Research On Penetration Rate Equation Of Roller Bit Based On The Theory Of Invasion

In oil and gas industry, as a main rock breaking tool, the work performance of cone bitdirectly affects the drilling speed, drilling quality and drilling cost. Due to cone bit drillingvelocity model can reflect the law of various factors impact on the rate of penetration, itsstudy and application become one of the main task of drilling engineering. Base on thelaboratory experiment and drilling practice, scholars establish various drilling speed modeconsidering the different conditions and different methods by drilling rate mode study.During the Establishment of e drilling rate model, the influence of many parameters limitthe accuracy of the model and field applications. With constantly increasing difficulties in oilresources drilling, to a oil well optimization design, it is important to figure out the law ofvarious factors influence on the rate of penetration, identify suitable drilling rate mode topredict the penetration rate under the given conditions especially the adoption of new drillingtechniques and drilling technology (Such as directional, horizontal wells, extended reachwells, deep wells, slim hole technology).So carried out the cone drill speed mode research hasa very important theoretical significance and practical value.This article first takes invasive theory as a foundation, to analyze the rock break shapeunder single tooth invasion condition, obtains the relations between invasion load and therock breaking volume. Studies the rock characteristic and the teeth rock system bases onnumerical simulation to describe the impact of the change in the nature of the rockmicrostructure on the macroscopic mechanical properties in the process of the tooth invadethe rock under single tooth invasion condition.Through single tooth of the cone bit analysis, establish single tooth rock broken volumemodel and multi-tooth penetration rate model under pure rolling condition. Considering therelative sliding caused by cone overhang, cone complex and cone offset, establish the rollercone drill bit penetration rate model of roller bit under combined rock breaking condition. Atthe same time, analyze the impact of drilling parameters on the rate of penetration model suchas WOB and speed, and test comparative analysis.