哈萨克斯坦H8309双分支水平井钻完井技术

摘要

哈萨克斯坦肯基亚克油区是世界上公认的难开采区块之一，该区块单井控油面积小、开发成本高，为此，决定通过钻探分支井技术解决该区块的技术难题。H8309井是中国石油海外第1口双分支水平井、该井开窗点较深，为克服深井高压、确保井壁稳定，采用了高密度钻井液（1.98 g/cm3）；为减小井控风险，首次使用了分支井造斜器分段打捞技术和深井分支井完井管柱丢手技术。双分支井眼都实施了酸化压裂增产改造措施。H8309井完井日产原油180 t，平稳运行138 d，是邻井水平井日产量的3倍。该井的成功实施为今后难产、难开发区块的高效开发提供了经验，为肯尼亚克油区的油气开采提供了新的技术方法，更为其他开发断块边部油藏、提高采收率、降低开发成本提供了强有力的技术支持。%The Kenkiyak Oilifeld in Kazakhstan is one of the world-recognized blocks dififcult to be produced. This block has small individual-well oil control area and high developmentcosts. Therefore, it is determined that the technical dififculties in this Block be tackled by branch well drilling technologies. Well H8309 is the ifrst overseas dual branch horizontal well of PetroChina, which has the deepest sidetracking point among overseas dual branch hozizonal wells.In order to overcome high pressure in deep wells and ensure wellbore stability, high density drilling lfuid (1.98 g/cm3)was used in this well;in order to reduce well control risks, this well used the sectional whipstock ifshing technology for branch wells and completion string release technology for deep branch wells for the ifrst time. The dual branch holes were both acid fractured. The H8309 Well lfowed at a rate of 180 tons of oil a day and maintained smooth produc-tion for 138 days, which is three times of daily production of adjacent horizontal wells. The success in this well provides experiences for the efifcient development of dififcult blocks, provides new approaches to the development of oil and gas in Kenkiyak oil province and provides strong support for developing faulted edge reservoirs, improving oil recovery and reducing development costs.