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:
Apr. 25, 2017
Filed:
Oct. 13, 2016
China University of Petroleum (East China), Qingdao, Shandong, CN;
Baojiang Sun, Shandong, CN;
Xuerui Wang, Shandong, CN;
Yingwen Ma, Shandong, CN;
Yonghai Gao, Shandong, CN;
China University of Petroleum (East China), Shandong, CN;
Abstract
The present invention provides wellbore pressure control system and method for well cementation stages, and relates to the offshore oil and gas exploitation field. The wellbore pressure control system comprises: an injection pump; and a control device, configured to control the injection pump to inject a fluid or gas through an injection pipeline to a return pipeline that communicates with an annular space of the wellbore to decrease the pressure in the return pipeline and thereby decrease the pressure in the annular space, wherein, the density of the fluid or gas is lower than the density of a drilling fluid in the annular space. The technical scheme of the present invention can effectively prevent leaky zones from being fractured by high-density cement slurry in the well cementation process that may cause safety accidents such as well kick and well blowout, etc.