Stoplogs are used for initial blocking of inlet channels for water extractions. This means they facilitate inspection and maintenance of downstream coarse and fine bar screens.
Guide frames are fitted on the channel floor and the channel walls in the first concrete of the channel walls to guide the stoplogs. This is sealed using an all-round neoprene seal. The stoplogs are raised and lowered using a lifting beam, which feeds the stoplogs precisely in the guide frame with the aid of a crane. Depending on the length of guide frame available, the stoplog can be parked in the upper section of the guide shaft if it is not needed for blocking purposes.