正确合理的选用量具是保证产品零件质量的重要条件之一。但选择量具要考虑多方面的因素。例如,测量误差和加工误差之间的分配,被测对象的精度要求,结构尺寸的大小、形状、重量和所用的材料,加工的工艺条件、批量、使用测量器具的精确度和经济性等等。因此选择量具是一个比较复杂的问题。要正确合理地选用量具,必须根据实际情况进行具体分析。本文以保证测量精度为前题,并考虑经济,操作使用方便等问题,介绍两种选择量具的方法。一、根据零件允许的测量误差选择量 Correct and reasonable selection of measuring tools is one of the important conditions to ensure the quality of product parts. However, the choice of measuring tools to consider many factors. For example, the distribution between measurement error and machining error, the accuracy of the measured object, the size of the structure size, shape, weight and materials used, processing conditions, batch, accuracy and economy of the measuring instruments used . Therefore, the choice of measuring tools is a more complicated issue. To correctly and properly use measuring tools, we must conduct a specific analysis based on the actual situation. In this paper, to ensure the accuracy of measurement as the title, and consider the economy, ease of use and other issues, introduce two methods of measuring tools. First, according to the measurement of the part allows the choice of error