05192165 is referenced by 27 patents and cites 14 patents.

A method and apparatus for replacing an individual conduit located within a bank of individual conduits, without rendering inoperable the surrounding adjacent individual conduits of the bank. A conduit expander is pulled through the subject individual conduit to break it and push the pieces out. Knife blades may be used to split the individual conduit. A rearward flared out portion pushes the broken conduit outwardly far enough for a new conduit to be moved therethrough, but not far enough to render inoperable the surrounding adjacent individual conduits of the bank. A replacement conduit is attached to the rear end of the conduit expander and moved into the individual conduit as the conduit expander moves therethrough.

Title
Trenchless replacement of conduits in an underground conduit bank
Application Number
7/864358
Publication Number
5192165
Application Date
April 6, 1992
Publication Date
March 9, 1993
Inventor
Robert J Torielli
Piscataway
NJ, US
Agent
Larson and Taylor
Assignee
PIM Corporation
NJ, US
IPC
F16L 55/18
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