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die in combination with a knurl


die in combination with a knurl

Efficiency through innovation


Cost savings by using a die in combination with a knurl

The internal threads of a fitting are usually parallel threads, whereas the external threads are mainly conical. As a rule, this combination is self-sealing (metallic sealing threads). KoordinatenmessdorneFor various reasons, however, sealing tape or hemp is also used.

Sealing is usually achieved by means of a PTFE (polytetrafluoroethylene) Teflon© tape, which is wound over the external thread before assembly. The tape should lie as closely as possible on the thread so that it does not come loose when screwed in.

In order to ensure a better hold of the sealing tape or hemp, a knurled structure is applied to the outer diameter of the tapered external thread in many applications. On the one hand, this knurled structure is intended to simplify the winding of the sealing material and prevent it from coming off during assembly.

Koordinatenmessdorne mit 3D TasterSo far the thread and the knurl have been manufactured in 2 operations. In cooperation with one of our customers we have developed a tool which combines both operations in one tool.
By using a die holder, a modified die and an integrated knurling tool, we were able to achieve a considerable reduction in cycle time. So far, the sizes R1/2 and R3/4 have been successfully tested.
When selecting the machine-side interface (VDI, HSK, SK or others), we act on customer request.
With our more than 100 years of experience as the world's leading manufacturer of precision thread cutting dies, we support the design, procurement and use of such a solution.

A video about this tool system can be found on our YouTube channel under the following link:



We would be pleased to present this tool system to you in detail personally or via web meeting. Feel free to contact our application engineers on +49 7432 9087 754.

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