Device for sampling working liquids of industrial machines

Device for sampling working liquids of industrial machines, comprising a container having an aperture and a closing member engaged to said aperture for fluid-tight sealing same aperture;

• wherein the pressure inside said container is sufficient to withdraw a working liquid from a machine and ranges from about 6000 Pa to about 60000 Pa;
• wherein said closing member includes a shutoff element switchable between a closing position in which said container is fluid-tight sealed and an opening position in which said container is in fluid-communication with the outside environment;
• wherein said closing member includes a screw plug engaged to said aperture of said container, said screw plug having a flat top surface, said shutoff element being adapted to said screw plug and includes a first threaded end screwed in a threaded hole of said flat top surface of the screw plug to provide a fluid-tight seal;
• and
• a lid removably engageable onto said container;
• said lid covering said screw plug and said shutoff element so as to make said screw plug and said shutoff element fully inaccessible.