Drive apparatus for installing flexible pipe through in-situ pipe

Abstract

Pusher apparatus and a method of using the apparatus inserts a flexible liner into an in-situ pipe. At least a pair of contra-rotating resilient drive assemblies, having a nip therebetween, drive the liner into the pipe. A guide tube can extend between the drive assemblies and the pipe. A pull head can be affixed to a leading end of the liner and adapted for sealing within a bore of the pipe and pressured fluid can be applied to pull a leading end of the liner into the pipe while the pusher pushes. The contra-rotating resilient drive assemblies can be one or more pair of opposing wheels or opposing tracks. Track assemblies can be mounted to a frame which is movable on rails and restrained with a load cell for measuring reactive forces while pushing. The rails can be angled for aligning the nip with the pipe.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application is a regular application claiming priority of U.S. Povisional Patent Application Ser. No. 60 / 989,912 filed on Nov. 23, 2007, the entirety of which is incorporated herein by reference for all purposes.FIELD OF THE INVENTION[0002]The present invention relates to apparatus and methods for remediation of in-situ existing pipelines and more particularly to inserting a flexible pipe such as plastic and fiberglass-reinforced composite liner into an existing conduit or pipeline and more particularly to driving assemblies for pushing pipe into the in-situ pipe using opposing wheels, opposing tracks, and optional pull assemblies for hydraulically assisting of said drive assemblies.BACKGROUND OF THE INVENTION[0003]Pipelines which carry fluids are susceptible to deterioration, corrosion and other conditions which seriously affect the lifespan of the pipe. Excavation of a pipeline or pipe, to replace sections that have deteriorated, is...

AI Technical Summary

Benefits of technology

[0019]In other embodiments, the tracked drive can be similarly fit with a pull

Problems solved by technology

Pipelines which carry fluids are susceptible to deterioration, corrosion and other conditions which seriously affect the lifespan of the pipe.

Excavation of a pipeline or pipe, to replace sections that have deteriorated, is costly and often detrimental to the environment.

In-situ pipelines of pipe typically build corrosion and scale on an inner surface, over time.

Large pipes can be cleared using pigging techniques, however smaller diameter pipes do not lend themselves to this type of cleaning technique.

Due to the unwieldy lengths of liner that are required, the supply of liner is provided at surface and must be fed into the excavation down into the bore of the pipe.

Due to the angle of the minimal excavation and the usual horizontal plane of the in-situ pipe, the orientation and insertion of inflexible liners presents a challenge.

Particularly when a large axial force is required to advance the liner, difficulties in handling are increased due to the flexibility of this type of liner—it is difficult to push a rope.

Further, the composite nature of the liner does not permit overly rough handling.

While suited for many applications and installation of composite pipe, the maximum driving force is limited and the wheeled drive interface can impose high loads on the liner.

Images