The application of piston-like stereometer to mass flowmeter calibration has been limited by the fact that it is small in volume but complicated in structure and that the tested volume needs to be accurately converted into mass flow. 活塞式小体积管因为体积小,结构复杂,检测的体积需要非常准确的转换成质量流量,制约了活塞式小体积管在检定质量流量计方面的发展。