Three points for attention in precision CNC machining
Precision mold manufacturing companies should standardize the correct operation of CNC machine tools by technicians.CNC technicians are responsible for the processing of mold parts as required to ensure the safety of production and the maintenance of machine tools to extend the service life of machine tools.There are three things to watch for.
1. Notice 1 after the machine is powered on
1) after the machine is energized, check whether the switches and buttons are normal and flexible.
2) check whether the voltage, oil pressure and air pressure are normal, and manually lubricate the parts with manual lubrication first;
3) after the machine is started, the reference point (the machine's origin) is manually returned to each coordinate axis.If an axis is at the zero before it is at the reference point, it must be moved to a position more than 100mm away from the origin, and then manual back to the reference point or control the machine tool to move forward in negative direction to make it return to the reference point.
4) there shall be no foreign matter on the platform, cover or guide rail during the table rotation exchange;
5) after the input of NC program, it should be carefully calibrated to make sure there is no error.Including code, instruction, address, numeric value, positive and negative number, decimal point and syntax check;
6) install and locate the fixture according to the process procedures;
7) correctly measure and calculate the workpiece coordinate system, and verify and check the results;
8) input the workpiece coordinate system to the offset page, and carefully check the coordinates, coordinate values, positive and negative Numbers and decimal points;
9) after the cutter compensation value (length, radius) is input into the offset page, the cutter compensation number, compensation value, plus or minus number and decimal point should be carefully checked.
2.Note 2 in the process of workpiece processing
1) when high-precision workpiece forming, use the micrometer to test the cutter on the spindle, so that its static beating is controlled within 3 sliding m. If necessary, the clamping system should be reinstalled or replaced
2) for the parts that are first machined, or the parts that are repeatedly machined periodically, the check and check of the piece-by-piece procedure must be carried out according to the drawing process, procedure and cutter adjustment card before machining.
3) the fast multiplier switch must be placed at a lower level during single section test cutting;
4) when each knife is used for the first time, it must first verify whether its actual length is consistent with the compensation value given;
5) in the process of program operation, focus on several kinds of display on the numerical control system;
6) coordinate display: the position of the cutter movement point in the machine tool coordinate system and the workpiece coordinate system at present can be understood, the amount of motion of this program section and the amount of remaining motion can be understood, etc.;
7) register and buffer register display: you can see the contents of each state instruction and the next program segment being executed.
8) main program and subroutine display: can understand the specific content of executing program segment.
9) dialog display (Custom)
10) during the trial cutting feed, when the cutter runs to the surface of the workpiece at 30~50mm, it must be kept at the low speed feed to verify that the remaining coordinate axis coordinates and X and Y coordinates coordinates are consistent with the drawing;
11) adopt the "progressive" method for some knives with test requirements.For example, to bore a hole, you may first try boring a small length, after passing the test, then boring to the entire length.The cutter data with the tool radius compensation function can be modified from large to small.
12) during the trial cutting and machining, it is necessary to re-measure the length of the cutter after replacing the cutter and auxiliary tools, and to revise the compensation value of the cutter and the compensation number of the cutter.
13) during program retrieval, it shall pay attention to whether the position of cursor is reasonable and accurate, and observe whether the coordinate of cutter and machine motion is correct;
14) after the procedure is modified, the modification part must be carefully calculated and carefully checked;
15) during manual feeding and manual continuous feeding, it is necessary to check whether the positions selected by various switches are correct, make clear the positive and negative directions, confirm the buttons and set feeding speed or pulse multiplier, and then operate.
3. Matters needing attention: after finishing the work piece
1) after the entire batch of workpieces have been processed, the cutter number and tool compensation value should be checked to make the compensation value of cutter number and cutter completely consistent in the procedures, offset pages, adjustment CARDS and process CARDS;When the tool is used again, the tool should be re-used on the tool counter, which can effectively reduce the impact of tool wear on the workpiece.
2) remove the cutter from the tool store, and clean the number according to the adjustment card or procedure.Complete storage of disk, process and cutter adjustment CARDS;
3) remove the fixtures. Some fixtures shall record the installation position and orientation, and record and keep records;
4) place each coordinate axis in the middle position;
5) at this time, if it is necessary to shut down, press the power disconnection button on the operation panel and wait for a moment, so that the main shaft cooling oil in the main shaft can be shut down automatically after backflow.