| 摘要 |
PURPOSE:To stop to the minimum the elution of metal into the pure water contained in an electric machine system as well as to prevent the blocking-up of water-running path by a method wherein the pH value of the cooling water in a cooling water supplying and circulating system is controlled in the vicinity of 9. CONSTITUTION:The pH value of cooling water is detected and transmitted by a pH detecting switch 8, chemical liquid is injected into a cooling water system from a pH controlling device by opening an automatic valve 9, and said injection is continued until pH 9 is obtained. When the pH=9 is obtained, the valve 9 is closed by the signal sent from the switch 8, and the injection of medical liquid is completed. When pH>9 is going to be obtained, cooling water (pure water) 6 is circulated until the state of pH=9 is obtained. As a result, the quantity of elution (speed of corrosion) of the copper family metal contained in the cooling water system can be brought to the minimum, and the long life time of an electric machine 1 and a long period of continued operation can be expected. Besides, pure water is stored in a tank 6, it circulates and cools the electric machine 1 passing through a heat exchanger 3, a filter 4 and an ion exchanging resin tower 5 by a pump 2, and it returns the tank 6. |
