Patent US3943996A successfully refreshed from Google Patents.
US3943996A
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Low fluid loss cementing compositions
Assignee: Calgon Corp
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Filing: 1975-06-27
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Granted: 1976-03-16
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Expires: 1995-06-27
Abstract
Abstract Improved cementing compositions and their use in well cementing operations is disclosed, wherein methacrylamidopropyltrimethylammonium chloride polymers are used as fluid loss additives for aqueous hydraulic cement slurries.
Inventors
- 👤 Lawrence James Guilbault
- 👤 Frederick Alan Hoffstadt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 19:07
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/42; C09K8/46; C04; C04B; C04B24/00; C04B24/24; C04B24/26; C04B24/2652
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
90 words
A method of cementing a zone in a well penetrating a subterranean formation comprising injecting down the well and positioning in the zone to be cemented an hydraulic cement aqueous slurry composition comprising dry hydraulic cement, from about 0.05 to about 5.0 percent by weight, based on dry hydraulic cement, of a water-soluble polymer of methacrylamidopropyltrimethylammonium chloride, and sufficient water to form a pumpable slurry; and allowing the cement thus positioned to set to a monolithic mass; whereby loss of fluid from the cement slurry to the formation is reduced.
Claim 2
Independent Claim
90 words
A method of cementing a zone in a well penetrating a subterranean formation comprising injecting down the well and positioning in the zone to be cemented an hydraulic cement aqueous slurry composition comprising dry hydraulic cement, from about 0.05 to about 5.0 percent by weight, based on dry hydraulic cement, of a water-soluble polymer of methacrylamidopropyltrimethylammonium chloride, and sufficient water to form a pumpable slurry; and allowing the cement thus positioned to set to a monolithic mass; whereby loss of fluid from the cement slurry to the formation is reduced.
Claim 3
Dependent Claim
17 words
A method as in claim 1 wherein the polymer is a copolymer of acrylamide and methacrylamidopropyltrimethylammonium chloride.
References Cited (Backward Citations)
US3284393A
Cited
US3094501A
Cited
US3140269A
Cited
US3132693A
Cited
US3591542A
Cited
US3409080A
Cited
US3661880A
Cited
US3511314A
Cited
US3877522A
Cited
US3826311A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-03-16 | 1979-09-15 | 1980-03-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-03-16 | 1983-09-15 | 1984-03-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-03-16 | 1987-09-15 | 1988-03-16 | $7700.00 | Window Closed / Lapsed |