AIR SUCTION AND SUPPLY STOPPER

摘要

PURPOSE:To interrupt an electric power source for electrolysis while the flow rate of sea water is small or the sea water does not flow at all by providing a flowmeter to a bypass pipeline for the sea water with a tank type device for supplying electrolytic iron ion in order to form a ferrous corrosion preventive film on the inside surface of a copper alloy tube of a heat exchanger utilizing the sea water. CONSTITUTION:Sea water is partly passed through a bypass pipe 4 to an electrolytic cell 9 and is electrolyzed by electrodes 10 to generate Fe ion on anodes in the stage of passing the sea water as a heat transmission medium from a cooling water pipe 2 to a copper alloy tube of a heat exchanger 1. An Fe corrosion preventive film is formed on the inside surface of the copper alloy tube by the Fe ion. There is the danger that the cell 9 is damaged or the gaseous H2 formed as a result of the electrolytic reaction stagnates in the upper part of the cell 9 when the amt. of the sea water flowing to the pipe 4 decreases sharply or the flow thereof stops. A sea water flowmeter 13 is provided in the pipeline 4 and a DC power source 11 for electrolysis is automatically interrupted upon decreasing of the flow rate of the sea water passing through said meter to stop the conduction of the current to the electrodes 10 in order to prevent the above-mentioned danger.