船舶基礎(chu)知識:造船業的噸位和排(pai)水量
為表(biao)(biao)(biao)示(shi)(shi)船(chuan)(chuan)舶(bo)的(de)大小,除用(yong)(yong)船(chuan)(chuan)長、船(chuan)(chuan)寬等尺度以外,通常用(yong)(yong)噸位(wei)。船(chuan)(chuan)舶(bo)噸位(wei)種(zhong)類繁雜又易混淆,主要有四種(zhong):①表(biao)(biao)(biao)示(shi)(shi)船(chuan)(chuan)舶(bo)的(de)重(zhong)量(liang),排水量(liang)噸;②表(biao)(biao)(biao)示(shi)(shi)船(chuan)(chuan)舶(bo)的(de)容積,用(yong)(yong)總噸(GT)或凈噸(NT)表(biao)(biao)(biao)示(shi)(shi);③表(biao)(biao)(biao)示(shi)(shi)裝(zhuang)載(zai)貨(huo)物的(de)重(zhong)量(liang),用(yong)(yong)載(zai)重(zhong)噸(DWT)表(biao)(biao)(biao)示(shi)(shi);④表(biao)(biao)(biao)示(shi)(shi)船(chuan)(chuan)舶(bo)建造(zao)工作量(liang),用(yong)(yong)修(xiu)正總噸(CGT)表(biao)(biao)(biao)示(shi)(shi)。
排(pai)水(shui)量(liang)噸:船(chuan)(chuan)舶(bo)(bo)(bo)浮在水(shui)面(mian)上時,排(pai)開水(shui)的(de)(de)重(zhong)量(liang)等于浮力(li),也等于船(chuan)(chuan)舶(bo)(bo)(bo)本身(shen)的(de)(de)重(zhong)量(liang)。因此(ci),排(pai)水(shui)量(liang)噸也就等于船(chuan)(chuan)舶(bo)(bo)(bo)的(de)(de)重(zhong)量(liang)。排(pai)水(shui)量(liang)噸在軍用艦艇(ting)上廣(guang)泛應用,但在民船(chuan)(chuan)上除待拆(chai)船(chuan)(chuan)舶(bo)(bo)(bo)用空載排(pai)水(shui)量(liang)噸(即輕噸,LDT) 作(zuo)為(wei)買賣(mai)廢船(chuan)(chuan)的(de)(de)尺度外,很少(shao)實際用作(zuo)新船(chuan)(chuan)度量(liang)單(dan)位(wei)。只是在中(zhong)國,對于非貨(huo)運船(chuan)(chuan)舶(bo)(bo)(bo)類的(de)(de)拖船(chuan)(chuan)、漁船(chuan)(chuan)、工程(cheng)船(chuan)(chuan)等,往往使用滿(man)載排(pai)水(shui)量(liang)噸作(zuo)為(wei)表示(shi)船(chuan)(chuan)舶(bo)(bo)(bo)大(da)小的(de)(de)單(dan)位(wei)。
載重(zhong)噸(dun)(DWT):是貨(huo)船可用于(yu)裝(zhuang)載貨(huo)物的最大營運噸(dun)位(wei)。一(yi)般指貨(huo)船在(zai)結構(gou)吃(chi)水或滿(man)(man)載吃(chi)水時裝(zhuang)載的貨(huo)物、淡水、燃(ran)料潤滑(hua)油、爐水、備品(pin)、供應(ying)品(pin)及人員、行(xing)李等噸(dun)位(wei)之和(空載排水量(liang)+載重(zhong)噸(dun)=滿(man)(man)載排水量(liang)噸(dun))。
總(zong)(zong)噸(dun)(dun)(dun)(GT):是(shi)國(guo)際通行的船舶(bo)計量(liang)單位(wei)之(zhi)一,是(shi)登記(ji)噸(dun)(dun)(dun)位(wei)的一種(zhong),主要用來衡量(liang)民用船舶(bo)的大小(容(rong)(rong)積)。總(zong)(zong)噸(dun)(dun)(dun)是(shi)指(zhi)各航海(hai)國(guo)家按(an)照《國(guo)際船舶(bo)噸(dun)(dun)(dun)位(wei)丈量(liang)公約》(1982年(nian)7月(yue)18日起實(shi)行)制(zhi)定的丈量(liang)規范丈量(liang)的船舶(bo)圍蔽(bi)處所(suo)的容(rong)(rong)積噸(dun)(dun)(dun)。
