal clamping force. Meeting ASME B18.2.1 specifications, this fastener provides consistent performance and compatibility in demanding engineering projects, reducing downtime and maintenance costs.
Specification Summary & Compliance
This fastener adheres to Class 2A thread fit tolerances for consistent assembly and is manufactured in accordance with ASME B18.2.1 and SAE J429 standards. It is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it meets environmental and safety requirements for industrial use worldwide.
