J40 land drilling rig adopts 3-unit or 4-unit linkage via transmission of diesel engine + hydraulic torque converter or coupler ahead speed reducer; the winch drum is grooved; the main brake is hydraulic disc brake, and the auxiliary brake is electromagnetic eddy current brake;

1. It is driven in the form of 3-unit or 4-unit linkage via transmission of diesel engine + hydraulic torque converter or coupler ahead speed reducer;

2. The winch drum is grooved; the main brake is hydraulic disc brake, and the auxiliary brake is electromagnetic eddy current brake;

3. It is also equipped with an auxiliary hoisting device; and air-tube friction clutch is used for shift;

4. The part above and below the console of the winch are arranged separately, and the winch is installed on a low level;

5. The substructure is of a box-type structure or the structure of a swing-up front platform and a block back platform (the derrick floor of ZJ40/2250LDB drilling rig is of a box-on-box type structure);

6. The rotary table is independently driven by AC variable frequency motor or DC motor, and the rotary table can realize stepless speed regulation between 0-240 r/min;

7. Parallel operation of the compound chain box is realized by the parallel operation system; it is equipped with a cardan shaft driven large-power triplex single action mud pump;