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Unbrako High-tensile Fasteners

Established in 1911, Unbrako is the ultimate authority in high tensile industrial fasteners and remains the socket screw by which all others are measured .

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NABL Certified Lab

The NABL ISO/IEC 17025 certified lab facilitates in maintaining consistent high quality. Strict quality checks are done at every stage to meet the needs of most demanding industries.

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Specialized Coatings

A variety of coatings are done in-house: Hot Dip Galvanizing, Mechanical Galvanizing, Zinc / Zinc- Nickel Electroplating, PTFE, Geomet® , Delta Dorken® and Unbrako Wiscoat, among others.

Advantages built into every detail


Higher Tensile Strength

Unbrako tensile specifications are 10,000 psi higher than industry standard - while maintaining the core hardness range.


E-CODE Head Marking

The ultimate in fastener traceability - from its original manufacturing lot, raw material chemistry to performance test results.


Compound Fillet Radius

This design change alone is responsible for doubling fatigue life at critical head-shank juncture.


Radiused Root Runout (3R)

Provides a smooth form that distributes stress and increases fatigue life of thread run-out as much as 300% in certain sizes.


Wide Root Thread Form

An Unbrako development that doubles the fatigue life compared to flat root thread forms.


Etching for Thread Laps

The only method to detect thread laps is that random samples of rolled threads are etched in heated acid, and then examined under a stereo microscope.


Forged Heads

The flow lines of the material are continuous, resulting in increased strength, better installation ability, and a longer product life.


Rolled Threads

Roll threading compresses the material’s grain flow and enhances fatigue resistance.

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