Process of making safe old lead-made pipes of water distribution system with no need to dig, by introducing expandable plastic tube with expandable introduction head, and sealing-off internal walls of lead pipe under pressure

摘要

Use of expandable polyethylene terephthalate tube which is introduced inside old lead tubing up to the tap point of main canalization system, heated with heat-carrier fluid and finally expanded under pressure to seal off internal walls of lead pipe, thus making it safe. The process of making safe the old lead tubing (1) comprises introduction (after closing the tubing supply tap) of expandable tube (4), up to the tap, starting from the consumer end of piping, followed by heating with heat-carrier fluid and finally internal lining of old pipe (1) by expanding tube (4) by means of increased pressure of fluid contained within it. An Independent claim is also included for the equipment for conducting the process as claimed, comprising expandable guiding head (5) situated at the end of tube (4) made of polyethylene terephthalate, of length corresponding to that of pipe to be made safe, and linked to source of hot water allowing to bring temperature to minimum 85 deg C and pressure to minimum 1.5 bar and additional tube introduced into tube (4) and ensuring continuous circulation of water.