US3249665A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of lining pipe with cement
Assignee: Pan American Petroleum Corp
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Filing: 1962-11-13
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Granted: 1966-05-03
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Expires: 1982-11-13
Abstract
No abstract record available.
Inventors
- 👤 William G Bearden
- 👤 George C Howard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 05:46
CPC Classifications
B; B28; B28B; B28B19/00; B28B19/0023; G; G06; G06F; G06F7/00; G06F7/02; G11; G11C; G11C19/00; G11C19/02; G11C19/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
129 words
IN THE MANUFACTURE OF CEMENT LINED PIPE WHEREIN A CEMENT SLURRY IS DEPOSITED IN SAID PIPE, SAID PIPE IS SPUN ABOUT ITS LONGITUDINAL AXIS WHILE IN A SUBSTANTIALLY HORIZONTAL POSITION TO SPREAD CEMENT IN A SUBSTANTIALLY UNIFORM LAYER AROUND THE INTERIOR OF SAID PIPE, AND SAID CEMENT IS CURED, THE IMPROVED METHOD COMPRISING SEALING THE ENDS OF SAID PIPE, APPLYING HIGH FLUID PRESSURE TO THE INSIDE OF SAID PIPE TO EXPAND SAID PIPE DURING THE SPREADING OF SAID CEMENT, MAINTAINING SAID PRESSURE IN SAID PIPE UNTIL SAID CEMENT HAS DEVELOPED SUFFICIENT STRENGTH TO RESIST COMPRESSIVE FAILURE WHEN SAID FLUID PRESSURE IS RELIEVED AND RELIEVING THE FLUID PRESSURE IN SAID PIPE TO COMPRESSIVELY STRESS SAID CEMENT, WHEREBY THE TENDENCY FOR SAID CEMENT LINING TO SEPARATE FROM SAID PIPE IS REDUCED.
Claim 2
Dependent Claim
129 words
IN THE MANUFACTURE OF CEMENT LINED PIPE WHEREIN A CEMENT SLURRY IS DEPOSITED IN SAID PIPE, SAID PIPE IS SPUN ABOUT ITS LONGITUDINAL AXIS WHILE IN A SUBSTANTIALLY HORIZONTAL POSITION TO SPREAD CEMENT IN A SUBSTANTIALLY UNIFORM LAYER AROUND THE INTERIOR OF SAID PIPE, AND SAID CEMENT IS CURED, THE IMPROVED METHOD COMPRISING SEALING THE ENDS OF SAID PIPE, APPLYING HIGH FLUID PRESSURE TO THE INSIDE OF SAID PIPE TO EXPAND SAID PIPE DURING THE SPREADING OF SAID CEMENT, MAINTAINING SAID PRESSURE IN SAID PIPE UNTIL SAID CEMENT HAS DEVELOPED SUFFICIENT STRENGTH TO RESIST COMPRESSIVE FAILURE WHEN SAID FLUID PRESSURE IS RELIEVED AND RELIEVING THE FLUID PRESSURE IN SAID PIPE TO COMPRESSIVELY STRESS SAID CEMENT, WHEREBY THE TENDENCY FOR SAID CEMENT LINING TO SEPARATE FROM SAID PIPE IS REDUCED.
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) | 1969-05-02 | 1969-11-01 | 1970-05-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-05-02 | 1973-11-01 | 1974-05-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-05-02 | 1977-11-01 | 1978-05-03 | $7700.00 | Window Closed / Lapsed |