LMT Installs Turn-Mill Centre In German Factory

LMT has installed five-axis simultaneous-machining centres and a turn-mill centre worth over GBP3.5m at LMT Fette's Schwarzebek manufacturing facility in Germany. LMT's Nanosphere coating acts as a heat shield but reacts elastically to protect the cutting tool from high thermal and mechanical stress. As a result, LMT Fette gear hobbing cutters can be run without coolant and should achieve a realistic increase in production life of at least a third over normal coated hobs.

The Twist-Free combination hobbing and deburring system enables the functions of a roughing hob, the in-cycle deburring of top and bottom flanks of each tooth and the finishing of the gear to be achieved in a single high-productivity cycle.

The single-arbour tool assembly can be applied to the hobbing of spur and helical gears and eliminates tooth-flank 'twisting' or convexity error that normally requires correction through separate finishing operations such as shaving, or grinding or honing in the hardened condition.

Korloy CBN Inserts Hard-Turn Without Cutting Fluid

Cutwel has released Korloy CBN inserts, which can be used for hard turning with no cutting fluid. Existing or standard ISO toolholders can be used to hold the inserts. Typical materials that are hard-turned are grey cast iron (180-230HB), high-temperature alloys (over 45HRC), sintered alloy, carbide roll and high-speed steel roll.

Grade KB320 is suitable for intermittent and continuous cutting on hardened steel, and Grade KB330 for heavy intermittent cutting on hardened steel. Other grades include Grade KB360 for continuous cutting on cast iron, sintered alloy, heat-resistant alloy and carbide roll, and KB420, for continuous cutting on hardened steel.

Advantages include the following: cycle times and set-ups are generally much shorter on lathes than on grinding machines; CNC lathes are generally recommended for hard turning, but manual lathes can be effective as well; hard turning requires a rigid machine with a rigid toolholder system.

CBN inserts promote faster cycle times, cut cost of machine tool investment, improve accuracy, give high-quality surface finishes, permit higher metal removal rates (two to four times faster than grinding), allow multiple operations in a single chucking, and make wet or dry cutting an option (dry cutting avoids coolant expense and disposal issues). Full technical back-up is offered on insert selection, speeds feeds and recommended depths of cut.