Patent ID: 8439127

Claim:
A drive apparatus and drill stem assembly of a de-coking system, comprising: a feeder ( 4 ) connected to a water supply ( 8 ) and to a drill stem ( 12 ), a drive ( 14 ) and a first gearbox ( 16 ) driven by the drive ( 14 ) for rotatably driving said feeder ( 4 ) and said drill stem ( 12 ), a tool ( 100 ) attached to the drill stem ( 12 ), the tool ( 100 ) generating high-pressure water jets ( 102 ), wherein said first gearbox ( 16 ) is an open, greased gearbox and has a gear ( 54 ) connected to an outer gear rim ( 52 ) of the feeder ( 4 ) for rotating the feeder ( 4 ) and the drill stem ( 12 ), wherein the drive ( 14 ) comprises a motor ( 56 ) and a second gear box ( 58 ) having an output gear ( 60 ) meshing with the gear ( 54 ), the second gear box ( 58 ) being driven by the drive ( 14 ), wherein the first gearbox ( 16 ) further comprises a skirt enveloping the gear pair being formed by the output gear ( 60 ) of the second gearbox ( 58 ) and the gear ( 54 ) completely, and wherein a lower side of the skirt is open.