英语翻译1.IntroductionCommercial ships carrying liquid cargo,suc

英语翻译
1.Introduction
Commercial ships carrying liquid cargo,such as liquefied
natural gas (LNG),liquefied petroleum gas (LPG),and crude oil,
can cause serious environmental pollution from the risk of
spillage.In an attempt to minimize such possibilities of spillage,
vessels such as very large crude oil carriers (VLCCs),bulk carriers
(B/C),and liquefied natural gas carriers (LNGCs) incorporate
double-hulled ship walls,as shown in Fig.1.These consist of outer
and inner walls,spaced 2- to 3-m apart; in this way,if the outer
wall is holed as a result of a collision or stranding,the inner wall
can still prevent the outflow of the liquid cargo [1].
However,the manufacture of double-hulled ships is more time
consuming and expensive than that of single-hulled vessels.Fig.2
also shows the manufacturing process used to obtain the closed
block that is a sub-module of the double-hulled ship wall.A
bottom shell and an open block are assembled separately using
welding processes where the bottom shell is composed of a wide
steel plate with several reinforcing longitudinal stiffeners welded
to it in parallel.Forming the closed block is more complicated;
first,a top shell,that is the same shape as the bottom shell,must
be manufactured.Then,a number of transverse web floors and
girders are welded on to the top shell; second,the open block is
turned over and placed alongside the bottom shell and each
longitudinal stiffener in the bottom shell is aligned with the
corresponding slit in the open block; and finally,third,the open
block is inserted laterally along the longitudinal stiffeners of the
bottom shell so that each stiffener slides into its corresponding
slit to assemble the closed block,as shown in Fig.2.The resulting
closed block must then be welded.That is,the welding has to be
done from inside the closed block,along the contacting bound-
aries of the top shell and the bottom shell.

1.介绍
商船承载液态货物、例如：液化天然气、液化石油气或原油等,可能会由于液货的溢流对环境造成污染.为了尽量减少货物溢出的可能性,船舶,如超大型油轮、散货船、液化气船应配置双层船壳,如图1所示.包括内板和外板,中间间隔2-3米.这样,即使外板因碰撞或搁浅破损,内板亦可以防止液货外流.
然而,相对于单壳船,双壳船的建造时间和费用会大得多,图2显示了一个双壳船闭合分段的制作流程,外板和开敞分段使用焊接工艺分别装配,船底板有纵向平行的加强材.成型的分段更为复杂,首先,和船壳板相同的舱底板必须预先造好,然后连接肋板和桁材焊接到舱底板上,其次,开敞的分段翻转并放置于底板旁边,底板的每个纵向加强材都应连接分段的开口.最后,将开敞分段从侧面沿底板的纵向加强材插入,使每个加强材插入到闭合分段的开口,如图2所示,最后进行焊接,成型的分段必须从内部沿舱底板和外板接缝进行焊接