High performance thread forming

High performance thread forming

A major breakthrough for the internal threading of blind and through holes that enables higher processing speeds, gives extended tool life and stronger and higher quality thread forms has is claimed by LMT Fette with the development of its HPF forming taps. The new threading system comprises an interchangeable solid carbide insert with through the holder coolant feed direct to the cutting zone. In addition to higher productivity gains, the replacement cost of the carbide threaded insert should also be less than a one-piece solid carbide tap.

Now available from tooling specialist LMT Fette of Coventry, UK, the HPF design incorporates a special toolholder, that is able to accept a solid carbide insert with a choice of metric, UNC, UNF and BSP forms that is secured by a central locking screw.

Thread depths can reportedly be produced to a ratio up to three times the diameter and because the form is rolled, thus creating a compacted grain flow rather than cutting across the grain of the material. The resulting thread is said to be stronger and has a hardened, burnished surface to high orders of precision and consistency.

As a result this new tool claims excellent levels of security in the machining process. Tool life is also said to be extended by the use of a coated solid carbide insert enabling flank wear to be reduced, chipping of the flute is eliminated and breakage unlikely, even when the tool is driven by a high-torque spindle in difficult materials.

Applications in materials with an elongation co-efficient of more than 8 per cent and tensile strength up to 1,000N/mm² are ideal and Fette TiCN Plus PVD multi-layer coated thread inserts are available in M8£1.25 to M18£2.5 p, 5/16 to 3/4 UNC and UNF and between G 1/8 to G 1/2 in. BSP thread forms.

A range of heavy duty, solid carbide drills are also available from LMT Fette to suit the thread sizes as well as Bilz SCN Synchro slim chucks that provide up to 4mm of length adjustment and options of internal coolant supply. Bilz is an LMT company.

Details available from: LMT Fette Limited; Tel: +44 (0) 24 7636 9770; Fax:+44 (0) 24 7636 9771; web site: www.LMT-tools.com