Ordinarycranes,usedintheconstructionindustryorforloadingships,canliftweightsofupto200t.Butconsiderthefollowingproblems:aprefabricated1,500tsectionofaship(suchasthewholesuperstructureorthefrontpartofthebow)hastobeplacedinitsfinalposition;a6,000trockethasto (共 6553 字) [閱讀本文] >>