Patent ID: 9638560
Date: 2017-05-02
CPC Classifications: G01F,G05D,Y10T

Claim:
1. A calibration method for a flow rate controller for a gas supply device that supplies a plurality of kinds of gases to a gas use portion in a switchable manner through each of a plurality of flow rate controllers, respectively, wherein the method comprises the steps of: (a) providing a flow rate controller calibration unit that includes a build-up tank provided with an inner volume, a first inlet side on-off valve and a first outlet side on-off valve of the build-up tank, and a gas pressure detector and a gas temperature detector arranged to detect gas pressure and gas temperature for gas inside the build-up tank, wherein the flow rate controller calibration unit is joined in a branched form to a gas supply line of the gas supply device, and the first outlet side on-off valve of the flow rate controller calibration unit is connected to a vacuum exhaust system; (b) then first, closing a plurality of second outlet side on-off valves of each of the flow rate controllers of the flow rate control device and closing a second inlet on-off valve of the gas use portion, and the first outlet side on-off valve and the first inlet side on-off valve of the calibration unit are opened; (c) and next, only a third outlet side on-off valve of a flow rate controller to be calibrated is opened to flow gas into the calibration unit at a set flow rate, and after the gas flows into the build-up tank, performing a first gas temperature T (d) and then, at a time t (e) and then, at a time t (f) by comparing a set gas flow rate and the calculated gas flow rate Q, a flow rate calibration of the flow rate controller to be calibrated is performed.