(1) Because lockage of ripe theory preparing and systematic system design, the ones that have been destined to no perfect.

(2) Based on the experience and lessons of lockage safety in Gezhouba Shiplock, the problem concerning lockage safety of multi-step ship lock were analyzed and approached.

(3) The lift will practically prevent all loss of water by lockage under the present system.

(4) However, the auxiliary lock is not equipped with tow haulage equipment, so double lockage tows require special pull boat assistance.

(5) The utility model relates to a flow meter of novel, particularly for the measuring occasion of the lockage flow quantity of open canal.

(6) The utility model can automatically discriminate the four flow regimes of the lockage water flow, and select corresponding formula to calculate the flow quantity.

(7) The relationship between the tonnage and area of inland vessels is needed to calculate the average lockage tonnage reasonably.