| 摘要 |
PURPOSE:To reduce the water thrust of a pump water wheel during a transition period, by arranging an auxiliary balance tube between a runner back pressure chamber and a draft pipe additionally and parallelly to a balance tube arranged for reducing the water thrust at the time when a transient phenomenon such as interception of the load of the pump water wheel or the like occurs. CONSTITUTION:A back pressure chamber 1 is connected to a lateral pressure chamber 3 through a balance tube 4, and a back pressure chamber 2 is connected to a draft pipe 9 through a balance tube 6 and further through a balance tube 5 in parallel on which a normally closed automatic valve 10 is interposed. When a transient phenomonon occurs, as the automatic valve 10 is opened and the runner back pressure chamber 2 and the draft pipe 9 are connected through by the balance tubes 6, 5, a downward water thrust during the transition period can be restrained to the normal water thrust or below. |
