锦16区块泥砂岩互层钻井液的研究与应用

Research and Application of Drilling Fluid for Mud Sandstone Interlayer in Jin16 Block

锦16区块老井侧钻,多为"S"型井,造成摩阻大、钻头传压困难;该区块上半部为造浆性泥岩为主,下半部以硬脆性泥岩为主,经常发生井眼缩颈、垮塌、钻头泥包、卡钻等井下复杂事故。针对这一问题,研制一套钻井液体系。通过室内实验表明,该体系在150℃老化前后均具有很强的润滑性能;通过膨润土造浆实验,表明该体系在造浆性泥页岩段能够保持良好的流变性;同时该体系抑制性能优良,失水造壁性能良好。在锦2-丙5-215C井的成功应用表明该体系能够有效解决锦16区块井下复杂情况,可进一步推广。

The lateral drilling of old well in Jin16 block is mostly ＂S＂ type well, resulting in big friction and the difficulty of bit transmission. The upper part of the block is mainly slurry mudstone; The lower part is mainly hard and brittle mudstone, underground complicated accidents often occur, such as hole shrinkage, collapse, bit balling and sticking. Aiming at this problem, a set of drilling fluid system has been developed. The laboratory experiments show that the system has strong lubrication performance before and after aging at 150 ℃. The bentonite slurry experiment shows that the system can maintain good rheological property in the slurry shale segment. At the same time, the system has good inhibiting performance and water-loss wall-building performance. The successful application of the system in Jin2-Bing5-215 C shows that the system can effectively solve the downhole complex situation in Jin16 block.