Ctr80 Composite Continuous Pipe Drill Injection Head Design And Analysis

With rapid development of global economy, the demand for oil and gas resources is increasing in the major industrial countries and the international crude oil supply-demand relation is intense. In order to deal with the status that international oil demand is rising unceasingly, many of the world’s oil companies, drilling companies and service companies are actively seeking one kind of new drilling technology and drilling equipment, which can further reduce the exploration and development expense and raise the economic efficiency. In the1990s, CTD (Coiled Tubing Drilling) technology is rapidly developed at North American, which is highly efficient and enviroument friendly with low cost and CTD has a list of advantages:(1) CTD do not need to connect the drill pipe and trip is fast.(2)During drilling, the mud can keep continuous circulation and it is easy to control downhole pressure.(3)CTD equiptment is portable and easy for transportation.(4)It is easy to implement automatic and intelligent drilling by using CTD.CTD has been one of the main development trend of drilling technology.So far CT technology has developed for nearly50years. Schlumberger, BJ Services and Halliburton occupy the60%CT service market.75%CT service is traditional well intervention and grows by10%～12%each year, while average annual growth rate of CT fracturing and CTD can reach30%, becoming the fastest-growing areas of coiled tubing technology and showing a strong development momentum. At present, CT technology in China has mainly used in well intervention, coiled tubing fracturing operations have started not long ago and the field of coiled tubing drilling is a blank. This is mainly due to the absence of dedicated coiled tubing drilling equipment, and the existing coiled tubing unit can not meet demand. This situation has severely constrained the application and development of coiled tubing drilling technology.In view of the above situation, the CTR80/200hybrid coiled tubing rig (CTR) used in shallow wells drilling is designed and its core equipment-ZRT80injector head is detailedly designed and analyzed in this article, which relies on the program "coiled tubing drilling technology research and supporting equipment development" sponsored by Sinopec Jianghan petroleum administration. The localization process of colied tubing rig is promoted through the research.Based on extensive investigations of the overseas situation of CTD technology、domestic market of CTD and application prospect, a CTD technical proposal whch is suitable for the domestic situations is put forward in this paper with consideration of development situation of domestic oil and gas resources, traditional casing program and the economy and transportation of coliled tubing. The suggestion is to give priority to develop the1200m coliled tubing rig which is used in drilling new wells with31/2in coliled tubing. Based on the overall plan of colied tubing rig, supporting equipment-ZRT80injector head is detailedly designed and analyzed. The solid modeling drawings of injector head components and assembly drawing are finished by Pro/E; Strength checks of key components are completed by FEA softwares and their reliability is verified; The bending of coiled tubing at the wellhead is analyzed and the results proved that the injector head has the ability to push the CT in the wellhole safely and prevent CT from bending; Based on strength checks, optimization design of the gripper block is completed including cross section parameters, bore dimension and tooth design in order to increase the frictional force between gripper block and CT, enhance the gripping reliability, noticeably improve gripping damage to CT caused by gripper block and reduce stress concentration and bending deflection of CT, which makes the CT operations safer and more reliable; Based on structure of the injector head, the hydraulic control system is designed to realize the whole funcition.In conclusion, a CTR proposal whch is suitable for the domestic oil and gas resources exploration is put forward in this paper based on extensive investigations of the overseas situation of CTR and drilling technology and the core equipment injector head is detailedly designed and analyzed, which has great significance and application value for the improvement of domestic CTD technology.