The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 29, 1986
Filed:
Dec. 24, 1984
Tokyo Gas Co., Ltd., Tokyo, JP;
Hakko Co., Ltd., Tokyo, JP;
Abstract
A system for repairing joints in pipes laid underground, such as gas pipes, in their buried state, from their inside, to ensure their sealing. The system, in the process of pushing the resin used for repairing along the inside of the pipes by the pig, is to fill and seal the sealing material with the resin through gaps in numerous pipe joints inside of the pipes. In order to guarantee insertion of resin into gaps in the pipe joints (sealing material) whether or not the pipe joint has developed a leak, the system comprises a substitution pig, and a means whereby the pig pushes the resin placed ahead of it along the pipe, and further, a means whereby the filling amount of the resin does not change even if the amount of resin present in front of the pig differs between the early and later stages of the repairing operation, gaps in the pipe joints will be uniformly filled.