Each step may seem insignificant, but any one of them cannot be missed.
1. After the machine tool is powered on
Precautions are as follows:
1. After the machine tool is powered on, check whether the switches and buttons are normal and flexible, and whether there are any abnormalities in the machine tool;
2. Check whether the voltage, oil pressure and air pressure are normal, and the parts with manual lubrication should be manually lubricated first;
3. After the machine tool is turned on, each coordinate axis manually returns to the reference point (machine tool origin). If an axis is at the zero position before returning to the reference point, the axis must be moved to a position 100mm away from the origin, and then manually return to the reference point or control the machine tool to move in the negative direction of the stroke at this position to return it to the reference point;
4. When performing the worktable rotation exchange, there must be no foreign matter on the table, the shield and the guide rail;
5. After the CNC program is input, it should be carefully proofread to ensure that it is correct. This includes checking codes, instructions, addresses, values, signs, decimal points and syntax;
6. Install and locate the fixture according to the process specifications;
7. Correctly measure and calculate the workpiece coordinate system, and verify and check the results;
8. Enter the workpiece coordinate system into the offset page, and carefully check the coordinates, coordinate values, signs and decimal points;
9. After the tool compensation value (length, radius) is entered into the offset page, the tool compensation number, compensation value, sign and decimal point must be carefully checked.
2. During the workpiece processing
Precautions are as follows:
1. When performing high-precision workpiece forming, use a micrometer to detect the tool on the spindle to control its static runout within 3µm. If necessary, re-clamp or replace the tool clamp system;
2. Whether it is a part that is processed for the first time or a part that is repeatedly processed periodically, before processing, it must be checked and verified according to the drawing process, program and tool adjustment card for each tool and each program;
3. When cutting a single section, the fast rate switch must be set to a lower level;
4. When each tool is used for the first time, it must be verified whether its actual length matches the given compensation value;
5. During program operation, it is important to observe several displays on the CNC system.
(1) Coordinate display: You can understand the current position of the tool movement point in the machine tool coordinate system and the workpiece coordinate system, understand the movement amount of this program segment, how much remaining movement there is, etc.
(2) Register and buffer register display: You can see the status instructions of the program segment being executed and the content of the next program segment;
(3) Main program and subroutine display: You can understand the specific content of the program segment being executed;
(4) Dialogue display screen (Custom): You can understand the current spindle speed, current cutting feed speed, spindle cutting feed per revolution, current spindle cutting load and each stroke axis load of the machine tool, and can calculate the corresponding tool cutting amount per blade from the spindle cutting feed per revolution.
6. When testing the cutting feed, when the tool moves to 30~50mm on the workpiece surface, it must be maintained at a low speed feed to verify whether the remaining coordinate values of the coordinate axis and the X and Y axis coordinate values are consistent with the drawing;
7. For some tools that require trial cutting, the "gradual" method is used. For example, when boring a hole, you can first try boring a small length, and then bore the entire length after passing the test. The tool data using the tool radius compensation function can be modified from large to small while trial cutting;
8. During trial cutting and processing, after replacing the tool and auxiliary tools, be sure to re-measure the tool length and modify the tool compensation value and tool compensation number;
9. When searching the program, pay attention to whether the cursor position is reasonable and accurate, and observe whether the tool and machine tool movement direction coordinates are correct;
10. After the program is modified, the modified part must be carefully calculated and carefully checked;
11. When operating hand-crank feeding and manual continuous feeding, it is necessary to check whether the selected position of various switches is correct, clarify the positive and negative directions, identify the buttons and the set feed speed or pulse ratio, and then operate.
3. After the workpiece is processed
The precautions are as follows:
1. After the whole batch of workpieces is processed, the tool number and tool compensation value should be checked to make sure that the tool number and tool compensation value in the program, offset page, adjustment card and process card are completely consistent; when the tool is reused, it should be re-calibrated on the tool setting instrument to effectively reduce the impact of tool wear on the workpiece;
2. Remove the tool from the tool magazine, clean the number and put it into the warehouse according to the adjustment card or program. The disk and process and tool adjustment card are put into the warehouse as a set;
3. Remove the fixture. The installation position and orientation of some fixtures should be recorded, and records should be made and archived;
4. Stop each coordinate axis in the middle position;
5. If you need to shut down the machine at this time, press the power disconnect button on the operation panel and wait for a while to allow the spindle cooling oil in the spindle to partially reflux before shutting down automatically.
