| The problem of the ladder horizontal well drilling tool mechanics'calculation is always a key problem in the horizontal well. Because of the level of the ladder hole irregular curvature distribution, it will increase the friction, decline the capacity of drilling through, seriously, lead to the bit non-pressurized, drillstring destruction and other complex accident , not only relate to safety of drilling, but also increase oil and gas wells production cost. Currently, many domestic and foreign scholars have made many studies about the through capacity of the ladder horizontal well drill tool .The important part of the horizontal well optimization design is drillstring friction calculation . The study of horizontal well drillstring friction and torque helps improve the track design of horizontal wells, and conducive to rational design of the drillstring and BHA for trajectory control , monitoring and judging hole within the complex accident, conduciving the design of casing strength and guiding lowering casing and so on. Not only can put forward an accurate calculation and reasonable evaluation methods for the ladder horizontal wells drilling through capacity, but also put forward a study direction to solve the ladder horizontal drilling problems.In order to solve the problem of the friction, the through capacity of drilling evaluation, the drivers speed dial these effects design and construction scientificly and reasonably, this paper accoding to solid mechanics, drilling hole kinematic and kinetic theory, the overall drilling tool mechanical analysis, applys non-linear mechanical analysing the finite element method to solve drill tool mechanical model ,seeks the contact friction with the well , thus accomplishes the calculation and evaluation of the drilling through ability , making ladder Horizontal drilling design more scientific and rational, providing theoretical and technical assurance for drilling, forming a optimized design of the ladder horizontal well profile structure, a calculation and evaluation of the drilling through capacity. Solving these problems can ensure oilfield development program implement smoothly and be of great significance for improving the Daqing Oilfield multilayer thin reservoir development. |
