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:
Jan. 28, 2003
Filed:
Oct. 20, 2000
Applicant:
Inventors:
Véronique Barlet-Gouedard, Chatenay Malabry, FR;
Fabien J. Brand, Paris, FR;
Pierre Maroy, Buc, FR;
Frederik Nilsson, Paris, FR;
Assignee:
Schlumberger Technology Corporation, Sugar Land, TX (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C04B 1/400 ;
U.S. Cl.
CPC ...
C04B 1/400 ;
Abstract
Systems for retarding setting in an oilfield well cement slurry comprise a solution of a phosphonate selected from methylene phosphonic acid derivatives and a phosphate, in particular selected from the following salts or the corresponding acids: mono-phosphates (ortho-phosphates PO ; meta-phosphates PO ), acyclic poly-phosphates (pyrophosphates P O , tripolyphosphates P O ) or cyclic poly-phosphates. The system preferably may also comprise a retarder booster and is more particularly applicable to cementing at low or medium temperatures.