Abstract:A novel apparatus is developed to calibrate vacuum gauge for its response characteristic, which consists of calibration system, highspeed data acquisition and control system, pumping system, baking system, and gas supply system. A very fast opening ultrahigh vacuum gate valve and flow restriction element of various dimensions are combined to realize controllable standard pressure establishment time ranging from 1812 ms to 65813 ms. Moreover, to establish transient step over three orders of magnitude of the dynamic vacuum pressure, a volume ratio of 1 5739 between downstream chamber and upstream chamber is employed. Through numerical simulation of the rapid expansion process of rarefied gas in the millisecond range, the function between conductance and time under different flow states is obtained. Experiments are conducted on capacitance diaphragm gauges with optimized response time (107 ms). The result show that the calibration range of the apparatus is between 10-1 and 105 Pa, with a combined standard uncertainty of 14%.