The use of polyolefin pipe in the utility industry has become commonplace. The current accepted pipe is polyethylene pipe. Currently there are two basic methods used to repair existing lines such as broken sewer lines made of concrete or tile with polyethylene pipe. One is called slip lining which is pulling a smaller polyethylene pipe through an existing pipe. The other is a method which breaks the existing pipe and at the same time pulls in a polyethylene pipe. This latter method can maintain the pipe diameter at the same internal diameter with the replacing polyethylene pipe as was present in the broken pipe. These methods are being used by cities and municipalities to fix the infrastructure of their waste water systems. These projects are carried out on the city or municipality easements. However, both methods now require that the service connection, i.e. the connections from a house or business (the line or pipe on private property) be carried out usually in a pit which is 5 feet (5') to 12 feet (12') deep. Often these pits are in the backyards of person's homes and to allow sufficient room for a man to enter the pit, as many as 5 to 8 yards of dirt must be removed and stored. The available connectors for connecting the service connection or line to the new polyethylene pipe are saddles which are held onto the new polyethylene pipe by clamps. The clamps are very similar to the clamps used on hoses in a car but having much greater diameters since the lines are 8" to 12" in diameter. To the saddle connectors clamped to the new polyethylene pipe are a variety of polyvinylchloride (PVC) pieces which are connected to the service or private line to complete the service connection.
The problems with the current methods of making the service connections are many. They include the need to excavate large amounts of dirt to get to the site of the connection, disposal of the large amount of dirt removed and the pit needs to be shored to meet OSHA standards for working at levels greater than 5 feet deep. The use of saddles and clamps requires that access be obtained completely around the new polyethylene pipe and clamps cannot completely seal the saddle to prevent infusion of water which is passing on the outside of the polyethylene pipe, the intrusion of roots and the chance that the saddle is moved or disturbed during refilling the pit. Any one of these problems can make the connection a major and costly problem; collectively, these are each overcome by the apparatus and method of the present invention.
U.S. Pat. No. 4,647,073 discloses a clamping device for connecting a branch pipe to a main pipe buried underground. The clamp is lowered to the main pipe from the surface.
U.S. Pat. No. 4,832,069 discloses a method for tapping water mains by minimal excavation to expose the upper half of the main and then locating (with respect to the main) a conventional pipe tapping device but without employing means encircling the pipe.
U.S. Pat. No. 4,978,255 discloses a method for tapping a ferrous pipe through a saddle adhered to the surface of the pipe by an adhesive, the saddle having a closure member which prevents the adhesive entering the bore.
The patents are all related to methods used either with water or gas utility lines.
USPTO Backgrounds
USPTO Backgrounds