Title:
【発明の名称】管裂開および取替装置と方法
Document Type and Number:
Japanese Patent JPH05506293
Kind Code:
A
Abstract:
Tool for slitting and laterally expanding underground steel gas mains and inserting replacement plastic piping into the spread apart pipeline has a forward end cylindrical portion mounting a single, rearwardly angled blade to make only one line of cut, and a conical pipe spreader portion at its rearward end. The conical spreader portion is eccentrically disposed with respect to the forward end cylindrical portion. A single roller type pipe slitter aligned with the fixed blade may be mounted on a removable extension of the forward end cylindrical portion, to initially groove and weaken the pipe along the intended line of cut. A pneumatically operated impact ram is attached to the rearward end of the tool, as is the leading end of the replacement piping. A wire cable pulls the tool through the underground pipe, thereby grooving, slitting and laterally expanding the pipe. The spacing of the roller slitter in advance of the fixed knife blade is dimensionally related to the length of any coupling or clamp as may be anticipated along the line of cut, and the spacing distance of the fixed knife blade forwardly of the conical spreader portion is related to the cone angle of the latter to increase hoop tension immediately in front of the fixed blade as the cutting proceeds.
Inventors:
Fisk, Alan Thi
Fried, David Eye
Man, Thomas A.
Fried, David Eye
Man, Thomas A.
Application Number:
JP50556491A
Publication Date:
September 16, 1993
Filing Date:
February 13, 1991
Export Citation:
Assignee:
Consolidated Edison Company of New York, Inc.
International Classes:
B23D21/02; F16L55/18; E21B7/20; E21B7/30; E21B29/00; E21D9/06; F16L1/024; F16L55/165; (IPC1-7): F16L55/18
Attorney, Agent or Firm:
Soga Doteru (6 people outside)