Modeling the Impact of Microinstrumentation in Microholes Wells and its Comparison with Conventional Casing

  • Ubedullah AnsariEmail author
  • YuanFang Cheng
  • Haris Ahmed Qureshi
  • Georgia
  • QingChao Li
Conference paper
Part of the Springer Series in Geomechanics and Geoengineering book series (SSGG)


Microhole or slim hole drilling technique not only saves the time of drilling but also reduces the cost of drilling dramatically. The problem with this technology is its least technical acceptance due to wellbore stability of small-sized wellbores. The comparative analysis is conducted on three different wellbore models plotted against various yield strength pressures for conventional and microhole wells. Three categories of casing grades with different casing sizes were selected to develop the wellbore models, and the comparison categories include conventional wellbore (J-K-55), microhole wellbore (J-K-55), and microhole well (P-110). The result showed that magnitudes of different yield strength pressures are 90% higher in case of microhole (P-110) model. Additionally, surface axial stress is calculated to decide what type of casing is best fit for small-diameter wellbore, and the outcomes proved that higher-grade casings can yield stress 3110 psi. Further, overall comparison revealed P-110 casing grades possess higher yield strength pressure except yield strength of the pipe body; for this parameter, the phenomenon is inverse due to smaller difference of internal and external diameters. Henceforward, this paper focuses on suggesting the suitable casing grade for microholes that can yield more pressures and stay stable for longer period.


Microhole Slim hole Drilling Comparative analysis Yield strength Casing 


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Copyright information

© Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  • Ubedullah Ansari
    • 1
    Email author
  • YuanFang Cheng
    • 1
  • Haris Ahmed Qureshi
    • 2
  • Georgia
    • 1
  • QingChao Li
    • 1
  1. 1.China University of PetroleumQingdaoChina
  2. 2.Mehran University of Engineering & TechnologyJamshoroPakistan

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