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:
Jun. 10, 2003
Filed:
Oct. 04, 2001
James W. Dobson, Jr., Houston, TX (US);
Kim O. Tresco, Houston, TX (US);
Texas United Chemical Company, LLC., Houston, TX (US);
Abstract
Disclosed is a method of increasing the low shear rate viscosity and the shear thinning index of aqueous fluids containing a divalent cation salt, a crosslinked amylopectin starch which functions as both a viscosifier/suspending agent and as a fluid loss control additive, and a bridging agent, the fluids resulting from the method, and the use of the fluids in drilling a well, wherein the bridging agent is a sized particulate magnesium carbonate or a mixture of sized magnesium carbonate and sized calcium carbonate. The median (D ) particle size of the magnesium carbonate is from about 2 &mgr;m to about 10 &mgr;m. The weight ratio of calcium carbonate to magnesium carbonate is from about 70/30 to about 0/100.