Method and apparatus for removal of utility line and replacement with polyolefin pipe
AssigneeTTI Trenchless Technologies, Inc.
InventorsRobert O. Parish, II, Cleve C. Reber
Life of this patent
Estimating the term…
Abstract
The present invention is directed to a method for removing a utility pipe or main and replacing the main with a polyolefin pipe. More specifically, the unique apparatus or system of the present invention includes a rotating head connected to a plurality of pipe joints to remove the old pipe, usually concrete or tile, by cutting, chipping and grinding. The head has an outer periphery of roller bits which cut, chip and grind the old pipe or earth into pieces which pass inwardly through the head. Behind the head is a non-rotating member which opens and packs the hole formed by the head for the replacement polyolefin pipe which is pulled into the hole by the member.
Claims9
A method for removing an existing utility main and replacing said main with a polyolefin pipe which comprises:
- exposing two ends of a section of said main;
- attaching to a drilling unit a drill string of pipe joints:
- extending said drill string inside said main, from one exposed end of the section of the main to the other exposed end of the section of the main;
- imparting linear pulling motion and rotation from said drilling unit to said drill string;
- rotating inside said main a plurality of roller bits supported by a head attached to said drill string, said roller bits engaging, scoring, cutting, and chipping said main into pieces, said pieces then passing through said head, leaving an empty hole;
- packing said pieces into said hole.
A system for entering and removing an existing utility main and replacing said main with a polyolefin pipe comprising:
- a drill string of pipe joints:
- a head connected to said drill string;
- a plurality of roller bits mounted on said head;
- a swivel;
- attached to said head
- a pipe-pulling attachment member attached to said swivel;
- a polyolefin pipe attached to said pipe-pulling attachment member:
- and
- means to rotate said drill string and head and to provide linear pulling movement to the drill string, the head, the swivel, the pipe-pulling attachment member, and the polyolefin pipe.
Dependencies are inferred from the claim text.