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Gun drill is a kind of precision Cnc deep hole making tool which can be used to drill very deep holes in various workpiece materials. The Cnc deep hole making tool has a unique head shape that is different from the traditional twist drill and a chip flute that runs through the entire length of the tool. When the gun drill is used for machining, the coolant is introduced into the cutting area through the channel inside the tool, and the chips are taken out of the hole through the chip flute. In addition, the drill sleeve (also called "guide sleeve") on the cutter head has a squeezing effect on the hole wall during drilling, so holes with extremely high diameter and roundness accuracy can be obtained. This "internal cooling, external chip removal" structural feature makes gun drills completely different from other deep hole drilling tools. The advantages of gun drills are also reflected in this.
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