1.Temperature

(1) Temperature is the biggest factor affecting the accuracy of the measuring machine.

(2) The temperature in the machine room of the measuring machine is gradually increased from the bottom to the top, and the temperature changes every moment. Therefore, the difference between the grating temperature and the part temperature of each axis affects the accuracy of the measurement of the measuring machine.

(3) Unreasonable temperature control method (air conditioning is ready to use, and the measuring machine is not used to turn off the air conditioner), which will lead to unstable and balanced temperature in the measuring chamber. The temperature of the measuring machine is also constantly changing, the machine is in an unstable state and the measurement accuracy will be poor.

Solution and requirements

(1) Linear correction and temperature correction can be used in the measuring machine software to correct the temperature influence for the environmental conditions of the on-site inspection.

(2) Electrical equipment, computers and other heat sources should be kept at a certain distance from the measuring machine.

(3) The air conditioner should try to select the inverter air conditioner with strong temperature control capability. The installation position of the air conditioner should be reasonably planned. The air-conditioning wind direction is forbidden to be directly blown onto the measuring machine. Due to the temperature difference between the upper and lower sides of the measuring chamber, the wind direction should be adjusted upward to make the air form a large cycle, and the indoor air temperature is kept balanced.

(4) Turn on the air conditioner every morning when you go to work, and turn off the air conditioner when you get off work at night.

(5) The machine room should have insulation measures, and the doors and windows should be closed to reduce the loss of temperature and avoid sunlight.

(6) Strengthen the management of the measurement room, and do not have extra staff to stay.

2. Correctness of equipment accuracy compensation file

The device accuracy compensation file record is used to record the device accuracy error data, and the measurement software is based on it for error compensation. If you forget to install the compensation file or lose the backup compensation file when installing the measurement machine software, the measurement accuracy of the measurement machine will be poor, and the machine accuracy needs to be re-verified.

Solution and requirements

Keep the backup compensation file and install the compensation file.

3. Correctness and accuracy of three-coordinate probe calibration

When the probe is inspected, the unqualified check ball and stylus are not secure, and the wrong stylus length and standard ball diameter are input, so that the compensation error or error occurs when the software calls the probe compensation file during measurement, which affects the measurement accuracy. Incorrect stylus length and standard ball diameter will cause compensation error or error when the software calls the probe compensation file during measurement, which will affect the measurement accuracy and even cause abnormal collision of the device and cause damage.

Solution and requirements

(1) Keep the standard ball and stylus clean.

(2) Ensure that the measuring head, the probe, the stylus and the standard ball are firmly fixed.

(3) Enter the correct stylus length and standard ball diameter.

(4) According to the shape error and the corrected diameter and repeatability of the gem ball, the accuracy of the correction is judged (the length of the gem ball after the length of the lengthened rod is different).

(5) When using different probe positions, after correcting all the probe positions, check the calibration accuracy by measuring the coordinates of the standard ball center point.

(6) The probe should be re-calibrated in the case of the probe, the stylus movement and the high measurement accuracy requirements.

4. The shape error of the tested part and the correct choice of the reference

(1) When the measured part has obvious burrs or trachoma, the repeatability of the measurement is significantly deteriorated, so that the operator cannot give accurate measurement results.

(2) The selection of an incorrect measurement reference will cause errors in measurement and calculation results.

Solution and requirements

Choose the correct measurement baseline.