crown block

基本解释

To replace the drilling line wrapped around the crown block and traveling block.
爲更換纏繞在天車和遊動滑車周圍的鑽井鋼絲繩用。
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The drilling line is reeled over the crown block and traveling block to gain mechanical advantage in a "block and tackle" or "pulley" fashion.
鑽井用鋼絲繩通過天車和遊動滑車以滑輪組的形式獲得機械上傚益。
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The text detailedly introduced crown block, running system, availability work period of bridge girder erection equipment and improve case for precast beams install.
詳細介紹了對雙導梁式架橋機天車、行走系統、有傚工作長度及預制梁安裝就位的改進情況。

Strongly influenced behind the scenes by the Crown family of Chicago, which owned a controlling block of shares, the company sold off most of its military businesses when the Cold War ended in the biggest fire sale the defense sector had ever seen.
FORBES: General Dynamics Begins 2013 With New Leader, Changing Business Mix