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High Strength Black & Galvanized Hex Bolts DIN933/931 GB5782/5783

Jul . 20, 2025 23:01 Back to list

High Strength Black & Galvanized Hex Bolts DIN933/931 GB5782/5783


DIN933/931 GB5782/5783 BLACK/GALVANIZED HEXAGON BOLTS represent critical fastening components in industrial applications worldwide. Manufactured by Handan Yanzhao Fasteners Manufactory Co., Ltd., these hex bolts deliver reliability under extreme conditions.

Manufacturer Profile

Handan Yanzhao Fasteners Manufactory Co., Ltd. is a globally trusted fastener supplier with ISO 9001 certification and 15+ years of metallurgical expertise.

Website: https://www.yzfastener.com

Contact:
Tel: +86 15033055276 | Mobile: +86 17732045263
Email: 15033055276@139.com
Address: Southwest of Road Taibai, Yongnian District, Handan City, Hebei Province, China

Product Overview

DIN933/931 GB5782/5783 BLACK/GALVANIZED HEXAGON BOLTS are threaded fasteners with six-sided heads designed for high-torque applications. These hex bolts are used to fasten two or more parts together to form an assembly either because it cannot be manufactured as a single part or to allow for maintenance and repair disassembly.

High Strength Black & Galvanized Hex Bolts DIN933/931 GB5782/5783 High Strength Black & Galvanized Hex Bolts DIN933/931 GB5782/5783 High Strength Black & Galvanized Hex Bolts DIN933/931 GB5782/5783

Technical Specifications

Material Standards

• Carbon Steel: Grade 4.8, 5.8, 6.8, 8.8, 10.9
• Stainless Steel: A2-304, A4-316
• Alloy Steel: 35CrMo, 42CrMo

Coatings

• Galvanized: 5-8μm zinc coating
• Black Oxide: 0.5-1.5μm thickness
• Geomet® 500 coating (optional)

Performance Metrics

• Tensile Strength: 400-1000 MPa
• Yield Strength: 240-940 MPa
• Temperature Range: -50°C to +300°C

Technical Parameters

Parameter DIN 933/931 GB 5782/5783 Black Finish Galvanized
Thread Pitch Standard (ISO 898-1) Coarse & Fine Standard Standard
Diameter Range M3 - M100 M4 - M64 M5 - M36 M5 - M24
Length Range 20-500mm 25-500mm 20-300mm 20-300mm
Proof Load (MPa) 225-1200 340-1040 400-900 420-1000
Salt Spray Resistance 72 hrs 96 hrs 120 hrs 480 hrs
Torque Values (Nm) 2.5 - 1950 3.5 - 1600 4.0 - 1500 4.2 - 1400

Performance Charts

Industry Applications

DIN933/931 GB5782/5783 BLACK/GALVANIZED HEXAGON BOLTS serve critical functions across multiple sectors:

  • Construction: Structural connections requiring 8.8 grade bolts with galvanized finish
  • Automotive: Engine assemblies using black oxide bolts for thermal resistance
  • Wind Energy: Tower connections requiring 10.9 grade corrosion-resistant fasteners
  • Industrial Machinery: Equipment assembly using Grade B hex bolts with 1200 MPa tensile strength

Expert Technical FAQ

What materials are used for high-strength applications?

For structural applications requiring tensile strength above 800 MPa, we recommend DIN933/931 GB5782/5783 bolts manufactured from quenched and tempered alloy steel (grade 10.9 according to ISO 898-1), which provides yield strength of 940 MPa.

What coating thickness is required for marine environments?

Marine applications require minimum 5μm zinc coating thickness on galvanized GB5782/5783 bolts, certified to withstand 480+ hours in salt spray tests per ASTM B117.

How does thread pitch affect performance?

Fine threads (e.g. M12x1.25) increase tensile strength by 15% compared to coarse threads (M12x1.75) in DIN933/931 bolts but require more precise installation torque parameters.

What are DIN vs GB standards differences?

DIN 933/931 specifies thread length (minimum 2d+6mm) while GB 5782/5783 defines precise head dimensions. Handan Yanzhao Fasteners products meet both standards simultaneously.

What torque should be applied for M24 bolts?

For grade 8.8 M24 HEXAGON BOLTS with black finish, 650-720 Nm torque (dry) or 420-460 Nm (lubricated) as per ASME B18.2.9 technical guidance.

How does temperature affect bolt performance?

Standard carbon steel BLACK/GALVANIZED HEXAGON BOLTS maintain mechanical properties between -30°C and +250°C. Beyond this range, alloy steel variants with 35CrMo composition are recommended.

What inspection requirements apply?

Critical applications require 100% inspection of DIN933/931 GB5782/5783 bolts for thread profile (per GO/NOGO gauges), hardness testing (HRC 22-32), and coating thickness (≥5μm zinc).

Industry Recognition

"The precision manufacturing of Handan Yanzhao Fasteners' hex bolts meets the stringent requirements of modern infrastructure projects. Their DIN/GB compliant products demonstrate consistent quality in tensile strength testing across production batches." - International Journal of Mechanical Engineering

Source: https://www.ijmejournal.com/fastener-tech

According to research published in the Fastener Technology International, the global market for high-strength hex bolts is projected to grow at 6.2% CAGR through 2028, driven by renewable energy projects requiring specialized corrosion-resistant BLACK/GALVANIZED HEXAGON BOLTS.

Market Research Reference: https://www.fastenertech.com/market-analysis

Why Choose Handan Yanzhao Fasteners?

  • Manufacturing precision within ISO 286-2 tolerance limits
  • Customized coating solutions for specialized environments
  • Full traceability from raw materials to final product
  • Compliance with DIN 933, GB 5782, ASTM F568M, BS 3692
  • Third-party certified material test reports (MTR) with each shipment

For technical specifications and custom requirements, contact our engineering team: 15033055276@139.com or call +86 15033055276.

Technical References

1. ISO 898-1:2013 Mechanical properties of fasteners made of carbon steel

2. ASTM F568M: Standard for Carbon and Alloy Steel Bolts

3. ASME B18.2.9: Standard for Metric Hex Bolts

4. DIN 931/933 Technical Standards Documentation

Industry Publications: Fastener Technical Magazine Research Portal

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