УРБ-2,5 А, УРБ-2А-2 СКБ-41 well rig, Р-250 rotor: Р-150 rotor planetary pair, Р-150 rotor, flange, cup, shaft, half coupling, insertion piece, spindle, gear block, conical rotation pair, spindle, Р-250 rotor planetary pair, Р-410 rotor planetary pair, inner liner, U-shaped liner. The Р-150 rotor and the Р-250 rotor are designed for rotating the drilling tool and holding the string of drill and casing pipes when they are joined.