许多大型的尤其是采用静压导轨的精密机床,它们的床身导轨长度往往达十几米甚至几十米,这类机床在安装时通常要求床身导轨与大地的水平度很高。一般的机床生产厂家通常采用水平仪来测量床身导轨的水平度,但是普通水平仪的测量精度一般为每格0.02/1000,对尺寸较长的床身导轨其累积误差会变得很大,无法满足床身导轨高精度的测量要求。 Many large, especially the use of hydrostatic guide precision machine tools, their length of the bed rails are often up to ten meters or even tens of meters, such machines usually require installation of the bed rails and the ground level is high. General machine tool manufacturers usually use the level to measure the level of bed rails, but the general level of measurement accuracy is generally 0.02 / 1000 per bed, the longer the length of the bed rail its cumulative error will become very large, can not meet Bed rails high-precision measurement requirements.