Iscar says its deep-hole drilling system is a viable alternative to traditional gundrilling. The modular system of brazed and indexable threaded drilling heads feature single- or double-tube shank types to expand the application range of traditional gundrills. The single-tube (STS) drill's coolant system introduces fluid through the gap between the drill and the hole, driving the chips through the tube. Conversely, with the double-tube (DTS) drill, the coolant is introduced between the tubes and drives the chips through the inner tube.
According to the company, the drills are suited for applications where the drilling depth-to-diameter ratio is more than 10. They are available in diameters ranging from 0.315" to 10", and the maximum possible depth ratio is 300 times the diameter.