Dormer Tools has introduced a new range of taps designed to obtain superior performance in material specific applications.
The new Shark Line taps feature a coloured ring that signifies the corresponding material type. The range includes spiral point taps for through-hole applications, spiral flute taps for threading blind holes and, in the case of white ring taps for cast iron, straight flute taps for both through or blind holes.
Dormer’s Marketing Manager, Simon Winstanley explains the need for material specific taps. Due to the multitude of forces exerted on the cutting edges, producing threads with taps is one of the most difficult machining processes performed by a solid round tool.
He points out that working with a general cutting geometry in materials that have low resilience will result in the actual diameter of cut thread being too large. In materials that have high resilience the threads of the tap will become enclosed by the material with increased risk of breakage. Entering the workpiece material with rake and relief angles that are specifically suited for that range of materials is essential for producing the optimum thread.
Shark Line taps are manufactured from an HSS-E-PM substrate specifically developed for taps to give the additional toughness required in addition to consistently stable properties and a superior grind-ability compared to conventional high-speed steels. These improved characteristics mean the taps have a more predictable and assured life.
Advanced geometry ensures the production of excellent threads at both high and low cutting speeds, prevents unnecessary built up edge and wear on the cutting edges to ensure longer tool life, and also provides a superior thread surface finish. The different geometries for blind and through holes have been optimised to ensure process security.
Extra fine surfaces due to improved grinding technology enable the advanced surface coating to have a smoother finish, reducing the risk of chipping, increasing tool life and allowing higher cutting speeds. Additionally, the application specific cutting edge treatment ensures optimal performance.
Yellow Shark is designed for threading low alloy steels, and is available with an electroplated Hard Chrome finish up to 5 micron thick to prevent edge build-up in materials that are prone to sticking to the cutting edges. The flute geometry has been designed to prevent swarf nesting, reducing the risk of re-cutting swarf on reversal.
Red Shark is designed for high performance thread production in alloy steels and is available in Bright finish or with TiAlN-Top coating for increased protection against abrasive wear and erosion. When combined with edge preparation it guarantees exceptional performance in alloy steels. The spiral flute version features back taper design to diminish chipping on the last few threads of the tap and reduce the torque required to reverse the tool.
Blue Shark allows the production of threads in a wide range of stainless steels. Available with Steam Temper or Super-B coatings with specific edge preparation these taps provide extended tool life in even the most difficult stainless steels.
White Shark has been developed specifically for cast iron and other short chipping materials. Available with the Steam Temper or TiAlN coating options it features a straight flute design, which enables production of both through and blind holes.
Green Shark has been developed for non-ferrous materials with a Bright or TiAlN-Top finish to provide exceptional cutting service life in aluminium and its alloys, brass and copper.