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US2362629A
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Aircraft compass-correcting apparatus
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US2336257A
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Method and apparatus for releasing jammed well-drilling tools
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US2354922A
|
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Portable derrick
|
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US2330592A
|
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Nozzle illuminating means
|
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US2300763A
|
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Portable well derrick
|
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US2331559A
|
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Portable derrick
|
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US2331558A
|
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Portable derrick
|
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US2313897A
|
|
Portable derrick
|
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US2267705A
|
|
Oil field apparatus
|
|
US2336305A
|
|
Portable derrick
|
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US2263943A
|
|
Insulated housing for gas holders
|
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US2307492A
|
|
Adjustable beam saddle
|
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US2270980A
|
|
Speed reducer casing
|
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US2280114A
|
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Safety switch for well pumping units
|
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US2218967A
|
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Counterbalancing device
|
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US2199586A
|
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Panel for building construction
|
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US2211965A
|
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Chain mechanism for connecting pump rods with walking beams
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US2175588A
|
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Walking beam counterbalance
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US2199583A
|
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Emergency control apparatus for well pumping and drilling mechanism
|
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US2176731A
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Folding mast for portable well drilling and operating apparatus
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