Mechanics in Engineering ›› 2014, Vol. 36 ›› Issue (1): 54-63.DOI: 10.6052/1000-0879-13-363

• Applied Research • Previous Articles     Next Articles

DETERMINATION OF WELLBORE INSTABILITY AREA AND ANALYSIS OF INFLUENCING FACTORS

WEI Kai1,2, MA Jinshan1, GUAN Zhichuan2, QI Jintao1, ZHANG Xiaochun3   

  1. 1 Drilling Technology Service Company, BHDC, Tianjin 300280, China;
    2 College of Petroleum Engineering, China University of Petroleum, Shandong, Qingdao 266580, China;
    3 Petroleum Engineering Research Institute, Dagang Oilfield Company, Tianjin 300280, China
  • Received:2013-08-29 Revised:2013-12-04 Online:2014-02-08 Published:2014-02-14

Abstract:

The wellbore safety factor is used as a criterion to determine the wellbore instability area, and with the Monte-Carlo simulation, the instability area is calculated. To consider the wellbore collapse risk, the influence of the mud density, the deviation and the azimuth on the wellbore instability area is analyzed, and the effect of the well trajectory parameters on the wellbore instability in different in-situ stress fields is evaluated by the method of calculating the instability area proposed in this paper. The evaluation results agree with the actual engineering practice, which shows that this method could be used to evaluate the characteristics and the severity of the borehole instability.

Key words:

wellbore stability|wellbore instability area|safety factor|Monte-Carlo simulation|well trajectory

CLC Number: