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:
Dec. 18, 1984
Filed:
Jul. 22, 1983
Robert L Graham, Baytown, TX (US);
Steven R Erbstoesser, Missouri City, TX (US);
Exxon Production Research Co., Houston, TX (US);
Abstract
A method of preventing overdisplacement and underdisplacement of proppant during well treatments to hydraulically induce and maintain a fracture in a subterranean formation traversed by a wellbore having a perforated casing. In the practice of the method, ball sealers are incorporated in the trailing end portion of a fracturing fluid-proppant slurry. The ball sealers have a density such that they do not sink in the slurry nor rise in the displacement fluid injected following the slurry. The ball sealers seat on at least some of the well perforations as the final portion of the slurry reaches the perforations. This causes the surface pumping pressure to increase, signalling the end of the treating operation. The detection of the time at which a selected portion of the injected fluid reaches the perforations allows the treatment to be terminated, minimizing proppant overdisplacement and providing for a fully packed fracture in the near-wellbore region. In another embodiment of the method, slurries of different densities are utilized, with the ball sealers having a density such that they remain at the interface between the slurries during the injection process.