Materials will expand and contract with heat. In precision machining, the temperature problem must not be ignored! Temperature difference is the enemy of accuracy. If we don't care about the important issue of temperature, how to discuss accuracy? Because most of the machine components are steel and cast iron, the shape and length of the machine will change according to room temperature and the heat generated by the machine itself!
01 The effect of temperature changes on the length of the material
The specific amount of thermal expansion and contraction of the material depends on the change value of the material and temperature. The following provides a table of the expansion coefficients of steel and copper. For example, the linear expansion of steel is a change of 12μm per meter of length when the temperature changes by 1°C.
For example:
Workpiece length: 200 mm
Temperature change: 10℃
Expansion value: 0. 02 mm
For example:
Electrode length: 200 mm
Temperature change: 10℃
Expansion value: 0.05 mm
Temperature causes detection error
If the workpiece and the inspection instrument and gauge used in the inspection are made of different materials and are not under the standard temperature condition during the inspection, the deviation of 20°C from the standard temperature will always be an important factor in the detection error.
Detection error due to temperature
For example, heating a 100mm-long steel block gauge for 4C, such as heating with the temperature of the palm of the hand, will cause a length change of 4.6μm.
