| 摘要 |
An air bleed tube (261) is attached to a single-stage centrifugal pump (258), which has an impeller (266) and a liquid suction tube (268) whose inlet is at a center of the impeller (266). The air bleed tube (261) is attached with its air inlet at an exposed eye of the impeller (266) to bleed air from the pump (258) and thereby reduce the likelihood that the pump (258) will lose its prime. A light-touch check valve (260) at an air outlet of the air bleed tube (261) allows air at the impeller eye to be discharged from the pump (258) and at the same time prevents air from being sucked by venturi vacuum pressure in the pump (258) back into the air bleed tube (261) and the pump (258). |
