S-92186A331 1/4"-28 x 3 1/2" ASME B18.2.1 Super-Corrosion-Resistant 316 Stainless Steel Hex Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 stainless steel construction, ideal for harsh environments and chemical exposure
• High mechanical strength with 70,000 psi tensile strength and Rockwell B70 hardness for reliable load-bearing performance
• Precise thread engagement through Class 2A thread fit and UNF fine threading, ensuring secure fastening and vibration resistance
• Easy installation and removal with external hex head design (7/16" width) for standard tool compatibility
• Optimized partial threading (3/4" min thread length) providing strong grip while reducing material usage
• Industry-standard compliance meeting ASME B18.2.1 specifications for dimensional accuracy and performance
• Environmental responsibility with RoHS 3 and REACH compliance, safe for regulated applications

Professional Applications & Engineering Value

This 1/4"-28 UNF hex head screw in 316 stainless steel delivers exceptional performance in demanding industrial settings where corrosion resistance and mechanical integrity are critical. The fine thread spacing and Class 2A thread fit provide superior vibration resistance and precise clamping force distribution, making it ideal for machinery assembly, marine equipment, chemical processing systems, and food processing applications. The partially threaded design concentrates strength where needed most while the external hex drive ensures quick installation with standard tools. With its 70,000 psi tensile strength and Rockwell B70 hardness, this fastener maintains structural integrity under sustained loads and thermal cycling, solving common failure points in aggressive environments.

Specification Summary & Compliance

This 3-1/2" length hex head screw features 1/4"-28 UNF right-hand threads with Class 2A thread fit per ASME standards, ensuring dimensional precision and interchangeability. The partially threaded configuration provides minimum 3/4" thread length with fine thread spacing for optimal performance. Manufacturing complies with ASME B18.2.1 specifications for hex head screws, and the product is fully RoHS 3 (2015/863/EU) compliant and REACH (EC 1907/2006) compliant, meeting current environmental regulations for hazardous substance restrictions.