Gross leak measurement in an incompressible test item in a film chamber

Abstract

The invention relates to a method for the gross leak measurement of an at least partially incompressible test object () in a film chamber () that comprises at least one flexible wall region and is connected, in a gas-conducting manner, to a pressure sensor (), a vacuum pump () and, by way of a calibration valve (), to a calibration chamber () enclosing a calibration volume (), comprising the steps of evacuating the film chamber (), measuring the pressure curve within the film chamber () after the evacuation is completed, connecting, in a gas-conducting manner, the calibration volume () to the inner volume of the film chamber () during the measurement of the pressure curve, the pressure being measured before the gas-conducting connection is established, and with the gas-conducting connection established, to the film chamber (), and the pressure in the calibration chamber () prior to the connection to the film chamber () being higher or lower than the pressure in the film chamber (), characterized in that the pressure difference Δpbetween the pressure before the gas-conducting connection is established and the pressure with a gas-conducting connection to the film chamber (), in the case of an empty film chamber () comprising no test object (), is compared to the corresponding pressure difference Δpwhen a test object () is present in the film chamber ().