Abstract: A method for determining a functioning of a gas bleed valve in a primary reservoir for a medium for a hydraulic system includes connecting a testing apparatus with a separate reservoir of the medium to the primary reservoir; pumping the medium from the separate reservoir to the primary reservoir; measuring the volume of the medium pumped from the separate reservoir to the primary reservoir; and determining the functioning of the gas bleed valve by comparing the volume of the medium pumped to the primary reservoir with: a change of the medium volume measured in the primary reservoir, or a change of the pressure of the medium pumped to the primary reservoir.

Abstract: The invention relates to a method for determining a functioning of a gas bleed valve in a primary reservoir for a medium for a hydraulic system. The method comprising: connecting a testing apparatus with a separate reservoir of the medium to the primary reservoir; pumping the medium from the separate reservoir to the primary reservoir; measuring the volume of the medium pumped from the separate reservoir to the primary reservoir; and, determining the functioning of the gas bleed valve by comparing the volume of the medium pumped to the primary reservoir with: a change of the medium volume measured in the primary reservoir, or a change of the pressure of the medium pumped to the primary reservoir.

Abstract: The invention provides a method for determining the amount of undissolved gas present in a hydraulic system by supplying hydraulic medium thereto under overpressure, one of the parameters Pressure (P) and Volume (V) being set during this supply and the course of the variation of the other parameter (Volume (V) or Pressure (P)), which is dependent thereon and on the amount of undissolved gas, being recorded; the detection results are then compared with those which were calculated and/or are known for a reference system which corresponds to the system and is subjected to the same treatment when the hydraulic medium present therein contains no dissolved gas or a known amount of dissolved gas; from this comparison results an indication of the amount of undissolved gas, and also of its location, in the system.