The present invention relates to a temporary plug device for pipelines and more particularly to a frangible, fluid impermeable, sealing plug for use in pipeline installations. The frangible plug of the present invention is constructed and arranged to be placed at an access location in a pipeline system as it is being constructed or repaired to temporarily block fluid flow through the pipeline system. The frangible sealing plug of the invention is particularly designed for use in the construction of drain, waste and vent (DWV) plumbing systems of residential or building structures having similar plumbing systems. The frangible sealing plug is constructed and arranged for installation between pipe sections of a sewer line.
Subsequent construction completion, pressure testing of the plumbing installation may be easily performed with the frangible plug in place. When testing is complete, the frangible plug device is broken into pieces by a tool device to provide fluid flow through the pipeline. The separated pieces of the disc plug body are designed and constructed to flow out of the pipeline.
Various pipeline plug devices that temporarily block fluid flow have been proposed and used in the past, however, each such device or assembly has drawbacks and difficulties. For example, temporary plugs that are used may not be properly adapted to effectively and completely restore fill fluid flow upon removal. Incomplete removal may cause obstruction and leakage after the plug removal process. Other plug devices are more expensive, complex assemblies and which require additional time to install. The installation and removal of these and other plugs from pipelines may also be difficult and time consuming.
Another drawback of some prior art plug devices is that they may leak after time has elapsed during installation in the pipeline, thus resulting in inaccurate test results. Furthermore, some plug devices for pipelines are limited for use in specific pipelines and for specific plumbing tasks.
The frangible sealing plug of the present invention is provided to alleviate the problems and shortcomings of the prior art. The frangible plug of the present invention is a unitary structure constructed of a disc-shaped lightweight water impermeable structure, such as a plastic. The frangible disc plugs are inexpensive to manufacture, may be constructed in various sizes to fit a wide variety of pipeline diameters and provide a fixed and constant seal of the plumbing system during building construction.
An object of the present invention is to provide an inexpensive frangible disc plug device that is easily and quickly installed and effectively removable from a pipeline, such as a sewer line. The plug device is designed to be installed in a predetermined location in the sewer pipeline system as it is being constructed. For example, one embodiment is constructed and arranged to be fixed between two pipeline sections and may be accessed by means of a stub and coupling arrangement. After construction and testing of the pipeline system a removal tool is fed through the access to sever the plug body into a plurality of pieces which flow out of the plumbing system. A further benefit of this invention is that the body of the disc plug is constructed and arranged with a novel parting edge or score line arrangement to effect breakage of the plug body into a plurality of pieces to restore full and unimpeded flow of the pipeline.