A system for cleaning tube-type heat exchangers automatically during operation

A tube assembly through which a fluid is to flow and containing a device for cleaning the tube and/or preventing the accumulation of deposits therein, the device consisting of a helix 2 of a material which is resistant to corrosion and abrasion, which can be constantly agitated and thus repeatedly brought into contact with the internal walls of the tube 1 under the effect of the fluid stream, the helix 2 being held in position against longitudinal movement by a hook 4 disposed at the upstream end of the helix 2 which hook permits rotation of the helix 2 within the tube 1. <IMAGE>