The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 07, 1989
Filed:
Sep. 04, 1987
David B Larson, Broken Arrow, OK (US);
Erik B Nelson, Broken Arrow, OK (US);
Dowell Schlumberger Incorporated, Tulsa, OK (US);
Abstract
A novel method and device for manipulating ferrofluids for use in cementing wells are disclosed. The cementitious fluids may comprise: (a) a hydraulic cement, (b) finely divided magnetic particles, (c) a binding agent or a surfactant, and (d) a liquid medium. The binding agent or surfactant is present in the compositions in an amount sufficient to render the compositions stable in a magnetic field. When used in cementing wells, the cementitious ferrofluids are implaced in the annulus separating a casing from the formation in a wellbore by conventional techniques and the slurry is subsequently subjected to an activating alternating magnetic field that causes movement of the flurry. The non-cementitious ferrofluids comprise: (a) finely divided magnetic particles, (b) stabilizing agent, and (c) a liquid medium. The movement of the slurry results in a 'scrubbing' action against the surface of the casing and formation surfaces, and a mixing of the slurry which helps displace any residual drilling mud. The net result is better bonding of the cement to the casing and formation.