The application   of drilling hole opener can improve the hole quality. Meanwhile,   it can save rig using time. Another benefit is the ability of continuous drilling, reducing the number of drilling and reaming. Therefore, the   benefit of drilling reamer is: can quickly drill a smooth implementation of concentric hole, reduce the losses of drilling rig caused by taking up much of rig time in lowering the casing, tripping and completion so as to achieve the completion ahead of schedule and cost savings.