【摘要】 提高小井眼水泥浆的顶替效率 ,是保证小间隙水泥环密封质量的重要因素之一。文章根据液体在小井眼、小间隙中的流动特点 ,采用理论和实验相结合的方法 ,对提高小间隙水泥浆顶替效率的几项基本因素 ,进行了深入的研究。研究突破了紊流和塞流的顶替概念 ,提出了如何控制水泥浆和钻井液的压力梯度及动切力的比值a和b ,来提高小间隙顶替效率的具体方法。文中还对提高小间隙水泥浆顶替效率的套管偏心度、紊流接触时间、钻井液触变性等指标提出了具体要求更多还原

【Abstract】 It is one of the important factors of ensuring the seal quality of cement sheath in a small clearance to raise slurry displacing efficiency in a slim hole.According to the flowing properties of liquids in the slim hole and small clearance,a deepgoing research on the basic factors of raising slurry displacing efficiency in the small clearance was carried out by use of the method of integrating theory with practice.This reseach has made a breakthrough in the displacing concepts of turbulent flow and plug flow and put forward a concrete method of how to raise the displacing efficiency in the small clearance through controlling slurry pressure gradient to drilling fluid pressure gradient ratio ( a ) and slurry yield point to drilling fluid yield point ration ( b ).In order to raise the slurry displacing efficiency in the small clearance,some concrete demands for these indexes as casing excentricity,turbulence contact time and drilling fluid thixotropy,etc.,are also proposed in the paper.更多还原