Hex Bolt (Full Thread) Diameter Range: 1/4" to 2" (M6 to M48) SS304 SS316 Automotive Frame & Suspension
Product Description: Hex Head Bolts (Hex Cap Screws)
Product Summary
Our Hex Head Bolts – also known as hex cap screws or hexagon head bolts – are precision fasteners designed for high torque applications in structural, industrial, and heavy equipment assemblies. Available in Grade 2, Grade 5, Grade 8, and stainless steel 304/316, these bolts feature a forged hex head that accepts standard wrenches for reliable tightening. Full thread and partial thread options allow optimized performance for clamping or shear load scenarios. With finishes ranging from zinc plated to hot dip galvanized, our hex bolts provide consistent thread engagement, head marking traceability, and tensile strengths up to 150,000 psi.
Technical Specifications
| Parameter | Details |
|---|---|
| Product Name | Hex Cap Screw / Hex Bolt (Full or Partial Thread) |
| Diameter Range | 1/4" to 2" (M6 to M48) – standard; custom sizes available |
| Length Range | 1/2" to 24" (12 mm – 610 mm) |
| Thread Types | UNC (Unified Coarse) / UNF (Unified Fine) |
| Thread Tolerance | Class 2A (external thread) |
| Head Standard | ASME B18.2.1 (hex cap screw) |
| Wrench Size | 1.5 × bolt diameter (standard across grades) |
| Grades & Materials | Grade 2 (low carbon), Grade 5 (medium carbon Q&T), Grade 8 (alloy steel), Stainless 304, Stainless 316 |
| Tensile Strength (min) | Grade 2: 74,000 psi / Grade 5: 120,000 psi / Grade 8: 150,000 psi / 304: 70,000 psi / 316: 70,000 psi |
| Proof Load (min) | Grade 5: 85,000 psi / Grade 8: 120,000 psi |
| Yield Strength (min) | Grade 5: 92,000 psi / Grade 8: 130,000 psi |
| Hardness (Rockwell) | Grade 5: C25–34 / Grade 8: C33–39 |
| Thread Configuration | Full thread (threads to head) or Partial thread (plain shank) |
| Finishes / Colors | Zinc plated (clear/blue/yellow), Hot dip galvanized (dull gray), Black oxide (dark), Phosphated & oiled (black-gray), Passivated stainless (silver) |
| Head Markings | Grade 5: 3 radial lines; Grade 8: 6 radial lines; Stainless: often "S" or "304/316" |
| Corrosion Resistance (salt spray) | Zinc: 96 hr; HDG: 1000+ hr; 316 stainless: passivated > 2000 hr |
| Standards | ASTM A307 (Grade 2), ASTM A449 (Grade 5), ASTM A354 (Grade 8), ASTM F593 (stainless) |
Product Applications
Structural Steel Construction relies on hex head bolts for beam-to-column and beam-to-beam connections.
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Steel building frame assembly – columns, rafters, and purlins
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Bridge girder and truss connections (high strength structural bolts)
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Highway sign and light pole base plates
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Pre-engineered metal building erection
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Transmission tower bolted joints
Heavy Equipment and Machinery demand high torque capability and shear strength.
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Bulldozer, excavator, and crane assembly
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Mining equipment – crushers, conveyors, and screens
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Agricultural implements – plows, planters, and harvesters
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Industrial press and stamping machine frames
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Wind turbine tower and nacelle bolts
Automotive and Transportation use Grade 8 and stainless hex bolts for critical safety components.
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Truck frame and suspension mounting
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Engine block and transmission housing assembly
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Trailer hitch and towing hardware
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Railcar coupler and brake system fasteners
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Heavy-duty axle and wheel hub connections
Flanged Joints and Pressure Vessels require heavy hex bolts with controlled torque.
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Pipe flange bolting (ANSI/ASME B16.5)
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Pressure vessel manway and head closures
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Heat exchanger channel cover bolts
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Pump and valve body mounting
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Boiler access door fasteners
Infrastructure and Utilities benefit from corrosion-resistant finishes.
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Water treatment plant piping supports
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Bridge expansion joint hardware
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Marine dock and pier structural connections
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Solar panel array mounting frames
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HVAC equipment base mounting
Product Advantages
Choose Hex Head Bolts for reliable torque transfer, strength traceability, and application-matched configurations.
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High Torque Capacity: Hex head design accepts standard wrenches, sockets, or impact tools without cam-out.
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Grade Markings: Radial lines on head (3 for Grade 5, 6 for Grade 8) allow visual strength verification.
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Full or Partial Thread: Full thread for maximum thread engagement; partial thread with plain shank for shear applications.
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Material Options: Low carbon (Grade 2), medium carbon heat treated (Grade 5), alloy steel (Grade 8), or stainless (304/316).
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Corrosion Resistance: Zinc plating for indoor; hot dip galvanized or stainless 316 for outdoor/marine.
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Dimensional Precision: Class 2A thread tolerance ensures smooth assembly with standard nuts and tapped holes.
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Wide Size Range: From 1/4" to 2" diameter, lengths up to 24" – one source for most bolting needs.
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Traceable Compliance: Manufactured to ASTM standards with mill test reports available.
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Cost Effective: High volume production keeps pricing competitive without sacrificing quality.
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Interchangeable: Standard head dimensions per ASME B18.2.1 fit all common hand and power tools.
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FAQ
1. Are you trading company or manufacturer ?
We are manufacturer ,You can see the certification.
2. How long is your delivery time?
Generally it is 5-10 days if the goods are in stock. or it is 15-20 days if the goods are not in stock, it is according to quantity.
3. Do you provide samples ? is it free or extra ?
Yes, we could offer the sample for free charge but need pay the cost of freight.
4. What is your terms of payment ?
Payment<=1000USD, 100% in advance. Payment>=1000USD, 50% T/T in advance ,balance before shippment.
Get in Touch
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