Machine-Operation

Deep hole drilling machines are not the most energy-intensive machines in a shop, but they use significant power. The main energy consumer is the coolant pump, which runs continuously during the drilling cycle. I’ve found several ways to reduce energy consumption without affecting cycle time or hole quality. I cut my own shop’s energy bill by 18% over two years by implementing the measures described below. Where the Energy Goes On a typical deep hole drilling machine, the energy breakdown looks like this: ...

A cold machine does not drill straight holes. The thermal expansion of the spindle, bed, and coolant changes the machine geometry during the first few hours of operation. I’ve learned to account for thermal effects in every job, and I’ve developed a warm-up procedure that eliminates the guesswork. Why Warm-Up Matters As a machine warms up, several changes happen simultaneously: The spindle bearings expand, changing the spindle position by 0.01-0.03mm The bed expands, changing the alignment between headstock and tailstock The coolant warms up, changing its viscosity and flow characteristics The ball screws expand, changing the positioning accuracy These changes are not small. I measured a 0.15mm drift in hole position on a large BTA machine over the first 90 minutes of operation. The first hole of the day was in a different location than the holes drilled two hours later. The operator had been chasing this by adjusting offsets — compensating for a problem that thermal stability would have solved. ...