Abstract: The paper gives theresults of an experimental study transport of cutting in a horizontalwell.Eight kinds of drilling fluids are used.The cross design method is used for test design.The effects of annular fluid velocity,drillpipe rotation,eccentricity between drillpipe andwellbore,drilling rate,mud rheological properties,mud density and cutting size on cuttingstransport are taken into accounts.Variables having the most and the least significant effectson cutting-bed size are presented,as well as the effects of cross coupling between parame-ters.A empirical model of cutting-bed thickness is developed.After verifying the model by u-tilizing drilling data of seven horizontal wells,two centimeters cuttingbed height is prefer-able in safe drilling.As a result,the logical annular velocity is gained.Combined with the pre-vious researches and on-site horizontal wells drilling experience,the paper recommends holecleaning measures for horizontal well drilling.

Key words: horizontal wells, cuttings, model, annular space, drilling fluid

摘要： 采用八种不同流体作为携带岩屑的介质,利用正交设计法安排实验,对水平井段同心环空和偏心环空中钻井液携带岩屑的问题进行了实验研究.全面考虑了环空流体返速、钻具旋转、钻具与井限间的偏心度、钻进速度、岩屑粒径及泥浆性能对岩屑运移的影响.得到了影响岩屑运移的主要参数和次要参数,以及各因素间交互作用的影响,建立了水平井段岩屑床厚度的经验模式.利用7口水平井资料对模式进行了验证,提出了以2cm岩屑床厚度作为安全钻进时的合理厚度,并依次求出了合理环空返速的大小.结合现场实际情况及理论研究成果,推荐了水平井洗井措施.

关键词: 水平井, 岩屑, 模式, 环形空间, 钻井液