drilling performance is fit for specification of API Spec 4F,7K,8A, ... and the Eaton auxiliary braking device. While for hoister, drill pump, and drum, all adopt independent electric driving, infinite speed regulation ... electromagnetic eddy current device etc, for hoister, drum, drill pump, all adopt unified driving; the derrick adopts A type or ... 16)7.5(25)7.5(25) 9(30)drilling performance oil drilling ...