US3230722A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Machine and method of installing plastic pipe
Assignee: Dow Chemical Co
•
Filing: 1963-01-21
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Granted: 1966-01-25
•
Expires: 1983-01-21
Abstract
No abstract record available.
Inventors
- 👤 Kenneth E Coulter
- 👤 Raymond W Maier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:43
CPC Classifications
F; F16; F16L; F16L1/00; F16L1/024; F16L1/028; F16L1/032; B; B29; B29C; B29C48/00; B29C48/25; B29C48/36; B29C48/395; E; E02; E02F; E02F5/00; E02F5/02; E02F5/10; E02F5/101; B29C48/03; B29C48/09
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
132 words
A METHOD OF FORMING A LAYING CONTINUOUS LENGTH THERMOPLASTIC PIPE UNDERGROUND IN A MANNER WHEREIN POSITIVE BACK FILL OVER SAID PIPE OCCURS THROUGH FREE FLOW OF THE EARTH COMPRISING THE STEPS OF CONTINUOUSLY DISPLACING EARTH TO FORM A CIRCULAR PASSAGEWAY UNDERGROUNG AT A DESIRED DISTANCE FROM THE GROUND SURFACE, HEATING THERMOPLASTIC TO A LIQUID CONDITION ABOVE SAID GROUND SURFACE AND THEN FEEDING SAID LIQUID THERMOPLASTIC TO SAID PASSAGEWAY, SIMULTANEOUSLY STIRRING AND APPLYING HEAT TO SAID LIQUID THERMOPLASITC ALONG THE PATH OF FLOW OF SAID THERMOPLASTIC FROM SAID SURFACE TO SAID PASSAGEWAY AND THEN EXTRUDING SAID THERMOSPLASTIC IN TUBULAR FORM THROUGH AN ANNULAR EXTRUSION SLIT FACING SAID UNDERGROUND PASSAGEWAY DIRECTLY INTO THE PASSAGEWAY AS SAID EARTH IS CONTINUOUSLY DISPLACED, AND MAINTAINING SAID TUBULAR FORM AS SAID THERMOSPLASTIC HARDENS ANS SAID EARTH BACK FILLS.
Claim 2
Independent Claim
132 words
A METHOD OF FORMING A LAYING CONTINUOUS LENGTH THERMOPLASTIC PIPE UNDERGROUND IN A MANNER WHEREIN POSITIVE BACK FILL OVER SAID PIPE OCCURS THROUGH FREE FLOW OF THE EARTH COMPRISING THE STEPS OF CONTINUOUSLY DISPLACING EARTH TO FORM A CIRCULAR PASSAGEWAY UNDERGROUNG AT A DESIRED DISTANCE FROM THE GROUND SURFACE, HEATING THERMOPLASTIC TO A LIQUID CONDITION ABOVE SAID GROUND SURFACE AND THEN FEEDING SAID LIQUID THERMOPLASTIC TO SAID PASSAGEWAY, SIMULTANEOUSLY STIRRING AND APPLYING HEAT TO SAID LIQUID THERMOPLASITC ALONG THE PATH OF FLOW OF SAID THERMOPLASTIC FROM SAID SURFACE TO SAID PASSAGEWAY AND THEN EXTRUDING SAID THERMOSPLASTIC IN TUBULAR FORM THROUGH AN ANNULAR EXTRUSION SLIT FACING SAID UNDERGROUND PASSAGEWAY DIRECTLY INTO THE PASSAGEWAY AS SAID EARTH IS CONTINUOUSLY DISPLACED, AND MAINTAINING SAID TUBULAR FORM AS SAID THERMOSPLASTIC HARDENS ANS SAID EARTH BACK FILLS.
References Cited (Backward Citations)
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US1303399A
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US1006116A
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US1340836A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-01-24 | 1969-07-26 | 1970-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-01-24 | 1973-07-26 | 1974-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-01-24 | 1977-07-26 | 1978-01-25 | $7700.00 | Window Closed / Lapsed |