A bailer suction, particularly for an electrode cooling system of a welding robot.

Device 21 of suction cylinder for a fluid circuit, on either side of a removable load 2: - an upstream pipe 13, and a downstream pipe 14, - a supply conduit 11 and a conduit discharge 12, - a stop valve 17 disposed to isolate the upstream conduit with the supply line, and - a stop valve 18 to isolate the downstream pipe of the discharge pipe with - the fluid being maintained substantially at an inlet pressure P1 in the supply line and an output pressure P2 in the discharge pipe, the inlet pressure being greater than the outlet pressure, characterized in it comprises a suction cylinder 24 controlled by the pressure difference between the supply line and the discharge line.