Socket Head Cap Screws
Standards: Alloy Steel & Stainless Steel Low Heads
Hex Head Cap Bolt: - 12.9 Hex Head Cap Bolt: - 12.9 Button Head Socket Screws

Threaded Rods Square Head Cap Screws Pressure Plugs: Dry Seal Plugs
Coated Level-Seal®
Hex Nuts

Shoulder Screws Dowel Pins Metric Socket Screw Products Flat Head Socket Screws

Reliability, higher pressures, stresses and speeds in today's machines and equipment demand stronger, more reliable joints and stronger, more reliable fasteners to hold them together. Unbrako® high quality, high strength socket cap screws offer joint reliability and safety with maximum strength and fatigue resistance ensuring you a superior, safer product that meets your most challenging fastener and joint issues.

Unbrako offers the following socket screw and related products:

  • Socket Head Cap Screws

    • Standards -- Alloy Steel & Stainless Steel

    • Low Heads

  • Pressure Plugs

    • Dryseal



  • Shoulder Screws

  • Flat Head Socket Screws

  • Button Head Socket Screws

  • Socket Set Screws

  • Square Head Set Screws

  • Hex Keys -- Short Arm, Long Arm and 6" Long Arm

  • LOC-WEL® Self-Locking Socket Screws

  • Dowel Pins

  • Metric Socket Screw Products

Unbrako manufactures a range of high tensile, engineered industrial fasteners. These precision products are designed primarily for critical vehicle applications, including engine bolts and studs, brake push rods and body bolts. Engineered fasteners are often expected to withstand high-fatigue loads or cycles over a prolonged period of time.

To produce fasteners with special performance qualities, Unbrako products introduce special fatigue strengthening features.

Unbrako prides itself for it's sustained performance over time to meet specification or relevant standard and to consistently deliver to schedule. To maintain this edge, Unbrako utilizes special bolt making equipment, including the latest in cold heading and thread rolling technology, and a state of the art heat treatment plant comprising integrated continuous processing.

Each product passes through a series of processes before it is finished and dispatched to the consumer. Most products pass through the following processes:

  • Cold heading

  • Secondary operations-repetitive machining and thread rolling

  • Heat treatment

  • Surface finishing/coating

  • Adhesive/sealant patch application

  • Testing

Certified materials are procured from approved suppliers. The raw materials for most products are alloy steel or medium carbon steel, supplied in wire form. Each piece of metal is compressed in a series of dies until it takes on the shape of the required bolt. The bolt may then be pointed on one end and thread rolled by the same machine.

These processes include the turning, drilling, grinding, and tapping of fasteners. Thread rolling may also be done as a secondary operation, prior to, or after heat treatment.


  1. Hardening
    The parts are heated to a high temperature (870-880 degrees C) then quenched in oil.

  2. Tempering
    The tempering process involves re-heating the parts to a temperature that softens back the extreme hardness of the part - so that it still remains strong, but becomes less brittle.

These processes may be carried out by approved outside contractors, as in the application of coatings and finishes. Specialist contractors used by Unbrako are quality approved, long term partners of Unbrako, providing a variety of coatings such as Dacromet, Corshield, Phospate, Zinc or other as required.

Commonly used are a range of Loctite or other thread applicators that provide for thread sealing or prevent self-unlocking of fasteners in vibration related applications.

Our methods of manufacture and control are standardized for consistency in product quality and service. All the quality and production systems are designed to meet the requirements of QS-9000 and ISO 9002. There are various aspects of our products that must be measured to ensure quality, including dimensional, mechanical and visual properties.

Hardness, tensile strength, offset-yield characteristic and micrographic material structure testing and examination are routinely performed. This testing is carried out on sample products in Unbrako's own Quality Assurance Laboratory, accredited to NATA requirements.

  • Strength

  • Dimensions

  • Structure