Princes Risborough-based Sumitomo Electric Hardmetal Ltd (www.sumitomotool.com) has released its SMD Multi-Drill for producing holes between 12 and 42.5mm in diameter and with depth-to-diameter ratios of up to 12:1.

The range has the advantage of a replaceable head, allowing up to five sizes of drill to be accommodated by a single body. Heads can also be selected to suit the machine type and power available, as well as the material being processed.

The SMD Multi-Drill programme covers the SMDH replaceable-head drill holder, the MTL drill head for general steels and the MEL head for soft steel, grey cast iron, exotic metals and low-rigidity set-ups.

Also available is MB for structural steel and single-layer laminates. Diameters can be specified in short series (3xD), long series (5¥D), deep-hole series (8xD) and ultra-deep-hole series (12xD), giving effective drilling depths up to 300mm.

A toughened body with a balanced design, along with the use of a tungsten-carbide substrate drill head with PVD coating, minimises the tool vibration and noise generated under cutting conditions.

Heat dissipation is achieved via through-the-tool coolant holes, while the rigid clamping system is designed to ensure that the exchangeable drilling heads (bolted to the body against fixed radial serrations) offer edge security and achieve repeatable hole size.

There are two variants of drill head with PVD coating: the MTL ACX70, which is for general-purpose drilling applications; and the MEL ACX80 for machines with lower-powered spindles.

MEL drill heads feature a light edge preparation and are coated with Sumitomo’s latest ACX80 for soft steel, where cutting speeds between 80 and 130m/min and feed rates between 0.15 and 0.4mm/rev can be maintained.

Stainless steel and super-alloys can be drilled between 50 and 90m/min with feed rates from 0.1 to 0.25mm/rev, and grey cast iron at 50 to 100m/min with feed rates from 0.2 to 0.45mm/rev.

MTL drill heads have a standard edge preparation and are coated with ACX70 for general carbon-steel applications with cutting speeds between 80 and 130m/min and feed rates from 0.15 to 0.35mm/rev.

Hardened steel (>45HRc) can be drilled between 50 and 90m/min with feed rates from 0.1 to 0.25mm/rev, while nodular cast-iron components can be processed at speeds from 70 to 110m/min and feed rates between 0.15 and 0.4mm/rev.

MB drill heads have a robust substrate, a reinforced edge treatment, a 150deg point angle and wide, highly polished J-grooved flute surfaces.