| 摘要 |
To erect metal utility poles, a plurality of tubular sections of utility poles are fabricated, each having tapered portions and the diameter of one being slightly larger than the diameter of another. The sections are brought to a site for erection and pulled together with short repeated strokes of a hydraulic cylinder attached to one section with its piston rod connected to another section of utility pole. In one embodiment it is not necessary to manually adjust the mechanism pulling the sections of utility poles together and in another embodiment, a light flexible cord is attached to one section and a hydraulic cylinder to another section. The hydraulic cylinder pulls the cord and when the piston rod is extended for the next retraction, the cord length is adjusted.
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