Abstract: When a pipeline detection device is used in natural gas environment of high flow rate, its pigging efficiency and detection accuracy are both low. In order to solve these problems, the operational characteristics of detection devices in natural gas pipelines and the speed control methods that were commonly used for detection devices at home and abroad were analyzed. Result indicates that the carrying speed control device can effectively reduce the running speed of detection devices and the fluctuation amplitude of speed. The latest research progress of speed control devices based on bypass valves was overviewed in detail from the aspects of theoretical research, prototype tests and bypass valve structures. The composition, principle and commonly used structure forms of the speed control device based on bypass valve were analyzed. Results indicate that the future research on speed control devices based on bypass valve shall be focused on the relationship between loss coefficient of bypass valve and its opening forms and sizes. Besides, it is necessary to study how to keep the detection devices running continuously using safe lockout devices when speed control devices fail.