Electrode assembly for electromagnetic flow sensors

An electrode assembly comprising:

• a measuring tube made of a metallic, nonferromagnetic material having a tube wall with an external surface, the measuring tube being lined with an insulating material, the measuring tube having a hole in the tube wall;
• an insulating body having a disk-shaped portion, a lower neck and a tubular extension, the tubular extension extending into the hole in the tube wall, the lower neck being disposed between the disk shaped portion and the tubular extension;
• a measuring electrode having a head and a shank, the shank having an external thread and having a smaller diameter than the head, said measuring electrode being fitted in the hole of the tube wall, the head engaging the insulating material lining the measuring tube, and the shank extending through the insulating material lining, and the insulating body, thereby insulating the measuring electrode from the tube wall;
• a cylindrical part made of an electrically insulating, hydrophobic material and having a bottom portion and a wall portion, said bottom portion having a central opening with a diameter, said wall portion having an inside diameter greater than the diameter of the central opening, the diameter of the central opening being less than a diameter of the disk-shaped portion of the insulating body, and said wall portion having an inside diameter slightly greater than the diameter of the disk-shaped portion of the insulating body, the lower neck of the insulating body extending into the central opening,
• a nut engaging the external thread of the shank of the measuring electrode;
• and
• a spring part axially penetrated by the shank and interposed between the nut and the disk-shaped portion of the insulating body, whereby the cylindrical part and the insulating body are fixed by the nut screwed onto the external thread of the shank, with the tubular extension fitted in the hole of the tube wall, and the lower neck of the insulating body and the bottom portion of the cylindrical part being supported on the external surface of the tube wall.