US 4,507,019 A · Method and apparatus for replacing buried pipe

Abstract

A pipeline replacement system incorporating an expansion and line replacement mandrel and having a power system for imparting linear movement and rotation to the mandrel. Within the scope of the invention, the mandrel may be pushed or pulled or both pushed and pulled through an existing buried pipeline by the power system while being rotated by the power system. The mechanism, in a single pass, breaks up the existing pipeline, forces the broken fragments of the pipeline into the surrounding earth and positions a replacement pipe of the same dimension or larger dimension in place of the existing pipeline. A swivel system allows the replacement pipe to be moved linearly into the expanded passage behind the mandrel without rotation. The power system includes a mechanism or mechanisms for applying pushing, rotational and pulling forces to the mandrel.

Claims19

Dependent claims

A method of replacing buried nonmetal tile pipe with replacement pipe having an internal diameter that may exceed the internal diameter of the existing buried tile pipe comprising:

(a) locating pipe fracturing and replacement apparatus in axial registry with the centerline of the pipe to be replaced, said pipe fracturing and replacement apparatus having a pipe fracturing mandrel of generally frusto-conical configuration and having a diameter at its leading extremity not greater than the internal diameter of said buried nonmetal tile pipe and a diameter at its trailing extremity which is greater than the outer diameter of said replacement pipe;
(b) simultaneously forcing said pipe fracturing mandrel through said buried tile pipe, reducing the pipe to be replaced to a fractured form having a multitude of pipe fragments of irregular form and
forcing each of the pipe fragments of the fractured tile pipe radially outwardly into the surrounding earth formation thus forming a replacement pipe passage of a dimension exceeding the external dimension of the replacement pipe;
and
(c) extending a replacement pipe into the passage simultaneously with passage of said pipe fracturing mandrel through said buried nonmetal tile pipe.

2 more elements

Apparatus for fracturing and expanding buried fracturable tile pipe and positioning a replacement pipe with its centerline substantially coincident with said buried fracturable tile pipe, comprising:

(a) an elongated pipe fracturing and displacement mandrel having a generally frusto-conical pipe fracturing and expanding portion having a small extremity not greater than the internal diameter of said buried fracturable tile pipe and a large extremity exceeding the external dimension of said replacement pipe, said pipe fracturing and expanding portion, upon being forced through said buried fracturable tile pipe, reducing said buried fracturable title pipe to a multitude of pipe fragments of irregular form and forcing said pipe fragments radially outwardly into the soil within which said fracturable tile pipe is buried;
(b) means for moving said pipe fraacturing and displacement mandrel through said buried fracturable tile pipe;
(c) connector means mounted on said mandrel at the trailing portion of said pipe fracturing and expanding portion, said connector means adapted for connection to the leading end of said replacement pipe whereby said replacement pipe is moved linearly into the passage occupied by said buried fracturable tile pipe before fracturing and expansion thereof.

Dependencies are inferred from the claim text.

Method and apparatus for replacing buried pipe

Life of this patent

Method and apparatus for replacing buried pipe

Life of this patent

Abstract

Claims19