Precision Engineered Industrial Bolts Manufacturer in India
15,000+
MT Annual Capacity
M6 – M72
Diameter Range
4.6 to 12.9
Strength Classes
1,000+ Hrs
HDG Salt Spray Life
BRK Industries engineers high-integrity Bolts fastener for heavy infrastructure, pre-engineered buildings, power transmission towers, solar structures, and highway safety barriers. Certified to European CE standards (EN 14399 & EN 15048) with in-house hot-dip galvanizing and fully calibrated test laboratories.
Types of Bolts We Manufacture
Manufactured to DIN, IS, EN, ASTM & BS standards. Full lot traceability with Mill Test Certification to EN 10204 3.1.
Engineering Standards & Technical Matrix
International Standards Equivalence & Property Classes
Standard Conversion & Equivalence Table
DIN / ISO / EN / BS / ASTM / IS| Fastener Type | DIN (German) | ISO (Global) | EN (Europe)/BS | ASTM (USA) | IS (India) |
|---|---|---|---|---|---|
| Hex Bolts (Partially Threaded) | DIN 931 | ISO 4014 | EN 24014 | ASTM A307 Gr. A / B18.2.1 | IS 1363 (Pt 1) / IS 1364 |
| Hex Bolts (Fully Threaded) | DIN 933 | ISO 4017 | EN 24017 | ASME B18.2.1 | IS 1363 (Pt 2) / IS 1364 |
| High-Strength Structural Preloaded | DIN 6914 | ISO 7412 | EN 14399-4 (HV) | ASTM F3125 / A325 | IS 3757 / IS 4000 |
| Hexagon Flange Screws | DIN 6921 | ISO 4162 | EN 1665 | ASME B18.2.18M | IS 16016 |
| Mushroom Head Carriage Bolts | DIN 603 | ISO 8677 | EN 28677 | ASME B18.5 | IS 2609 |
| Transmission Lattice Tower Bolts | DIN 7990 | ISO 4016 (Mod) | EN 14219 | ASTM A394 | IS 12427 |
| Square Foundation Holding Down | DIN 529 | - | BS 7419 | ASTM F1554 Gr 36/55 | IS 5624 |
Mechanical Properties & Tensile Strength by Property Class (ISO 898-1)
| Steel Grade | Tensile Strength (Rm) | Yield Strength (Re) | Elongation (A5) | Hardness Range | Typical Application |
|---|---|---|---|---|---|
| Class 4.6 | 400 MPa | 240 MPa | 22% | HRB 67 - 95 | General commercial, low stress assemblies |
| Class 5.6 | 500 MPa | 300 MPa | 20% | HRB 71 - 95 | Light structural and transmission poles |
| Class 8.8 | 800 MPa | 640 MPa | 12% | HRC 22 - 32 | High tensile engineering, steel buildings, solar mounts |
| Class 10.9 | 1040 MPa | 940 MPa | 9% | HRC 32 - 39 | Heavy structural preloaded bridges (DIN 6914), automotive |
| Class 12.9 | 1220 MPa | 1100 MPa | 8% | HRC 39 - 44 | Extreme tensile equipment, pressure clamping |
| ASTM A325 | 830 MPa (120 ksi) | 640 MPa (92 ksi) | 14% | HRC 25 - 34 | North American structural steel framing (Type 1 & 3) |
| ASTM A490 | 1040 MPa (150 ksi) | 900 MPa (130 ksi) | 14% | HRC 33 - 38 | Heavy high-strength friction grip steel joints |
Manufacturing Excellence & Quality Control
Integrated Fastener Production & Metallurgical Testing
Cold Heading & Multi-Station Forging
High-speed multi-station cold formers for high-volume precision bolts from M6 to M24. Ensures continuous grain flow around head-to-shank fillets for maximum fatigue resistance.
Tolerance: ISO 4759-1 Product Grade A & B
Hot Forging Presses up to 400 Tons
Hydraulic and friction screw hot forging lines for large diameter structural and foundation bolts (M24 through M72). Precise optical induction heating to avoid decarbonization.
Capacity: M24 to M72 / Up to 2,500 mm Length
Continuous Mesh Belt Heat Treatment
Atmosphere-controlled continuous quenching and tempering furnace lines. Automated oil quenching followed by controlled tempering guarantees uniform core hardness.
Hardness: 8.8 (22-32 HRC) / 10.9 (32-39 HRC)
Automated Circular Die Thread Rolling
Threads are 100% rolled after heat treatment (on high-tensile grades) to introduce compressive residual stress in thread roots, increasing dynamic cyclic fatigue life.
Thread Classes: 6g Metric / 2A Unified
Bolt Applications
Structural Steel
Construction
Infrastructure
Road & Guard Rails
Power Transmission
Solar Structures
Industrial Machinery
Heavy Engineering
Fabrication
Agricultural Equipment
In-House Testing Laboratory Equipment & Inspection Bench
Optical Emission Spectrometer
Full 24-element chemical analysis of incoming raw steel coils and wire rods to verify C, Mn, Cr, Mo, B and trace elements.
Universal Tensile Testing Bench (600 kN)
Measures ultimate tensile strength, 0.2% yield strength, elongation percentage, and full-size wedge tensile failure.
Salt Spray Corrosion Chamber (ASTM B117)
Accelerated cyclic corrosion testing up to 1,500+ hours to verify Hot Dip Galvanizing and Geomet flake coating integrity.
Torque-Tension Preload Bench (k-factor)
Calibrates tightening torque vs clamping tension for CE EN 14399 structural bolt assemblies to prevent over-torquing.
Digital Optical Profile Projector
Micrometer precision measurement of thread pitch, flank angle, root radius, and head concentricity.
Magnetic Particle Inspection (MPI)
Non-destructive testing to detect longitudinal surface seams or quenching micro-cracks on high-tensile batches.
Why Choose BRK Industries for Bolts?
Manufacturing Excellence
Advanced forging, thread rolling and heat-treatment capabilities.
International Standards
High Strength & Reliability
Corrosion Protection
Materials & Grades
- Carbon Steel
- Alloy Steel
- Stainless Steel — where applicable
- Various grades and strength classes
- Custom material specifications
Coatings & Finishes
Need Custom Bolts?
Frequently Asked Questions About Bolts
What types of bolts does BRK Industries manufacture?
BRK’s bolt range includes hex bolts, carriage bolts, flange bolts, hexagon head bolts, structural bolts and NIB/crash barrier bolts, along with application-specific industrial fasteners.
What DIN standard hex bolts are available?
The proposed BRK Hex Bolt range includes DIN 931, DIN 933, DIN 960 and DIN 961.
What is the difference between DIN 931 and DIN 933?
DIN 931 is a partially threaded hexagon bolt, while DIN 933 is a fully threaded hexagon bolt.
What are DIN 960 and DIN 961 bolts?
DIN 960 and DIN 961 are fine-thread hexagon bolt standards, covering partially and fully threaded configurations respectively.
What standards are used for structural bolts?
BRK’s structural range includes DIN 6914, DIN 7990, EN 14399, EN 15048 and ASTM structural specifications such as A325/F3125 and A490/F3125.
What are NIB bolts used for?
NIB bolts are application-specific fasteners used for crash barriers, guard rails and road infrastructure where the specified bolt design and standard are required.
Can BRK supply custom bolts?
For custom requirements, customers can submit drawings, samples or detailed specifications for technical review and quotation.