Spray lance to clean tube plate of vertical steam generator drum - to insert via access opening in drum wall has radial-orifice nozzle member driven to rotate on horizontal axis

摘要

Method uses a high-pressure lance with a spray unit at its end having at least one nozzle orifice. This lance is introduced in the space and moved stepwise such that, between steps, the orifice is directed into an area between two adjoining tube rows, the sprayed liquid being collected and removed from the heat exchanger. - The unit comprises a holder fixed at the lance end and carrying at least one nozzle member which is rotatable relative to the holder about an axis parallel to the plate, connects via a duct in the holder to the lance, and has at least one radial orifice. Means are provided to rotate the member at least whilst the unit is stationary between steps.