... frequency driven.Main components/parts,such as a crown block,traveling block,hook,swivel, rotary table,mast & substructure are in compliance with API ... . 5.as required, drilling floor can be the structure of block assembled or self-propelled. ParametersModelZJ40/2250 D/DB/L/LDBNominal ... of travelling system mm(in)1120 (44)Internal dia. Of swivel stem mm(in)75 (3)Drawworks power rating kW(hp ...