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Deep hole drilling

high material removal rate with high accuracy

For troublefree production – try the first deep hole drill for Ejector/STS with indexable inserts and fixed insert pockets. Deep hole drilling is the machining of holes with a relatively large depth to diameter ratio. Whereas normal drilling tech-niques produce holes where the depth is rarely more than five times the diameter. In deep hole drilling the ratio may reach 150:1, and any hole deeper than ten times the diame- ter should certainly be considered a deep hole, requiring a specialised drilling technique.Deep hole drilling can employ various machine set-ups:rotating workpiece, rotating tool, or both tool and work- piece rotating. The most common, however, is for the workpiece to rotate, while the tool supplies the linear feed movement.Whichever set-up is employed, the basic principles ofdrilling still apply, and the correct choice of cutting speeds and feeds are still crucial. Satisfactory chip breaking, and removing the chips from the cutting edges without damaging tool or workpiece, is essential. Gun drilling is capable of producing smaller holes than theSingle Tube System (STS), but the STS system is far more productive (4 – 6 times) and should always be the first choice when possible. The Ejector system is an alternative to STS when drilling smaller batch quantities while it does not require a special machine.
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