05076731 is referenced by 32 patents and cites 9 patents.

The apparatus comprises a mole to be pulled through an existing pipe provided with a cone-shaped head portion for widening an existing pipe, a cutting arrangement with radially protruding blades in front of the effective head portion and a guidance portion having a cylindrical portion centered on the mole axis which precedes the cutting arrangement, the diameter of the cylindrical part being slightly smaller than the bore diameter of the existing pipe. For cutting along two lines parallel to the line of apparatus advance and for centering the apparatus in the existing pipe in the case of any usual utility line, a cable passes axially through the cylindrical portion of the apparatus and is fastened to the head portion of the mole. The guidance portion is loosely attached to the cone-shaped head portion and is axially moved through the existing pipe by the head portion and the cable.

Title
Apparatus for bursting an existing pipe and widening the bore thereof
Application Number
7/501145
Publication Number
5076731
Application Date
March 29, 1990
Publication Date
December 31, 1991
Inventor
Edmund Luksch
Heusenstamm
DE
Agent
Blakely Sokoloff Taylor & Zafman
Assignee
Diga Die Gasheizung
DE
IPC
F16L 54/18
F16L 1/00
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