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GB687242A
|
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Combined traveling pulley block and swivel connector
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GB689806A
|
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Pulldown device for rotary drilling apparatus
|
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US2644713A
|
|
Elevator grapple
|
|
US2657908A
|
|
Breakout table
|
|
US2578959A
|
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Hydraulic system for drilling rigs
|
|
US2609180A
|
|
Derrick
|
|
US2638932A
|
|
Pressure equalizer
|
|
US2534213A
|
|
Pulldown device for rotary drilling apparatus
|
|
US2472999A
|
|
Portable drilling rig
|
|
US2547254A
|
|
Valve
|
|
US2338093A
|
|
Kelly rod and drive bushing therefor
|
|
US2278606A
|
|
Transmission mounting for drilling rigs
|
|
US2343517A
|
|
Drilling rig
|
|
US2344383A
|
|
Shoring for portable drilling rigs
|
|
US2314323A
|
|
Rat-hole drilling attachment for rotary drilling rigs
|
|
US2334312A
|
|
Drilling machine
|
|
US2306800A
|
|
Piston
|
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US2232992A
|
|
Power take-off mounting
|
|
US2313861A
|
|
Drill pipe joint
|
|
US2283866A
|
|
Drilling rig
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