| 摘要 |
A multi-wire conduit dam for constructing seals in electrical conduits to prevent migration of flammable and explosive gases and liquids to potential ignition sources. This invention is designed to provide a practical, convenient and economical alternative to conventional methods of sealing off electrical conduits from flammable and explosive gases and liquids, including particularly the conventional methods of providing a dam by stuffing a fibrous insulation material around the wire bundle and between the wires. The device of the present invention consists of a cylindrical dam of resilient material cut or molded to snugly fit the interior diameter of a vertical electrical conduit seal-off fitting, the cylindrical dam having a wire orifice for each wire which is aligned with the axis of the dam and which has a diameter providing for a tight fit around the wire. The wire orifices may be molded or punched in the dam or may be formed by a heated probe inserted through the dam at the desired positions. The wire orifices are located to provide for the desired or required clearance between the wires. Two dams are used for horizontal seal-off fittings. Each wire is passed through a respective wire orifice and the dam or dams are slid along the wires into a conduit seal-off fitting. A time-curing sealant compound is then poured through the seal-off fitting access port on top of the dam, for vertical fittings, or between the dams, for horizontal fittings, where it is allowed to cure. The seal prevents flammable or explosive gases and liquids from traveling through the electrical conduit to an ignition source consistent with code requirements. |
