PURPOSE: To provide the novel titled process capable of enhancing the covering effect to seek prevention of leakage over a long period, by multilayer formation of covering layers on the inner surface of a pipe throughout its length using different sorts of sealers corresponding to each layer.
CONSTITUTION: A truck 2 provided with a ring 3 pressing the inner surface of e.g. a gas pipe 1 and carrying a spray-gun 4 located at the axis of the pipe 1, is inserted, through a pit P, in the pipe 1 of a relatively large diameter laid underground. Next, while making the truck 2 travel from a pit P to the adjacent pit P, a compressor 6 is operated to charge a sealer S1 stored in a tank 5 via a connecting pipe 7 to the spray-gun 4, through which said sealer S1 is ejected, resulting in entire covering of the inner surface of the pipe throughout its length. After solidfying the sealer S1, another sealer S2, charged in the tank 5 in place of the sealer S1, is subjected to covering process in the same way as the above, while making the truck 2 travel in the opposite direction to the process described above. The covering process men tioned above is repeated desired times.
OOTANI TOORU
SAKAI TAKASHI
| JPS51145545A | 1976-12-14 |