An Experimental Study of Cuttings Transport in Directional Slim Hole Drilling

doi:2012.26.2.20

J. Ocean Eng. Technol. > Volume 26(2); 2012 > Article

J. Ocean Eng. Technol. 2012;26(2):20-25.
DOI: https://doi.org/10.5574/KSOE.2012.26.2.020

Han Sang-Mok,Kim Jeong-Hwan,Hwang Young-Kyu,Woo Nam-Sub,Kim Young-Ju

Jeollabuk-do Branch Institute KOMERI,Jeollabuk-do Branch Institute KOMERI,School of Mechanical Engineering Sungkyunkwan University,Mineral Resource Research KIGAM,Mineral Resource Research KIGAM

방향성 소구경 굴착의 입자 이송특성에 관한 연구

한상목,김정환,황영규,우남섭,김영주

한국조선해양기자재연구원 전북분원,한국조선해양기자재연구원 전북분원,성균관대학교 기계공학부,한국지질자원연구원 광물자원연구본부,한국지질자원연구원 광물자원연구본부

Keywords: Directional drilling, Slim hole drilling, Drilling fluid, Cuttings, Solid-liquid two phase flow

핵심용어: 방향성굴착, 소구경굴착, 굴착유체, 굴착암편, 고-액 2상 유동

Abstract

During drilling, the precipitation velocity of cuttings within an annulus depends on the density and configuration of the cuttings, and on the density, viscosity, and rheological characteristics of the drilling fluid. In directional drilling in particular, it is difficult to adjust and control the cuttings. In contrast to vertical drilling, it is very important to evaluate the flow characteristics of a drilling flow field. However, research on the transfer features of cuttings is inadequate. In this study, in order to identify transfer features of cuttings, an experiment was performed under wide-ranging conditions by constructing a slim hole annulus ($44mm{ imes}30mm$) device. In this experiment, the particle volume fraction were influenced by particle size, particle concentration within the flow, pipe rotation, flow volume, and inclination of the annulus. In addition, a mathematical formula for volumetric concentration was deduced and compared to the test results and behavior of cuttings under the other drilling condition was made to be predicted. Therefore, this study can provide meaningful data for vertical and horizontal drilling, and for directional drilling.