Common Types of Carbide Deep Hole Machining

When processing precision parts of deep-hole workpieces, since the tool handle is limited by the diameter and depth of the hole, it is required that the tool handle should be slender, but the slender tool handle will cause its rigidity to be poor, and it is easy to generate vibration and tool loss during turning . In addition, due to the depth of the hole, the drill bit is easily deflected during the drilling process, causing the axis of the hole to be skewed.

Due to the deep hole, the chip is not easy to remove, the cutting fluid is difficult to effectively cool to the cutting area, and the tool is cut in the deep hole, the wear of the tool and the damage of the tool body cannot be observed, making the processing quality difficult to control. 

1. Gun hole drilling and external chip removal

When processing deep holes with small diameters in precision parts, gun hole drills are generally used, and the gun hole drills are welded with high-speed steel or hard alloy cutter heads and seamless steel pipe handles. A V-shaped groove is pressed on the handle as a channel for chip discharge. The waist hole is the outlet of cutting fluid.

2. High pressure internal chip removal drill

The high-pressure internal chip removal drill uses high-pressure and large-flow cutting fluid to enter the cutting area from the oil seal head through the gap between the deep hole drill and the hole wall, and the chips are discharged from the middle of the chip removal outer casing under the washing of the high-pressure cutting fluid. In this way, since there is no pressure difference in the chip removal outer rod, cutting fluid with a higher pressure (generally requiring 1~3MPa) is required to discharge the chips from the cutting area through the inner hole of the chip removal outer rod.

3. Ejector drill and internal chip removal

The cutting edges in the shape of the ejector drill are distributed alternately on both sides of the drill bit for precision parts processing. There are small holes for spraying cutting fluid in the neck and two trumpet-shaped holes in the front end. The chips are under the pressure of the high-pressure cutting fluid ejected from the small holes. Next, punch in from the two trumpet-shaped holes and suck out the hollow knife rod and discharge it outward.