Patent ID: 6953387

Claim:
A method of comparing the flow rate through one or more orifices in a workpiece, wherein each workpiece orifice is formed to resemble an orifice in a master part and wherein the flow rate through the one or more workpiece orifices is compared against the flow rate through the matching one or more orifices in the master part to determine whether or not the flow rate through the one or more workpiece orifices is within tolerance relative to the flow rate through the one or more master orifices comprising the steps of: a) forcing calibration fluid from a reservoir under pressure through the one or more orifices in the master part; b) forcing calibration fluid from the same reservoir under the same pressure through the one or more orifices in the workpiece; c) controlling the flow of fluid to provide an equal flow rate through the one or more orifices in the workpiece and the one or more orifices in the master part; and d) comparing the fluid pressure downstream of each the workpiece and the master part to determine whether or not the pressure differential is within predetermined limits indicating whether or not the flow rate through the one or more orifices in the workpiece are within tolerance.