Double-hoist hydraulic elevating derrick

The utility model discloses a double-hoist hydraulic elevating derrick which comprises a lifting cylinder, supporting legs, a pulley assembly, an adjusting screw rod and a three-position two-way hydraulic control valve, wherein the lifting cylinder is used for lifting the derrick; the pulley assembly is provided with three pulleys corresponding main and auxiliary hoisters, and the three pulleys are respectively used for elevating drive pipes and drill pipes on a chuck, thereby improving the drilling speed; the adjusting screw rod is used for carrying out micro-adjustment on the verticality and levelness of the derrick; and the three-position two-way hydraulic control valve is used for controlling and operating the elevating of the auxiliary hoister and the derrick. Because the derrick disclosed by the utility model can be arranged on various core drilling machines and respectively integrated with the core drilling machines, the traditional derrick-machine separation mode is changed, the functions of the drilling machines are expanded, and the frequent construction of the derrick in drilling engineering is avoided; meanwhile, an operation that the operating personnel climbs the derrick to carry out lifting and shackling conversion on the drive pipes and the drill pipes can be avoided, therefore, the derrick is easy to operate and convenient to maintain, and improves the operating efficiency and the personnel safety.