Patent ID: 7635006

Claim:
A method for sealing of a pipe ( 4 ) that is inaccessible from the outside due to its location inside building elements or, that is in the ground, and in which a fluid coating material is sprayed out of at least one nozzle ( 2 ) moved through the pipe to be sealed, towards the inner wall ( 3 ) of the pipe for covering at least parts of the inner wall of the pipe thereof, and in which the coating material then hardens for forming a part of the wall of the pipe where it has been applied, and wherein the method is for sealing of pipes having one or more substantial holes ( 12 ) though the pipe wall, the method comprising: introducing into the pipe to be sealed, prior to said spraying, at least one unperforated material piece ( 10 ) that is divided in the longitudinal direction thereof and held together by means ( 11 ) for holding the unperforated material piece ( 10 ) together to a form pipe piece ( 17 , 17 ′) with a smaller outer diameter than the inner diameter of the pipe, to a location of a substantial hole through the pipe wall for covering the hole; after introducing the pipe piece ( 17 , 17 ′) into the pipe, to the location of the substantial hole through the pipe, then braking the means for holding the unperforated material piece together so that the pipe piece increases in diameter while releasing potential energy in the unperforated material piece to bear in direct contact against the inner wall of the pipe without coating material between the pipe piece and the pipe so that the unperforated material piece forming the pipe piece has no ability to seal said hole alone, but it forms in the subsequent spraying of the coating material an auxiliary wall in the same pipe as that in which the nozzle is located over the hole for retaining the material sprayed within the pipe, said material piece being introduced into the same pipe as that in which the nozzle is located, and said sprayed coating material being retained within the pipe in which the material piece is located; and after braking the means for holding the unperforated material piece together, using the nozzle ( 2 ) to spray the fluid coating material onto an inner surface of the pipe piece ( 17 , 17 ′) and onto the inner wall ( 3 ) of the pipe ( 4 ) adjacent the pipe piece not covered by the pipe piece, to form a coating material layer ( 8 ) on the inner surface of the pipe piece ( 17 , 17 ′) and the adjacent inner wall for sealing the auxiliary wall and the substantial hole ( 12 ) at said location.