Abstract:The coiled tubing reel is used to wind a steel pipe which is a few hundred to several thousands meters long. As compared with ordinary hydraulic winch based on active control speed and direction, the reel is passively control, and is required to move synchronously following the coiled tubing. Moreover because of coiled tubing's high rigidity, multiple pipe diameter and steel grade, reel needs to adapt to many different pipes winding orderly without loosening roll. At present, the control mode of ordinary hydraulic winch was used for reel's control, and the control requirements of reel could not be met very well. In order to further improve the reel's control performance, a closed hydraulic system with load feedback function was developed to realize the reel and the injector completely coordinated control by aimed at the original system's deficiency. The closed feedback control hydraulic system has the advantages of simple operation, high efficiency and less heat, which can effectively prevent the operation mistake, is safe and reliable, and can well meet the different coiled tubing's winding and following control requirements.