Features and chip removal solutions for deep hole drilling machines

Processing characteristics of deep hole drilling machine

The continuous development of science and technology has driven the progress of all walks of life. In terms of machinery, the use of deep hole drilling is quite extensive. In deep hole processing, deep hole drilling machine tools are indispensable mechanical products, so what are the characteristics of deep hole drilling machine tools? If you don't know yet, follow Xiaobian to take a look.

1. The shank is constrained by the aperture, small diameter, large length, poor rigidity, low strength, and easy to oscillate, corrugate and taper during cutting, which affects the straightness and surface roughness of deep holes.

2. When drilling and reaming, the cooling and smoothing fluid is difficult to enter into the cutting area without the use of special equipment, which reduces the durability of the tool and makes chip removal difficult.

3. In the process of deep hole machining, you cannot directly investigate the cutting status of the tool. You can only judge by cutting sound, cutting chips, hand vibration, workpiece temperature, and appearance (oil pressure meter and electric meter) based on work experience. Is the cutting process normal?

4. The chip removal is difficult. It is necessary to choose a reliable method for chip breaking and control the length and shape of the chip to facilitate smooth removal and avoid chip blocking.

5. In order to ensure the smooth progress of deep holes in the machining process and reach the required processing quality, the chip (external) chip removal equipment, tool guidance and support equipment and high-pressure cooling smooth equipment should be added.

Generally, the hole depth is more than 3-5 times the hole diameter, which is called a deep hole.Its difficulty lies in chip removal and cooling.Drilling holes with a relatively small depth can be twisted. For smooth chip removal, the iron chips must be thin and straight. Channeled out and brought out smaller debris, the coolant simply entered together. The grinding method of the drill bit can be selected with a simpler grinding method.

1. The angle of the drill edge is increased to 130-140 degrees to add chip thickness and change the direction of chip discharge (the direction of chip discharge is straight with the edge)

2. Grind the cutting edge to reduce the axial cutting tool. A cutting edge at the cutting edge of the cutting edge will help chip separation.

3. If the drilling diameter is large, you can grind the chip groove on one side of the cutting edge and make it wider to balance the cutting forces of the two cutting edges.

4. Invert the outer edge of the cutting edge by a 45-degree angle of 1 mm to reduce wear and improve finish.

5. The speed of drilling is slightly lower, and the feed rate should be larger, so that the chips are thickened and discharged in a strip shape.

6. The nozzle of the coolant should face the hole inward so that the coolant can enter the cutting area.

When the hole warp ratio is larger than 8 times or more, it is best to drill on a special deep-hole drilling machine. The efficiency is very high. I have tried to produce a lathe spindle with a diameter of 32 and a length of about 850 mm. It is only 13 minutes for 45 steel.

Deep hole drilling is divided into two types: external chip removal and internal chip removal:

Outer chips are selected for smaller diameters, because the drill rod is too small to eject chips. The inner hole of the drill pipe with a relatively large diameter has sufficient space for chip removal. High-pressure oil is pressed between the hole wall and the drill pipe to discharge chips and heat from the rod. The drill is specially made of hard alloy, which is divided into two parts, the guide and the chip edge. The chip edge is ground into a trapezoidal trapezoid to divide the chip. The height and width of the chip breaker depends on the material and feed of the workpiece to ensure that the chip shape is Tight and small C-shaped or tile-shaped is preferred.