| 摘要 |
PROBLEM TO BE SOLVED: To provide a flow rate calibration unit capable of calibrating a flow rate by replacing a plurality of gas integration units.SOLUTION: A flow rate calibration unit 1 calculates a volume V between flow rate control valves 125A-125C and a second isolation valve 105 by using a pressure fluctuation value per unit time of pressure measurement values measured by a pressure gage 103, with the second isolation valve 105 closed, and a temperature measurement value measured by a temperature gage 104, and calibrates flow rates of mass flow controllers 124A-124C one by one. A first calibration-side connection part 2 for detachably connected to the gas integration unit 20 is provided on an upstream side of the pressure gauge 103. A calibration gas input valve 10, a calibration-side mass flow controller 11, and a calibration-side flow rate control valve 12 that are connected in series are provided in parallel to the second isolation valve 105.SELECTED DRAWING: Figure 1 |
