What should I pay attention to when solving the problem of CNC lathe collision?

Tool collision refers to a machine accident in which the tool (including tool holder, trailer, etc.) accidentally collides with the workpiece, chuck or tailstock during the movement. For novice CNC lathe operators, tool collision is the most likely accident. Once a tool collision accident occurs, the accuracy of the machine tool will be the least affected, and the damage of the machine tool will be more severely affected. The operator must attach great importance to it.

In order to prevent the knife from colliding, it is recommended to do a good job in two aspects: the operator and the programming.

Pay attention to the following points in operation

(1) Always check whether the position of the machine tool limit block is correct and whether it is loose; (but it should be noted that the machine tool limit can only play a protective role in the limit position of the stroke, because the tool extension position is different, and the workpiece blank size is different. In most cases, the limit block of the machine tool cannot effectively prevent the impact of the tool during the machining process.

(2) After the program input is completed, carefully check whether there is any error, so as to avoid collision caused by the wrong coordinate number input.

(3) For correct tool setting and tool compensation, it should be noted that the Z-direction zero used in tool setting should be unified with the Z-direction zero used in programming, so as to avoid tool collision caused by inconsistent workpiece coordinate system settings.

(4) When running at the beginning stage, set the fast multiplier slowly (for example, it can be set to 25%).

(5) After programming, the program should be debugged in a separate part, and the display should be switched to a page where the workpiece coordinate system and program execution can be seen at the same time.

(6) During the debugging process, always pay attention to the current absolute coordinate value and the end coordinate position of the next block to determine the distance of the tool movement, and then observe the distance between the current tool position and the workpiece position to determine whether a collision may occur , And specify the following two points:

Pay special attention to the first G00 movement command in the program (and the first G00 movement command after tool change). There have been many collision accidents with tool holders in this project. When running this program segment, place your left hand on the "feed and hold" button, and press "pause" if necessary.

If you are unskilled, you can set the first G00 coordinate far away from the blank, and then position the second G00 to the initial processing position, so that problems can be found when a single segment is running.

The following part of the program is the tool replacement instructions. The extension length of the relevant tool must be considered to ensure that there will be no tool collision when the tool holder rotates before the next block can be run.

(7) If GSK980 series products use G50 to set the tool setting coordinates, you must pay attention to the possibility that the absolute coordinates may return to the initial value after returning to the mechanical zero point, which may cause an accident. Medieval Star 18 uses the Absolute Knife patch. Please do not use the coordinate system setting command arbitrarily.

(8) If the tailstock must be used for processing, the impact limit position of the electric tool holder and the tailstock in the X direction and the trailer and the tailstock in the Z direction must be considered when installing the tools. (If the tailstock is not used for a long time, it is recommended to temporarily remove the tailstock to avoid collision)

Please pay attention to the following points when writing programs

(1) The first movement command in the program or the first movement command after each tool change command must be the absolute coordinate positioning of X and Z coordinates.

(2) When exiting the tool with G00 command before tool change, the relative relationship between the actual extension position of the relevant tool and the workpiece blank must be fully considered to ensure that the tool holder does not collide when rotating (for example, the boring tool can be extended).

(3) When cutting threads, the moving speed of the tool post should not exceed the allowable speed of the servo motor. It is recommended that the spindle speed * lead does not exceed 3000 mm/min.

(4) Do not use the coordinate system blindly to set instructions in the program (such as GSK G50).

(5) It is recommended to use simulation software to debug the program on the computer, and then transfer it to the machine tool to avoid possible errors during program input.