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Presently, domestic and foreign solid material deep-hole machining system in common use are classified as gun drilling system(including GSM’s QYZ deep-hole drilling system), BTA system, ejector drilling system.
http://www.gsmdrilling.com/gun-drill-shank
In deep-hole drilling, any cutter structure, cutting fluid pressure, and flow combination is for removing cutting chips from the hole in a better way. Viewed from machining principle and practice, any cutter system can drill out holes of excellent surface quality, small tolerance and good concentricity. The following is introduction of gun drilling system in common use.
Gun drilling system adopts internal cooling and external chip removal method; cutting fluid reaches the drill bit through hollow drilling stem for cooling and lubrications as well as removes cutting chips from drill bit and the V groove outside the drill stem. This system is mainly for machining small-diameter(normally smaller than 35mm) deep holes, requiring high cutting fluid pressure, which is the most common deep-hole drilling method.
