Technology Analysis Of The Domestic Rig Used In CBM

At present, ordinary vertical spindle rig and rotary table rig are used in CBM at home. However, the effert of the drilling operations is not very good. Some of domestic institutions imported mobile full hydraulic top drive power head rig at abroad. In the process of actual use, these rigs have demonstrated their superiority, but the expensive price and long-period accessories supply make the rig difficult to maintain. Therefore, the CBM rig is urgently needed to be researched and developed which have independent intellectual property rights and suit for CBM development. But the research in this area is still in its infancy in China. There is no systematic analysis on what should be on the rig performance, what parameters should be selected and what kind of equipments should be matched, then the paper focused on solving the above-mentioned key issues.In response to these issues, the paper employs summarization, analysis and comparation methods. The paper summarizes the general situation of current rig, and studys requirements from geological conditions, drilling techniques and rig designs. In accordance with the rotary system, current rigs are divided into ordinary vertical spindle rig, rotary table rig and mobile full hydraulic top drive power head rig. From the drilling and construction requirements of the CBM wells, the paper discusses the structure and performance of current rigs respectively from the rotating, lifting, feeding and transmission system, and finds the gaps in structure, design, drilling capacity and drilling methods adaptability among ordinary vertical spindle rig, rotary table rig and mobile full hydraulic top drive power head rig, and considers that the reasons are the backward design philosophy and weak technical reserves in our country. After researching, this paper puts forward to the classification criteria and specific technical performance parameters of CBM rig, recommends the types of CBM rig that should be developed urgently, selects the appropriate equipment. At present, there has been no systematic analysis and studies for CBM rig on the types and parameters in our country, so the research of the paper is a new attempt, and this is also the innovation. In this paper, the parameters can be used as the proposal for the development of new CBM rig, and have some reference value in the follow-up construction of CBM exploration for the choice of rig and certain practical significance in further deepening and expanding the CBM exploration and development.