High Strength Alloy Steel Black Oxide Hex Flange Bolt
High strength alloy steel black oxide hex flange bolt is a premium fastening solution designed for heavy-duty structural connections requiring exceptional mechanical strength, stable clamping force, and reliable vibration resistance. The high strength alloy steel black oxide hex flange bolt combines a hexagonal head with an integrated flange, eliminating the need for a separate washer while distributing the clamping load evenly across the contact surface.
Manufactured from premium alloy steel and heat treated to high-strength grades, the high strength alloy steel black oxide hex flange bolt is widely used in construction machinery, automotive systems, heavy equipment, renewable energy installations, mining machinery, railway equipment, industrial machinery, and OEM manufacturing where high-load fastening performance is essential.
Product Overview
The high strength alloy steel black oxide hex flange bolt is engineered to withstand demanding mechanical loads and dynamic working conditions. The integrated flange increases the bearing surface, helping to reduce surface damage while maintaining consistent preload under vibration.
The black oxide finish provides an attractive industrial appearance while offering light corrosion protection and reducing light reflection. This high strength alloy steel black oxide hex flange bolt is ideal for applications where high torque transmission, structural integrity, and long-term reliability are required.
As a premium industrial fastener, it is commonly used by OEM manufacturers, EPC contractors, heavy equipment builders, and industrial maintenance professionals.
Product Specifications
| Item | Description |
|---|---|
| Standard | DIN / ISO / ASME / Customer Drawing |
| Product Name | High Strength Alloy Steel Black Oxide Hex Flange Bolt |
| Material | Alloy Steel |
| Thread Type | Metric Coarse Thread / Fine Thread |
| Head Type | Hex Flange Head |
| Drive Type | External Hex |
| Diameter Range | M5–M36 |
| Length Range | 10mm–300mm |
| Surface Finish | Black Oxide |
| Strength Grade | 8.8 / 10.9 / 12.9 |
| Thread Direction | Right Hand |
| Packaging | Carton, Pallet, OEM Packaging |
| Customization | Size, thread, flange diameter, strength grade, marking, packaging |
Technical Parameters
| Parameter | Value |
|---|---|
| Tensile Strength | Grade 8.8: ≥800 MPa / Grade 10.9: ≥1,040 MPa / Grade 12.9: ≥1,220 MPa |
| Yield Strength | Grade 8.8: ≥640 MPa / Grade 10.9: ≥940 MPa / Grade 12.9: ≥1,100 MPa |
| Hardness | HRC 22–39 (depending on strength grade) |
| Density | 7.85 g/cm³ |
| Corrosion Resistance | Moderate (improved by black oxide treatment) |
| Operating Temperature | -40°C to 300°C |
| Thread Tolerance | 6g |
| Manufacturing Standard | DIN / ISO / ASME / Customer Specifications |
Materials and Manufacturing Process
The high strength alloy steel black oxide hex flange bolt is manufactured using advanced forging, heat treatment, and precision machining technologies to ensure superior mechanical performance and dimensional accuracy.
- Premium alloy steel raw material selection
- Cold forging for standard bolt production
- Hot forging for large-diameter flange bolts when applicable
- CNC machining for customized specifications
- Precision thread rolling to improve fatigue resistance
- Quenching and tempering to achieve Grade 8.8, 10.9, or 12.9 mechanical properties
- Black oxide surface treatment for improved appearance and light corrosion protection
- Cleaning and anti-rust oil treatment
- Comprehensive dimensional, hardness, thread, and flange inspections
- Export-grade packaging for safe international transportation
Each high strength alloy steel black oxide hex flange bolt is manufactured under strict ISO quality management standards to ensure stable quality and reliable industrial performance.
Applications of the Product
High strength alloy steel black oxide hex flange bolts are widely used in:
- Construction machinery
- Heavy industrial equipment
- Automotive manufacturing
- Renewable energy systems
- Petrochemical facilities
- Mining equipment
- Railway engineering
- Industrial machinery
- Manufacturing systems
- Steel structures
The integrated flange design improves load distribution while the high-strength alloy steel construction provides outstanding performance under heavy loads and vibration.
Why Choose This Product
- Premium alloy steel raw material
- High-strength grades 8.8, 10.9, and 12.9 available
- Integrated flange eliminates separate washers
- Excellent load distribution
- Stable mechanical performance
- High fatigue resistance
- Black oxide finish for industrial appearance
- Long service life
- Bulk supply capability
- OEM and ODM customization support
- Fast delivery and global export experience
The high strength alloy steel black oxide hex flange bolt delivers dependable fastening performance for demanding industrial applications.
Why Choose Flybear
Flybear is a professional manufacturer specializing in industrial fasteners and customized fastening solutions for global customers.
Our strengths include:
- Advanced cold forging, hot forging, and CNC machining facilities
- Complete in-house heat treatment and surface finishing capabilities
- Large inventory and flexible production capacity
- OEM and ODM manufacturing according to drawings
- Professional engineering and technical support
- Strict ISO quality management system
- Extensive global export experience
- Fast delivery and responsive technical consultation
Flybear supplies reliable fastening products for OEM manufacturers, distributors, EPC contractors, and industrial buyers worldwide.
Quality Inspection and Control
Every production batch undergoes comprehensive quality inspection, including:
- Chemical composition analysis
- Tensile strength testing
- Yield strength verification
- Hardness testing
- Salt spray testing (upon request)
- Thread gauge inspection
- Dimensional inspection
- Surface finish inspection
- Flange geometry inspection
- Packaging inspection
All manufacturing processes comply with ISO quality management standards to ensure consistent quality and dependable performance.
Selection Guide
When selecting a high strength alloy steel black oxide hex flange bolt, consider:
- Strength grade (8.8, 10.9, or 12.9)
- Bolt diameter and length
- Required preload and clamping force
- Working load requirements
- Indoor or outdoor operating environment
- Corrosion protection requirements
- Matching nuts and flange surfaces
- Applicable engineering standards
Selecting the proper specification improves fastening reliability, equipment safety, and service life.
FAQ
1. What is a hex flange bolt?
A hex flange bolt features an integrated flange beneath the head that distributes load and often eliminates the need for a separate washer.
2. What are the available strength grades?
Common grades include 8.8, 10.9, and 12.9 for various industrial load requirements.
3. What is the purpose of the black oxide finish?
Black oxide improves appearance, reduces glare, and provides light corrosion protection when combined with protective oil.
4. Can custom sizes be manufactured?
Yes. Flybear offers OEM and ODM production for custom dimensions, thread types, flange sizes, head markings, and packaging.
5. How can I request a quotation?
Please provide the required size, strength grade, quantity, surface finish requirements, drawings (if available), and application details.
The high strength alloy steel black oxide hex flange bolt combines exceptional mechanical strength, precision manufacturing, and reliable fastening performance, making it an ideal solution for heavy-duty industrial and engineering applications.
We always adhere to the philosophy of quality first and customer first, providing customers with high-quality fastener products and one-stop fastener solutions.
For quotations, customization, and technical support, please Contact Us.
