Angle drilling apparatus
Angle drilling apparatus
Angular adjustment for drill rig mast
Arrangement for erecting and dismounting an elongate object havi
Boom articulating mechanism for aerial devices
Bottom brace for crane
Cable sling arrangement for pivoting a drilling mast and drawwor
Cantilevered mast drilling rig with single step erection
Carrier track assembly for extensible and retractable boom machi
Center guided crane boom
Column-mounted appliances
Compact sectionalized drilling mast, power arrangement and suppo
Construction apparatus with pivotable mast
Crane boom and telescopic section for it
Crane boom of trapezoidal boom sections having reinforcing rings
Crown bumper
Derrick having upper and lower crown block positions
Device for raising and lowering elongated support structures
Drilling derrick assembly
Drilling equipment tower raising mechanism