| 摘要 |
<p>An injection plug for fitting into a hole in a wall has a head and a semirigid cylindrical shaft with outer serrations or slightly larger external dia. than the internal dia. of the hole. The head contains a seating for receiving an injection or grouting nozzle and passages communicating with the internal space of the shaft and with passages in the nozzles. The former passages house resilient, self-closing, non-return valves, which prevent injected liq. from flowing back out of the hole. These valves are pref. conical, with the slit-shaped outlets at their apexes, and are pref. of rubber. The injection plug itself is pref. of very dense polyethylene. Esp. useful as a plug for injection or grout hols in the soffit or wall of tunnel or mine, partic. where a two-component thermosetting epoxy or other resin is used. The plug acts both as the connector for the grout pipe and, after the grout pipe has been removed, as a permanent seal.</p> |
