1, when measuring parts on the machine tool, to wait for the parts to stop completely, or not only make the measuring surface of the gauge premature wear and loss of precision, and will form an accident. Especially when the turner use external card, do not think the caliper is simple, wear a little does not matter, pay attention to the castings often have pores and shrinkage, once the foot falls into the pore, the operator's hand can be pulled in, forming a serious accident.
2, measurement should be measured before the measuring surface of the gauge and parts of the measured surface to wipe clean, to avoid the presence of dirt and affect the accuracy of measurement. With fine gauges such as vernier calipers, percentages and percent tables, etc., to measure the forging blank, or with abrasive (such as emery, etc.) of the appearance is wrong, so easy to make the measurement surface soon wear and lose accuracy.
3, the gauge in the use of the process, do not and things, tools such as files, hammers, turning tools and drill number stacked together, so as not to bruise the gauge. Do not just put on the machine tool to avoid the machine tool oscillation and make the gauge fall down damage. Especially vernier calipers, etc., should be placed flat in a special box, so as not to deform the body of the ruler.
4, the gauge is the measurement of things, certainly not as a substitute for other things. For example, take the vernier caliper scribe line, take the percentage ruler as a small hammer, take the steel ruler as a screw screw driver, as well as the steel ruler to clean up chips, etc. are wrong. The gauge as a toy, such as the percentage rule in the hands of arbitrary waving or shaking, etc. is also wrong, are easy to make the gauge lose accuracy.
5, the temperature has a great impact on the measurement results, the fine measurement of parts must make parts and gauges are measured at 20 ℃. Usually can be measured at room temperature, but it is necessary to make the workpiece and the gauge temperature consistent, otherwise, due to the characteristics of the thermal expansion and contraction of metal materials, so that the measurement results are not accurate. Temperature also has a great impact on the accuracy of the gauge, the gauge should not be placed in the sun or on the bedside box, because the temperature of the gauge increases, but also can not measure the exact scale. Do not put the fine gauge in the vicinity of heat sources (such as electric furnaces, heat exchangers, etc.) to avoid heat deformation of the gauge and loss of precision.