Method and apparatus for replacing buried pipe

Claim 3

A method as recited in claim 1, wherein: said method steps of paragraphs (b) and (c) are accomplished in a single pass with said pipe fracturing and replacement apparatus.

Claim 4

A method as recited in claim 1, wherein: said pipe fracturing mandrel is forcibly moved through the buried nonmetal tile pipe by simultaneous linear and rotatational components of movement.

Claim 5

A method as recited in claim 1, wherein: said pipe fracturing mandrel is moved through said pipe by a pushing force.

Claim 6

A method as recited in claim 1, wherein: said pipe fracturing mandrel is moved through said pipe by a pulling force.

Claim 7

A method as recited in claim 1, wherein: said pipe fracturing mandrel is moved through said pipe by both pushing and pulling forces.

Claim 8

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.

Claim 9

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.

Claim 10

Apparatus as recited in claim 7, wherein: said means for moving said pipe fracturing and displacement mandrel through said buried fracturable tile pipe comprises means for applying a pushing force to said pipe fracturing and displacement mandrel.

Claim 11

Apparatus as recited in claim 7, wherein: said means for moving said pipe fracturing and displacement mandrel through said buried fracturable tile pipe comprises means for applying a pulling force to said mandrel.

Claim 12

Apparatus as recited in claim 7, wherein: said means for moving said pipe fracturing and diplacement mandrel through said buried fracturable tile pipe comprises means for applying simultaneous pushing and pulling forces to said pipe fracturing and displacement mandrel.

Claim 13

Apparatus as recited in claim 7, wherein: said means for moving said pipe fracturing and displacement mandrel through said pipe induces simultaneous linear and rotary movement to said pipe fracturing and displacement mandrel.

Claim 14

Apparatus as recited in claim 1, wherein: a plurality of hard boring projections are embedded within said pipe fracturing and expanding portion, said hard projections extending radially outwardly from said pipe fracturing and expanding portion for scoring engagement with the internal surface of said buried fracturable tile pipe.

Claim 15

Apparatus as recited in claim 7 wherein said means for moving said mandrel through said pipe comprises: (a) elongated support track means adapted for location in substantially parallel relation with the grade of said buried fracturable tile pipe, said track means defining spaced abutment means; (b) jacking means being suported by said track means and having force transmitting relation with said abutment means; and (c) elongated rigid force transmitting means interconnecting said jacking means and said pipe fracturing and displacement mandrel.

Claim 16

Apparatus as recited in claim 13, wherein said jacking machine comprises: (a) a power system driven by engine means, said power system imparting rotary movement to said rigid force transmitting means and said pipe fracturing and displacement mandrel; (b) block means having abutment engagement means; and (c) linear hydraulic motor means interconnecting said power system and said block means and, when energized, imparting linear movement to said power system relative to said track means and thus imparting linear movement to said rigid force transmitting means and said pipe fracturing and displacement mandrel.

Claim 17

Apparatus as recited in claim 14, wherein: said linear hydraulic motor means imparts a pushing movement to said block means to move said power system relative to said track means.

Claim 18

Apparatus as recited in claim 14, wherein: said hydraulic motor means imparts a pulling movement to said block means to move said power system relative to said track means.

Claim 19

Apparatus as recited in claim 13, wherein: said elongated rigid force transmitting means is defined by elongated pushing bar means adapted to extend through said replacement pipe and being releasably connected to said pipe fracturing and displacement mandrel.

Claim 22

Apparatus as recited in claim 13, wherein: said elongated rigid force transmitting means comprises: (a) sections of elongated pusher bar being connectable end-to-end being capable of transmitting predetermined pushing force to said pipe fracturing and replacement apparatus; and (b) said jacking means facilitating incremental pushing movement of said sections of elongated pusher bar and connection of additional sections of elongated pusher bar and replacement pipe for replacement of a desired length of buried fracturable tile pipe.