HSFG Bolts Manufacturer in India – High Strength Friction Grip Structural Bolts
| Product Details |
Metric |
Inches |
| Dia |
M12 to M36 |
1/2″ to 3″ |
| Length |
40 MM - 500 MM |
upto 20 |
| Grade |
8.8, 10.9 |
|
| Standard |
EN 14399, IS 3757, ASTM A325 |
|
Weight Chart
Standard & Other names: IS 3757 High Strength Friction Grip (HSFG) Bolts, EN 14399 Structural Bolt Assemblies, ASTM A325 Structural Bolts, Heavy Hex Structural Bolts, High Strength Structural Fasteners, Structural Bolt & Nut Assemblies, Bridge Fasteners, RDSO Approved Structural Fasteners, Zinc Flake Coated Structural Bolts
New Star Industries is one of India's leading HSFG Bolt manufacturers, producing high-strength friction grip structural bolts for steel structures, bridges, transmission towers, industrial plants, metro projects, and PEB buildings. Our HSFG bolt assemblies are manufactured in accordance with IS 3757, EN 14399, ASTM A325, and other international standards, ensuring exceptional strength, reliability, and long service life.
Manufactured in modern facilities with strict quality control, our structural fasteners are trusted by infrastructure contractors, EPC companies, OEMs, and fabrication industries across India and international markets.
Why Choose New Star Industries HSFG Bolts?
Our HSFG bolts provide a stable joint and a solid hold with no weak points in the connection. The large clamping force applied to the connected elements is due to the significant tensile stresses developed in the bolts during installation. The frictional resistance in the HSFG bolts is capable outside the hole, which drastically reduces the possibility of failure at the net section.
- Vibration Resistance: The nuts are prevented from loosening because the bolts are tensioned up to proof load.
- Safety: Fire hazards can be avoided due to their inherent strength and material integrity.
- Cost-Effective: Fewer bolts are required to attain the desired structural strength compared to ordinary bolts, reducing both material costs and manpower requirements.
- Low Noise: As they are tightened with calibrated wrenches rather than pneumatic hammers, the installation noise is significantly lower.
Frequently Asked Questions
What is the difference between HSFG bolts and ordinary high-tensile bolts?
Ordinary bolts transfer loads through bearing and shear on the bolt shank. In contrast, HSFG (High Strength Friction Grip) bolts are tightened to a specific tension to create a massive clamping force, transferring the load through friction between the connected surfaces, eliminating joint slip.
Why do HSFG bolts have an "S" suffix (e.g., 8.8S or 10.9S)?
The "S" stands for Structural. HSFG bolts have a larger head size (Across Flats) compared to standard bolts to distribute the heavy clamping force over a larger area, protecting the structural plates from deformation.
What standards govern HSFG bolt manufacturing in India?
New Star Industries manufactures HSFG bolts in compliance with IS 3757, IS 4000, and IS 6623/6649 for nuts and washers. We also provide products meeting international EN 14399 and ASTM A325 standards, including RDSO-approved variants for railways.
Is it necessary to use a specific washer with HSFG bolts?
Yes, HSFG bolts must be used with hardened circular washers (conforming to IS 6649). These washers are essential to maintain the high preload tension and prevent the bolt or nut from digging into the structural steel.
Why are HSFG bolts preferred for bridge and girder construction?
Bridges and girders face constant vibration and dynamic loads. HSFG bolts provide superior fatigue resistance because the friction-grip mechanism prevents any relative movement between the joined plates, ensuring long-term structural safety.
