HELICOIL® thread inserts – approved and high-strength

For over 60 years, HELICOIL® thread inserts have been creating high-strength threads in your low-strength materials.

The stainless steel coil thread inserts are formed into elastic spirals in proven quality from wire with rhombic profile. They feature high wear resistance and low thread friction within small tolerances. HELICOIL® coil thread inserts by Böllhoff also stand for high surface finish and heat resistance.


HELICOIL® tangfree – a major step forward in HELICOIL® technology

Innovative installation

Tangfree thread insert

Low tool wear

Improved quality

The system in the focus

Your benefit: You obtain a complete system solution consisting of coil thread inserts and specially developed installation tools. This reduces your costs and assures the quality of the joints. An overview of the installation tools is provided on pages 11 to 13.

Competence for your thread

Feel free to contact us for customised HELICOIL® tangfree thread inserts. It is our expertise. Please do not hesitate to ask.


The innovative production concept

The innovative coil of the insert allows installation from both ends with identical quality. Thanks to the reduced thread on both ends and to the inlet-optimised coil ends, the HELICOIL® tangfree thread insert can be installed without special alignment. The coil thread insert does not have a preferable end for installation. Therefore, the HELICOIL® tangfree does not need to be orientated for successful installation.

This ensures quick and safe installation. The HELICOIL® tangfree can be easily screwed onto the mandrel and smoothly enters the prepared tapped hole. During loading, the spring-mounted installation blade grips into the notch of the coil thread insert and securely installs it in the prepared tapped hole.

As a result of the optimised geometry of the HELICOIL® tangfree thread insert, tool wear is minimised. Tool blade life for HELICOIL® tangfree is longer and maintenance of the installation tools is easier than for the HELICOIL® tangless tool generation. Particularly the replacement of the tool blade has been optimised.

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Product types

HELICOIL® tangfree thread inserts are available in two versions: HELICOIL® tangfree free running and HELICOIL® tangfree screwlock.

Both versions can be screwed in like a screw with an installation mandrel.

HELICOIL® tangfree free running

Every thread of the thread insert has a precision-formed profile and is free running. The result is an internal thread true to gauge that can be installed from either end.


HELICOIL® tangfree screwlock

HELICOIL® tangfree screwlock has the same advantages relating to thread technology as HELICOIL® tangfree free running. In addition, an integrated screw-locking area serves as a screw lock. Locking of the screw is achieved by one or several polygonal-shaped threads that clamp the flanks of the screwed-in screw. The result is an elastically resilient frictional locking.



Fields of application for HELICOIL® tangfree thread inserts:

Automotive industry

General industry

Aerospace industry



HeliCoil tangfree