| 摘要 |
1287891 Sealing leaks in pipes SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ NV 5 Nov 1969 [18 Dec 1968] 60225/68 Heading F2P Pipe leaks are sealed by depositing petroleum wax at the leakage point from a liquid wax dispersion, emulsion or solution or from a dispersion of wax in a gaseous dispersion medium. The wax may be a paraffin wax. The waxcontaining blend may include water, petroleum lubricating oil, kerosine or a liquefied gas, e.g. propane. Wax additives, e.g. ethylene/vinyl acetate copolymer or ethylene/propylene copolymer, or a cationic emulsifier may be included in the blend. The wax blend may be introduced under pressure into and retained in the pipe for a suitable time and then drained to effect the seal. Alternatively, the blend may be such as to convert into an aerosol on entering the pipe. Packed spigot and socket joints may be sealed. |
