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US5097871A Expired / Lapsed US ⏱️ 0.0 years remaining

Pipe for pipe jacking

Assignee: Kurimoto Ltd
•
Filing: 1991-01-24
•
Granted: 1992-03-24
•
Expires: 2011-01-24
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Abstract

Abstract In pipe jacking wherein a pipe line is formed by horizontally inserting pipes one by one from a vertical pit without moling the ground, a pipe of spigot and socket type to be used is coated with such material as concrete to form an uniform common external diameter from a flange section with its external diameter enlarged to a spigot section, a pipe whose external surface is covered with another smooth outer pipe so as to make the external surface smooth and reduce frictional resistance is provided.

Inventors

  • 👤 Masahiro Ohta

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 23:22
CPC Classifications
E; E21; E21B; E21B17/00; E21B17/02; E21B17/08; F; F16; F16L; F16L21/00; F16L21/02; F16L21/03

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 103 words
A pipe for use in pipe jacking, comprising: a pipe body having a socket at one end and a spigot extending along its other end thereof; an annular flange mounted to said spigot, said annular flange having an outer pipe engaging surface; an outer pipe having a smooth external surface fixed to and extending between the outer pipe engaging surface of said flange and the outer surface of said socket, said outer pipe, flange, spigot and socket defining an annular gap filled with a filler; and a reinforcing rib situated in said annular gap and engaging said flange, said spigot and said filler.
Claim 2
Dependent Claim 103 words
A pipe for use in pipe jacking, comprising: a pipe body having a socket at one end and a spigot extending along its other end thereof; an annular flange mounted to said spigot, said annular flange having an outer pipe engaging surface; an outer pipe having a smooth external surface fixed to and extending between the outer pipe engaging surface of said flange and the outer surface of said socket, said outer pipe, flange, spigot and socket defining an annular gap filled with a filler; and a reinforcing rib situated in said annular gap and engaging said flange, said spigot and said filler.
Claim 3
Dependent Claim 13 words
The pipe as defined in claim 1, wherein the pipe body as iron.
Claim 4
Dependent Claim 12 words
The pipe as defined in claim 1, wherein the filler is sand.
Claim 5
Dependent Claim 13 words
The pipe as defined in claim 1, wherein the filler is foaming mortar.

References Cited (Backward Citations)

GB189704051A Cited
US3279003A Cited
US3516447A Cited
US3864908A Cited
US4345625A Cited
US4114657A Cited
US4240470A Cited
US4361336A Cited
US4432396A Cited
US4778202A Cited
JPS6312697A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-03-24 1995-09-23 1996-03-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-03-24 1999-09-23 2000-03-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-03-24 2003-09-23 2004-03-24 $7700.00 Window Closed / Lapsed

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