The trailer-mounted drilling rig is divided into mechanical drive, electrical drive and trailer-mounted drilling rig without ground anchor, of which the main characteristics are as follows: The drawworks of the trailer-mounted mechanical drive is driven by diesel engine and hydraulic transmission box, which has a proper matching and high transmission efficiency. For the electrical drive trailer-mounted rig, the drawworks and rotary table are driven by electrical motors£¬and the driving control is realized by a digital SCR/VFD systemThese drilling rigs have the following advantages: reasonable structure design, high-integration configuration and they only require a small working space. The main unit, drill floor, DP cat walk, generator set, pump set, solid control system, and auxiliary system of this kind rig can all be transported and moved by trailers. The drawworks is a double--drum type. The hydraulic disc brake is used as the main brake and water cooling thrust plate pneumatic brake or FDWS brake is used as the auxiliary brake.The mast is front-open type, which has a twin-body structure with an inclination angle mode or erective mode and can be raised or laid down and telescoped hydraulically. The drill floor has a two-section telescopic structure or parallelogram structure for easy transportation and lifting. The mast of the drilling rig without ground anchor is front-open, triple-section and front-inclination type with a height of 154ft, and it can perform triple-setback (columns) round-trip operations. The guyline is fixed on the drilling rig body, which saves disassembly and assembly time and reduces labor intensity.