| 摘要 |
<p>A self-lifting platform has a rack forming the corner of one of its legs, and acts through pinions controlled by couplings secured to a beam. The beam is fixed to the platform on damping details, and these which act as guides are arranged between the vertical surfaces of the platform and beam whilst between the horizontal surfaces blocks of rubber are placed. When a self lifting platform is installed or its position changed, and when there is heavy wave action unusually heavy shock loading can be imposed on the lifting mechanism during the sinking or lifting of the legs. Particularly when the legs hit the sea bottom, they are lifted and dropped much more rapidly by the waves, than the normal operational lifting and lowering speeds. These shock loadings are damped and their number is reduced by an arrangement in which the beam carrying the rack is attached to the platform by elastic packings such as rubber blocks. This dampens the shock when the legs hit the bottom, whilst the hammering on the seabed is prevented by two couplings on each pinion which allow the leg to fall relatively to the platform, whilst preventing the platform falling relatively to the leg.</p> |
