Research on the characteristics of front and rear angles of CNC lathes

For a CNC machining factory, the most direct way to effectively reduce the cost of CNC lathes is to effectively use CNC lathes to machine different parts of the tool. When choosing CNC machining tools, in addition to considering the selection of tool materials, it is also necessary to understand the role of the rake and relief angles of the tool in the machining process.

CNC lathe machining tool rake angle

Generally speaking, the rake angle has a great influence on cutting force, chip discharge and tool durability. These factors are as follows:

1. The positive rake angle is large and the cutting edge is sharp;

2. The cutting force decreases by 1% for each degree of rake angle increase;

3. If the positive rake angle is too large, the edge strength will be reduced; if the negative rake angle is too large, the cutting force will increase.

The rake angle of CNC lathe can be divided into: 1. Large negative rake angle; 2. Large positive rake angle;

1. The large negative rake angle is generally used for cutting hard materials; the cutting edge is required to have strong strength to adapt to the processing conditions of intermittent cutting and cutting the surface layer containing black skin.

2. A large positive rake angle is generally used for 1) cutting soft materials, easy-to-cut materials, processing materials and poor machine tool rigidity.

Let's talk about the advantages and disadvantages of rake cutting with CNC tools.

1. Advantages of rake angle cutting: The use of rake angle cutting can reduce the resistance encountered in cutting, thereby improving cutting efficiency; using rake angle cutting can reduce cutting temperature and vibration, and improve cutting accuracy; Tool wear increases tool life; using rake cutting reduces tool wear and increases edge reliability when selecting the correct tool material and plunge angle.

2. Disadvantages of too large rake angle: Since increasing the rake angle will reduce the angle at which the tool cuts into the workpiece and the cutting efficiency, when cutting workpieces with high hardness, if the rake angle is too large, the tool will be very difficult to cut. It is prone to wear and even chipping; if the tool material is weak, it is difficult to maintain the reliability of the cutting edge.

CNC CNC lathe machining tool clearance angle

Generally speaking, the clearance angle reduces the friction between the back of the tool and the workpiece, so that the tool can cut freely artifact. These factors are as follows:

1. The larger the clearance angle, the less positive wear of the blade;

2. The larger the clearance angle, the lower the strength of the blade tip.

The relief angle of CNC machine tools can be divided into: 1. Small relief angle; 2. Large relief angle.

1. Small relief angle is generally used for cutting hard materials, requiring high cutting strength.

2. The large relief angle is generally used for cutting soft materials, and it is easy to cut hard materials when cutting.

Based on this, this paper introduces the advantages and limitations of back corner cutting of CNC lathe machining tools.

1. Advantages of clearance angle cutting: Large clearance angle cutting can reduce the wear of the flank face, so it is better to use a smaller clearance angle cutting without a significant increase in rake angle loss In general, when the cutting ductility is good and the material is soft, fusion is more likely to occur. The dissolved knot will increase the clearance angle and the contact surface of the workpiece, increase the cutting resistance, and reduce the cutting accuracy. Therefore, this phenomenon can be avoided by cutting with a larger clearance angle when cutting such materials.

2. Restriction of clearance angle cutting: When cutting materials with low heat transfer capacity such as titanium alloy and stainless steel, the use of large clearance angle to cut the rake face is prone to wear and even tool damage. Therefore, when cutting such materials, a large relief angle is not suitable; although using a large relief angle can reduce the wear of the flank, it will accelerate the degradation of the cutting edge. Therefore, the cutting depth will be reduced accordingly, thus affecting the cutting accuracy. In order to achieve this purpose, technicians need to adjust the angle of the tool regularly to maintain the cutting accuracy; when cutting high-hardness materials, if the clearance angle is too large, the resistance encountered during cutting will cause the rake angle to be subjected to a strong compressive force. resulting in defects or damage.