US4020641A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of laying pipes in the ground
Assignee: Komatsu Ltd
•
Filing: 1975-12-22
•
Granted: 1977-05-03
•
Expires: 1995-12-22
Abstract
Abstract There is disclosed a method of laying small-diameter pipes such as gas, water pipes or the like precisely in position in the ground. Small-diameter pilot pipes are first laid in with a pilot head being measured and controlled in order to make its advance straight. Pipes which are larger in diameter than the pilot pipes are then laid in successively, the large-diameter pipes being led by the pilot pipes. A multistage head is used as a head utilized for consolidation of soil and disposed in a following relationship to the pilot pipes, thereby reducing resistance exerted upon the head.
Inventors
- 👤 Hiroshi Takada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 03:15
CPC Classifications
E; E21; E21B; E21B7/00; E21B7/20; E21B7/201; E21B7/203; E21B7/04; E21B7/046; E21B7/06; E21B7/068; E21B7/28
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
253 words
A method of laying pipes in the ground comprising: a. digging a departure pit and an arrival pit spaced apart from the departure pit; b. providing a propulsion jack in said departure pit, the propulsion jack being adapted to press and propel pipes to be laid in; c. pressing a pilot head into the ground in said departure pit in a direction towards said arrival pit by means of a pilot jack coupled thereto and then pressing said pilot head further into said ground, wherein the pilot jack is placed into a contracted state by the pressing force of said propulsion jack; d. pressing pilot pipes successively into the ground by said propulsion jack, said pilot pipes being in a following relationship with said pilot head; e. measuring the position and posture of said pilot head at the departure pit during the pressing and laying-in of the pilot head; f. controlling the straight advance of the pilot head based on said measurement; g. bringing a multistage head into abutment against the rearmost end of the laid-in pilot pipes after the latter are laid in; h. pressing the rear end of said multistage head and laying in the multistage head by said propulsion jack; i. connecting pipes to be laid in to the rear end of said multistage head, said pipes being larger in diameter than said laid-in pilot pipes; j. propelling said pipes in succession into the ground by said propulsion jack; and k. collecting said laid-in pilot pipes in the arrival pit.
Claim 2
Independent Claim
253 words
A method of laying pipes in the ground comprising: a. digging a departure pit and an arrival pit spaced apart from the departure pit; b. providing a propulsion jack in said departure pit, the propulsion jack being adapted to press and propel pipes to be laid in; c. pressing a pilot head into the ground in said departure pit in a direction towards said arrival pit by means of a pilot jack coupled thereto and then pressing said pilot head further into said ground, wherein the pilot jack is placed into a contracted state by the pressing force of said propulsion jack; d. pressing pilot pipes successively into the ground by said propulsion jack, said pilot pipes being in a following relationship with said pilot head; e. measuring the position and posture of said pilot head at the departure pit during the pressing and laying-in of the pilot head; f. controlling the straight advance of the pilot head based on said measurement; g. bringing a multistage head into abutment against the rearmost end of the laid-in pilot pipes after the latter are laid in; h. pressing the rear end of said multistage head and laying in the multistage head by said propulsion jack; i. connecting pipes to be laid in to the rear end of said multistage head, said pipes being larger in diameter than said laid-in pilot pipes; j. propelling said pipes in succession into the ground by said propulsion jack; and k. collecting said laid-in pilot pipes in the arrival pit.
Claim 3
Dependent Claim
16 words
A method according to claim 1, further comprising collecting said multistage head in the arrival pit.
Claim 4
Dependent Claim
43 words
A method according to claim 1, further comprising withdrawing said pilot head and said laid-in pilot pipes toward the departure pit, and laying in the pipes again with the straight advance of the pilot head being measured and controlled at the departure pit.
Claim 5
Dependent Claim
40 words
A method according to claim 1, further comprising propelling first a foremost head of said multistage head by hydraulic means provided independent of the propulsion jack, and propelling finally a rearmost head of said multistage head by said propulsion jack.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-05-02 | 1980-11-01 | 1981-05-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-02 | 1984-11-01 | 1985-05-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-02 | 1988-11-01 | 1989-05-03 | $7700.00 | Window Closed / Lapsed |