When machining CNC lathe parts, cutting off the workpiece is the most indispensable process, and the cutting groove on the workpiece is also the most common. The efficiency of cutting and grooving is inseparable from the rigidity of the machine tool. The rigidity of spindle and turret of CNC lathe are the main reasons affecting the vibration of workpiece. In addition, the cutting method in cutting and grooving is also the most critical. In this guide, we discuss how to improve the efficiency of cutting and grooving workpiece processing.
1. Common methods of turning groove
The common methods of getting on the groove on the workpiece surface are outer groove, inner groove and end groove.
2. Selection of grooving cutter
High speed steel grooving cutter is generally used for grooving.
3. Method of turning groove
For rectangular grooves with low turning accuracy and narrow width, the groove turning tool with tool width equal to the groove width can be used, and the straight in method can be turned out at one time.
Rectangular grooves requiring high turning accuracy are generally turned in two times. The groove can be turned to a certain width by the fine turning method, and then the groove can be cut to a certain depth by the fine turning method, and then the groove can be cut on both sides according to the size of the groove. Turning small circular arc groove is generally turned with forming turning tool; Turning large circular arc grooves can be carried out with both hands, and the sample plate can be used for inspection and trimming. Turning small trapezoidal grooves is generally completed with forming turning tools. Turning a large trapezoidal groove is usually completed by turning the straight groove first, and then using the trapezoidal knife straight forward method or left-right cutting method.
4. Inspection and measurement of rectangular groove
Grooves with low accuracy requirements are generally measured with steel ruler and caliper. For grooves with high accuracy requirements, micrometer, sample plate, plug gauge and vernier caliper can be used for inspection and measurement.
The cutting knife should be used for cutting. The shape of the cutting knife is similar to that of the grooving knife, but the knife head is narrow and the dagger is easy to break. Cutting knives include high-speed steel cutting knives, cemented carbide cutting knives, elastic cutting knives, reverse cutting knives and other types.
There are several cutting methods for CNC lathe:
1. Straight forward method
The cutter feeds perpendicular to the axis of the workpiece. This method has high efficiency, but it has high requirements for the grinding and clamping of lathe and cutting knife, otherwise it is easy to break the knife head.
2. Left and right knife borrowing method
In the case of insufficient rigidity of cutting tools, workpieces and lathes, the tool borrowing method can be used to cut off workpieces. This method means that the cutter moves back and forth repeatedly in the axis direction, and then feeds radially on both sides until the workpiece is cut off.
3. Reverse tangent method
The reverse cutting method refers to the reverse clamping of the workpiece and the turning tool. This cutting method is suitable for cutting workpieces with large diameter. Its advantages are: because the cutting force acting on the workpiece is consistent with the gravity direction of the spindle (downward), the spindle is not easy to jump up and down, it is relatively stable when cutting the workpiece, and the chips are discharged downward, which will not be blocked in the cutting groove, and the chip removal is smooth.