1/4-28 Hex Bolt: High-Strength Fastening Solution for Demanding Applications

In the world of precision assembly and heavy-duty machinery, the reliability of every component is paramount. The 1 4 28 hex bolt stands as a critical fastener in this ecosystem, engineered to deliver exceptional clamping force and vibration resistance. This product page details our premium-grade hex bolts, designed to meet the rigorous standards of industrial manufacturing, automotive repair, and aerospace applications. We provide a consistent, high-quality supply chain solution for businesses that cannot afford fastener failure.

Product Overview

Our 1/4-28 hex bolt is a standardized, coarse-threaded fastener characterized by a hexagonal head and a unified national coarse (UNC) thread pattern. The "1/4" denotes a nominal diameter of 0.25 inches, while "28" specifies 28 threads per inch, offering a robust balance between tensile strength and assembly speed. Manufactured from high-grade materials and subjected to stringent quality control, these bolts are the go-to choice for creating secure, durable, and repairable joints in metal-to-metal applications across global industries.

Key Features

• Premium Material Integrity: Fabricated from Grade 5 medium carbon steel or A2/A4 stainless steel, ensuring optimal strength, durability, and corrosion resistance tailored to your environmental needs.
• Precision Threading: Rolled threads for superior fatigue strength and consistent engagement, reducing the risk of cross-threading and ensuring a secure fit every time.
• Full Traceability: Each batch is fully traceable to its material origin and heat lot, providing quality assurance documentation for critical applications.
• Versatile Finishing: Available in plain, zinc-plated, hot-dip galvanized, or dichromate finishes to combat corrosion and meet specific industry specifications.
• Rigorous Quality Assurance: 100% dimensional inspection and batch testing for hardness, tensile strength, and proof load to exceed ASTM, SAE, and ISO standards.

Technical Specifications

Application Scenarios

The versatility and strength of the 1 4 28 hex head bolt make it indispensable across multiple sectors:

• Industrial Machinery: Used in the assembly of frames, guards, motor mounts, and gearboxes where vibration resistance is critical.
• Automotive & Heavy Equipment: Essential for engine components, suspension systems, and structural repairs in OEM manufacturing and aftermarket service.
• Metal Fabrication & Construction: Ideal for structural steel connections, platform assembly, and securing heavy fixtures.
• Aerospace & Defense (Specific Grades): Employed in non-critical airframe applications and ground support equipment, adhering to strict material and traceability protocols.
• Electronics & Telecom Enclosures: Securing ruggedized casings and rack-mounted equipment that require secure, grounded fastening.

Advantages

Choosing our 1/4-28 UNC hex bolt provides tangible benefits to your production line and end products:

• Enhanced Joint Reliability: Superior material and manufacturing consistency minimize the risk of spontaneous loosening or shear failure, reducing downtime and maintenance costs.
• Streamlined Procurement: Consistent sizing and compliance with international standards simplify your inventory management and design processes.
• Cost-Effective Durability: The right finish-material combination extends service life, even in harsh environments, offering a lower total cost of ownership.
• Global Compliance: Products are manufactured to meet or exceed major international standards, ensuring acceptance in North American, European, and Asian markets.

Why Choose Us as Your Fastener Partner

We are more than just a supplier; we are a strategic partner in your supply chain. Our focus on the 1 4 28 hex bolt category exemplifies our commitment to specialized excellence.

• Deep Technical Expertise: Our team provides application-specific guidance to select the optimal grade, finish, and length for your project.
• Scalable Global Logistics: We maintain significant stock levels for immediate shipment and support Just-In-Time (JIT) delivery programs for high-volume buyers.
• Uncompromising Quality Control: Our in-house lab and certified inspection processes ensure every bolt meets its published specifications, shipment after shipment.
• Customization Capability: We offer custom packaging, private labeling, and manufacturer-specific modifications to integrate seamlessly into your operation.

Frequently Asked Questions (FAQ)

What is the difference between a 1/4-20 and a 1/4-28 hex bolt?

The primary difference is the thread pitch. A 1/4-20 bolt has 20 threads per inch (coarser), while the 1/4-28 hex bolt has 28 threads per inch (finer). The finer thread of the 1/4-28 offers slightly better tensile strength and vibration resistance in certain materials and is often specified in applications like automotive and electronics.

What wrench size is required for a 1/4-28 hex bolt?

A standard 7/16" wrench or socket is used for the hex head of a 1/4-28 hex head bolt. Always ensure tools are in good condition to prevent rounding the corners of the hex.

Can you provide these bolts in stainless steel?

Absolutely. We commonly supply 1/4-28 hex bolts in A2 (304) and A4 (316) stainless steel for superior corrosion resistance in marine, chemical, and food processing environments. Please inquire for specific grade availability and mechanical properties.

Do you offer certification with the bolts?

Yes. We provide Mill Test Certificates (MTCs) or Certificates of Conformance (CoC) with all shipments, detailing material composition, mechanical test results, and compliance standards. This is crucial for quality audits and regulated industries.

What are the minimum order quantities (MOQ)?

We cater to both large-scale OEMs and smaller distributors. Standard items often have low MOQs (e.g., by the box). For custom specifications, we will work with you to establish a viable commercial quantity. Contact our sales team for a precise quote.

Ready to secure your supply of high-performance fasteners? Contact our technical sales team today for a competitive quote, sample request, or to discuss your specific application requirements for the 1 4 28 hex bolt.