Unclogging and recovering device for sludge deposited on the tube plate of a steam generator

Claim 1

Device for unclogging and recovering sludge deposited on the tube plate of a steam generator comprising, in a cylindrical vessel with a vertical axis, a vertical bundle of tubes bent into a U connected at each of their lower ends to a horizontal tube plate fast to the vessel of said steam generator and supported at its central part by a vertical hollow column fast to the lower end of said steam generator, a high temperature fluid being brought to the tubes of said bundle beneath said tube plate, to provide the heat enabling vaporization of the feedwater introduced into the upper part of said steam generator in contact with the tubes of said bundle, this feed water causing the deposit of sludge on said tube plate, said device comprising: (a) a ramp for unclogging by high pressure jets fixed permanently to the inside of said steam generator horizontally and above said tube plate, in a direction diametric to the latter, supplied with water under pressure through a distributor movable inside said ramp in the longitudinal direction of the latter, for the constitution of high pressure jets directed towards said tube plate, at different places according to the length of said ramp; (b) means for driving towards the center of said tube plate sludge which is formed during operation and which is stirred up by said water jets; and (c) a discharge valve for the sludge arranged above an orifice passing through said tube plate at its central part and opening into said hollow central column.