Ballnose/toroidal milling inserts are more efficient

A new generation of ballnose and toroidal indexable milling inserts with integrated cooling flutes for through-the-tool air supply to provide more efficient chip evacuation will accommodate both rough and semi-finish cycles. The new inserts also have the added advantage of an optimised centre geometry that will improve the normally troublesome rest metal cutting area where the tool tends to rub rather than cut at the mid-point of the insert. The development of the Air-Jet insert range, specifically for dry cutting applications, by LMT’s Kieninger mould and die division drew together the expertise of the Group’s Fette operation in advanced compacting technology, Boehlerit in high precision sintering and Bilz for its tool holding. As a result, the new inserts are also able to maximise chip removal through a smoother cutting action generated by the helical cutting edge and a positive chip former that together create lower cutting forces. And by improving levels of precision during roughing cycles, finishing cuts are brought closer to the final contour requirement. As a result, the finishing process can be fully optimised and therefore machine utilisation and productivity improved giving greater confidence for running in unmanned or automatic cycles. The ballnose spherical insert is available in 12 mm, 16 mm, 20 mm, 25 mm and 32 mm diameters and the toroidal insert in 10 mm, 12 mm, 16 mm and 20 mm diameters. Both Air-Jet insert types are available in LC 630Q and LC 610Z grades. The LC 630Q (HC-K30) is a PVD-AICrN high wear resistant coated grade for alloyed and non-alloyed high tensile tool steels up to 54 HRC. This grade is ideal for medium cutting speed applications under dry machining conditions. Meanwhile, LC 610Z (HC-K10) is a PVD-TiAIN coated insert produced from a super micrograin carbide substrate that is ideal for high tensile materials, grey, modular and malleable cast irons and also hard machining applications. These inserts were recently used on a machining trial on 312 tool steel, with a 16 mm diameter cutter set to 6 mm depth of cut at 180 m/min with 0.6 mm feed per tooth. Material was removed at over 100 cm3/min.