US4258790A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Well cementing method using low fluid-loss cement slurry
Assignee: BJ Services Co USA
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Filing: 1979-01-24
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Granted: 1981-03-31
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Expires: 1999-01-24
Abstract
Abstract An improved fluid loss additive for use in well cements, preferably comprising from about 30 to about 70 weight percent polyvinylpyrrolidone, from about 5 to about 19 weight percent carboxymethylhydroxyethyl cellulose, and the sodium salt of naphthalene sulfonate. Improved cement slurries comprising the subject fluid loss additive and an improved method for cementing well bores through use of the novel slurries are also provided. The improved cement slurries of the invention preferably comprise from about 26 to about 60 percent water and from about 0.75 to about 2 percent of the improved fluid loss additive, by weight of the cement.
Inventors
- 👤 Billy W. Hale
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:41
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/42; C09K8/46; C09K8/467; C09K8/487; C04; C04B; C04B28/00; C04B28/02; C04B2103/00; C04B2103/46
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
117 words
In a method for cementing a subterranean well bore wherein a cement slurry is pumped downwardly through the well bore within the well casing, out through the open lower end of the casing, then upwardly in the annulus between the well casing and the wall of the well bore, the improvement consisting of utilizing a cement slurry comprising cement, from about 26 to about 60 percent water, and from about 0.75 to about 2 weight percent fluid loss additive, by weight of the cement, wherein said fluid loss additive further comprises from about 30 to about 70 weight percent polyvinylpyrrolidone, from about 5 to about 19 weight percent carboxymethylhydroxyethyl cellulose, and the sodium salt of naphthalene sulfonate.
Claim 2
Dependent Claim
117 words
In a method for cementing a subterranean well bore wherein a cement slurry is pumped downwardly through the well bore within the well casing, out through the open lower end of the casing, then upwardly in the annulus between the well casing and the wall of the well bore, the improvement consisting of utilizing a cement slurry comprising cement, from about 26 to about 60 percent water, and from about 0.75 to about 2 weight percent fluid loss additive, by weight of the cement, wherein said fluid loss additive further comprises from about 30 to about 70 weight percent polyvinylpyrrolidone, from about 5 to about 19 weight percent carboxymethylhydroxyethyl cellulose, and the sodium salt of naphthalene sulfonate.
Claim 3
Dependent Claim
23 words
The improved method of claim 1 wherein said slurry comprises from about 38 to about 48 percent water, by weight of the cement.
Claim 4
Dependent Claim
25 words
The improved method of claim 2 wherein said slurry comprises from about 1 to about 1.5 percent fluid loss additive, by weight of the cement.
Claim 5
Dependent Claim
15 words
The improved method of claim 1, 2 or 3 wherein said cement is Portland cement.
Claim 6
Dependent Claim
21 words
The improved method of claim 1, 2 or 3 wherein said cement is a mixture of Portland cement and lightweight cement.
Claim 7
Dependent Claim
16 words
The improved method of claim 1, 2 or 3 wherein said slurry further comprises a retarder.
Claim 8
Dependent Claim
12 words
The improved slurry of claim 6 wherein said retarder is zinc borate.
Claim 9
Dependent Claim
25 words
The improved method of claim 7 wherein said retarder is present in an amount ranging up to about 0.4 percent by weight of the cement.
Claim 10
Dependent Claim
16 words
The improved method of claim 1, 2 or 3 wherein said slurry further comprises an accelerator.
Claim 11
Dependent Claim
28 words
The improved method of claim 9 wherein said accelerator is present in an amount ranging up to about 6 percent by weight of the water in said slurry.
Claim 12
Dependent Claim
12 words
The improved method of claim 9 wherein said accelerator is potassium chloride.
Claim 13
Dependent Claim
16 words
The improved method of claim 1, 2 or 3 wherein said slurry further comprises a defoamer.
Claim 14
Dependent Claim
27 words
The improved method of claim 12 wherein said defoamer is present in an amount ranging from about 0.1 to about 0.3 percent by weight of the cement.
Claim 15
Dependent Claim
27 words
The improved method of claim 1, 2 or 3 wherein said slurry further comprises from about 20 to about 50 percent sand, by weight of the cement.
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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) | 1984-03-30 | 1984-09-29 | 1985-03-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-30 | 1988-09-29 | 1989-03-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-30 | 1992-09-29 | 1993-03-31 | $7700.00 | Window Closed / Lapsed |