How to choose a good deep hole gun drill bit?

CNC Tools Deep hole drill end mill milling cutter foshan yunsheng

The single-edged gun drilling process is characterized by the fact that coolant is injected through the coolant hole in the tool and is expelled from the drilled hole together with chips in the V-shaped groove (groove) on the drill rod. The coolant also provides lubrication to the periphery of the drill bit.



Gundrilling system



Deep hole drilling refers to the processing method of holes with an aspect ratio greater than 5, and the hole diameter covers from 2mm to 20cm.
The main tools used include BTA drills and gun drills.
The gun drill is a typical inner tube for conveying cutting fluid, and a V-shaped groove outside the tube for chip removal and double-edged cutting.
The drill bit of the gun drill is welded to the drill pipe, and the bit needs to be sharpened regularly. The clamping position is far away from the cutting edge, and the torque transmission effect is not ideal.
The BTA drill adopts the internal chip removal method, and the cutting fluid is delivered outside the drill bit.
The BTA drill can cut multiple edges with staggered teeth, and has a better chip removal path (internal chip removal), allowing the input of a large flow of cutting fluid for chip removal. Most of the currently used BTA knives use carbon steel substrates, detachable, multi-headed diamond blades or powder alloy blades, and the economic benefits are relatively high.
Generally speaking, the special cross-section of the gun drill pipe makes the gun drill less rigid than the cylindrical BTA drill pipe. But the gun drill performs much better than BTA in deep hole drilling with small diameter

Welded Carbide Gun Drill For CNC Machining

1.Welded Carbide Gun Drill

The gun drill consists of three parts, the main cutting action is done by hard alloy, and the drive handle and tool holder are the power torque transmission parts. Appropriate gun drill selection will bring twice the result with half the effort, and can also reduce manual labor. Welded gun drills are generally selected when processing small-diameter deep holes, and welded gun drills and machine-clamped gun drills can be used selectively when processing large-diameter deep holes. Which gun drill bit to use, including imported or domestic, welded or machine-clamped, I think it is best to choose the right one according to local conditions, specific analysis of specific conditions, and different working conditions and hardness of processed materials.

DeepTriDrill Indexable-Insert Gundrills -Foshan yunsheng

2.Indexable Inserts Deep Hole Drill

Indexable-insert gundrill features one insert and two guide pads oriented in an optimized position on the drill head. This achieves tight tolerances with circularity and straightness, as well as a fine surface finish, which a brazed gundrill could traditionally attain. The insert incorporates chipsplitters on the chipbreaker geometry, which break chips into smaller pieces to facilitate chip evacuation and reduce cutting force, enabling a higher feed rate than traditional gundrills. The coated insert and guide pads also allows indexable-insert gundrill to reach higher cutting speeds, which has been difficult with brazed gundrills.

indexable-insert gundrill not only increases machining performance but also facilitates inventory management thanks to its indexable system. This small-diameter range expansion complements indexable-insert gundrill, further enhancing its product positioning in the deep-hole drilling market for high productivity and economy.


3.BTA Drill Bits

BTA drilling tool heads are threaded or mounted onto long drill tubes, and use multiple cutting surfaces on a single tool to remove chips efficiently, exhausting them using high-pressure coolant through holes in the tool head, then out the drill tube and through the machining spindle. BTA tooling is available in brazed or inserted carbide configurations.


CNC deep hole drilling tools are mainly suitable for drilling positions requiring deep holes in mold manufacturing, machinery industry, automobile industry, aerospace, power generation equipment, etc. The deep hole drilling machine not only improves the efficiency of the drilling depth, but also improves the quality of the deep hole process. Excellent results have been achieved in the development of large, medium, small, super large and heavy CNC deep hole drills, traditional horizontal, new vertical, vertical gantry and other deep hole drills. Today, CNC deep hole drilling has spread all over towns, accelerating the development of social progress and promoting scientific and technological progress

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