在原有破岩机械比能理论基础上,分析水力能量对破岩与井底净化起到的积极作用,建立水力参数条件下破岩比能模型,并完善相关理论。基于破岩比能模型与钻井参数和机械钻速的相互关系,通过分析钻进中井底工况,判断施加钻井参数的合理性,提出相应优化措施,并利用该模型预测机械钻速。结果表明:建立的破岩比能效率评价体系能够在钻前准确预测机械钻速、钻进中随钻诊断井底工况及优化参数、钻后优选钻头;该理论评价方法诊断准确率高、优化效果好且流程识别简单,具有良好的应用与推广价值。
Based on the original rock breaking machine specific energy theory,by analyzing the positive role of hydraulic energy on the rock breaking and bottom-hole clean,a rock breaking specific energy model was established under the conditions of the hydraulic parameters,and the relevant theory was perfected.Based on the relations between rock breaking specific energy model and drilling parameters and rate of penetration(ROP),appropriate optimizing measures were proposed by analyzing bottom-hole conditions of drilling and determining the reasonability of drilling parameters.Meanwhile,ROP can be predicted by further deducing the model.The results show that the established evaluation system of mechanical specific energy efficiency can accurately predict ROP before drilling,diagnose bottom-hole conditions and optimize parameter during drilling,and select bit after drilling.The theory assessment with highly diagnostic accuracy,effective optimizing and simple operation was demonstrated by field examples of rock breaking specific energy.Therefore,it is worthy to be applied and promoted.