PDC钻头泥包的识别及其录井参数特征

The distinction of the PDC bit balling and its features of mud logging parameters

PDC钻头的高钻速和耐磨性,为提高钻井时效创造了条件,但在某些地层中PDC钻头在钻进过程中容易发生钻头泥包,不仅影响钻进速度,而且可能引发井喷。针对此问题,开展录井现场的实时评价、及时发现与识别PDC钻头泥包,是综合录井的重要工作之一。在PDC钻头钻进过程中对录井参数及曲线的异常变化进行实时监测,可及时发现钻头泥包,通过实例分析,总结出PDC钻头发生泥包时综合录井参数变化特征,阐述了钻头泥包与钻头老化的异同点,提出了钻头泥包的识别方法和步骤,在实际应用中取得了很好的效果,为拓展综合录井仪在钻井工程预报中的作用进行了有益的探索。

The high rate penetration and abradability create the condition for increasing the drilling efficiency,however,the drilling balling may easily occur during drilling with PDC bit in some formations,which may not only influence drilling rate,but also induce well blow out.In accordance with the problem,it is necessary to carry out the real time evaluation at mud logging site to discover and distinguish PDC bit balling in time.During PDC bit drilling,a bit balling can be noticed in time by monitoring the abnormal changing in mud logging parameters and curves in real time.The authors summarized the logging parameters changing features at the time of PDC bit balling by the practical examples,described the similarities and differences between the bit balling and bit ageing,and put forward the distinguishing methods and procedures of bit balling,which had got excellent results in the practical application and had been beneficial to probe into expanding the functions of comprehensive mud logging unit in drilling engineering prediction.