提高膨胀波纹管在弯曲井眼中应用可靠性研究

Research on reliability improving of expandable bellow application in crooked holes

刘鹏 陶兴华 胡彦峰 涂玉林

LIU Peng TAO Xinghua HU Yanfeng TU Yulin

中国石化石油工程技术研究院

SINOPEC Research Institute of Petroleum Engineering, Beijing 100101, China

膨胀波纹管技术在弯曲井段中受井眼条件的影响，国内一直未形成配套技术；国外虽然有成功应用的案例，但存在应用规模小、成功率不高等问题。为了确定膨胀波纹管适用的井眼条件，明确了井径、井斜角变化率和方位角变化率对其膨胀性能的影响规律。为了缩短井眼准备时间，提高封隔段井眼质量，推荐了多种扩眼工具。为了提高焊缝的承压能力，研发了端头整形装置，将端头形状误差缩小至1 mm以内；研制了自动焊接装置，减少了人为因素对焊接质量的影响，将焊接效率提高了8倍以上；形成了焊缝缺陷识别方法，识别精度最高可达0.01 mm，确定了不同类型缺陷在不同位置的临界失效尺寸。研制了适用于小井眼的机械膨胀工具和应对井下复杂情况的磨铣膨胀一体化工具。完善了膨胀纹波管在弯曲井眼中应用的施工工艺，降低了管串提前失效和膨胀不充分等风险。研究成果在2口井中成功应用，标志着形成了膨胀波纹管封隔弯曲井眼复杂地层的配套技术，为解决全井段复杂情况提供了新技术手段。

Due to the effect of the hole conditions in crooked hole sections, the support technology of expandable bellow hasn’t been formed in China. There are successful application cases abroad, but its application scale is small and its success ratio is low. In this paper, the influential laws of well diameter, hole deviation angle change rate and azimuth angle change rate on the expansion property of expandable bellow were defined in order to determine its applicable hole conditions. A variety of reaming tools were recommended to shorten the hole preparation time and improve the hole quality in sealed intervals. In order to increase the bearing capacity of the welding seams, an end shaping device was developed to keep the shape error of the end less than 1 mm. An automatic welding machine was developed to reduce the effects of artificial factors on the welding quality. By virtue of this device, the welding efficiency is increased by more than 8 times. A weld defect identification method with the maximum identification accuracy of 0.01 mm was developed, and it can be used to determine the critical failure size of different types of defects at different positions. The mechanical expansion tool suitable for slim holes and the milling-expansion integrated tool to deal with downhole complex situations were developed. The construction process of expandable bellow in crooked holes was improved and the risks of pipe string were reduced, e.g. early failure and insufficient expansion. The research results have been successfully applied in 2 wells. It is indicated that the support technology of expandable bellow for sealing the crooked holes in complex formations is formed and it provides a new technology for solving the complex situations in the full hole.

10.13639/j.odpt.2019.02.009