油基钻井液性能与固井质量研究

为了研究油基钻井液性能和固井质量之间的直接关系，采用新建立的评价方法--人工岩心法，考察了油基钻井液体系及其主要组分对固井作业中第一、第二界面剪切胶结强度的影响规律，以及不同混浆比例下对水泥浆胶凝强度、初凝时间、终凝时间和水泥石抗压强度的影响规律。研究表明：对两界面胶结强度的影响由大到小依次是体系、乳状液、主乳化剂、降滤失剂、白油；前置液清洗后，胶结强度成倍提高，尤其对体系、乳状液和降滤失剂清洗效果最佳；随混浆比的增大，水泥浆初凝和终凝时间明显延长，水泥石抗压强度明显下降，甚至不凝。

RELATION BETWEEN OIL-BASE DRILLING FLUID PERFORMANCE AND CEMENT JOB QUALITY

In order to study the direct relation between oil base drilling fluid performance and cement job quality, a new developed evaluation method (artificial core method) was adopted; the effects of the oil base drilling fluid system and its main components on the shear cementing strengths of the first and second interfaces in cementing operation were investigated; and those of the different mix slurry ratios on the gel strength, initial set time, final set time of slurry and the compressive strength of bond cement were examined too. The study results indicated that, arranged in the order of magnitude, the degrees of the effects on the cementing strengths of the two interfaces were the system, emulsion, main emulsifier, fluid loss control agent and white oil respectively; the cementing strength would be doubled and redoubled after being cleaned by preflush, especially by the system, emulsion and fluid loss control agent; and, along with the increase in the mix slurry ratio, the initial and final set times of slurry would be obviously lengthened and the compressive strength of bond cement would be remarkably reduced or the slurry wouldn’t be even set.