| 摘要 |
Suspension members flexibly connected to a carriage and to an overhead support above the racking platform of an oil well mast or derrick support the carriage, which is provided with a floor to support a derrick man therein. The lower end of the suspension means can be swung back and forth parallel to the side of the mast or derrick and also at right angles to it to thereby move the carriage in the same directions, the carriage being provided with a lateral seat for receiving the upper end portion of a pipe and moving it with the carriage into another position.
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