| 摘要 |
<p>PROBLEM TO BE SOLVED: To uniformly and easily clean a coolant flow passage provided with plural branched parts by providing a cleaning unit for cleaning the coolant flow passage while circulating a cleaning medium, closing at least one of the branched parts at the time of circulating the cleaning medium and circulating the cleaning medium while switching the branched part to be closed. SOLUTION: The cleaning unit 10 is provided for cleaning existing coolant pipe lines 2A, 2B by utilizing a secondary coolant system. The coolant flow passage is constituted of the existing pipe lines 2A and 2B and a joint pipe lines 30. The inside of the coolant flow passage is cleaned by closing at least one of plural branched parts 11 of the coolant flow passage and cleaning while circulating the cleaning medium in the coolant flow passage. Next, the opening/ closing state of the branched parts 11 of the coolant flow passage is switched to close at least one of plural branched parts 11 and the coolant flow passage is cleaned. The cleaning medium is repeatingly circulated while switching the branched parts 11, through which the cleaning medium is passed, in this way. As a result, the coolant flow passage is uniformly and simply cleaned.</p> |