修(xiu)正(zheng)(zheng)(zheng)總(zong)(zong)(zong)噸(dun)(dun)(dun)(dun)(CGT):是(shi)國(guo)際通行(xing)(xing)的船(chuan)(chuan)(chuan)舶(bo)(bo)計量(liang)單位之一。在(zai)船(chuan)(chuan)(chuan)舶(bo)(bo)總(zong)(zong)(zong)噸(dun)(dun)(dun)(dun)基礎(chu)上考慮船(chuan)(chuan)(chuan)舶(bo)(bo)復雜度而(er)計算(suan)(suan)出的船(chuan)(chuan)(chuan)舶(bo)(bo)度量(liang)單位,計算(suan)(suan)方法為(wei):修(xiu)正(zheng)(zheng)(zheng)總(zong)(zong)(zong)噸(dun)(dun)(dun)(dun)GT=GT×C,其中(zhong)為(wei)GT總(zong)(zong)(zong)噸(dun)(dun)(dun)(dun)數,C為(wei)修(xiu)正(zheng)(zheng)(zheng)系(xi)數。中(zhong)國(guo)民(min)用(yong)(yong)鋼質船(chuan)(chuan)(chuan)舶(bo)(bo)修(xiu)正(zheng)(zheng)(zheng)系(xi)數按(an)船(chuan)(chuan)(chuan)舶(bo)(bo)行(xing)(xing)業標準《民(min)用(yong)(yong)船(chuan)(chuan)(chuan)舶(bo)(bo)修(xiu)正(zheng)(zheng)(zheng)噸(dun)(dun)(dun)(dun)計算(suan)(suan)》標準號(hao)為(wei)CB/T3484-2005確(que)定(ding)(ding)。目前國(guo)際上均按(an)0ECD造(zao)船(chuan)(chuan)(chuan)工作組1994年1月制定(ding)(ding)的修(xiu)正(zheng)(zheng)(zheng)系(xi)數表(biao)選用(yong)(yong)。修(xiu)正(zheng)(zheng)(zheng)總(zong)(zong)(zong)噸(dun)(dun)(dun)(dun)不僅比(bi)載重噸(dun)(dun)(dun)(dun)、總(zong)(zong)(zong)噸(dun)(dun)(dun)(dun)更能(neng)(neng)正(zheng)(zheng)(zheng)確(que)反(fan)(fan)映(ying)造(zao)船(chuan)(chuan)(chuan)工作量(liang)大小(xiao),同時還在(zai)一定(ding)(ding)程度上反(fan)(fan)映(ying)船(chuan)(chuan)(chuan)價高低和(he)產值大小(xiao)。因而(er),能(neng)(neng)比(bi)較正(zheng)(zheng)(zheng)確(que)地用(yong)(yong)來表(biao)示(shi)造(zao)船(chuan)(chuan)(chuan)產量(liang)、造(zao)船(chuan)(chuan)(chuan)工作量(liang)(新接(jie)船(chuan)(chuan)(chuan)舶(bo)(bo)訂(ding)(ding)單量(liang)和(he)手持訂(ding)(ding)單量(liang))和(he)造(zao)船(chuan)(chuan)(chuan)能(neng)(neng)力(li)。特(te)別是(shi)在(zai)產品(pin)結構(gou)差異(yi)很大的國(guo)家之間(jian)和(he)企業之間(jian)進行(xing)(xing)比(bi)較,用(yong)(yong)修(xiu)正(zheng)(zheng)(zheng)總(zong)(zong)(zong)噸(dun)(dun)(dun)(dun)作為(wei)統計單位比(bi)載重噸(dun)(dun)(dun)(dun)、總(zong)(zong)(zong)噸(dun)(dun)(dun)(dun)要準確(que)得多。
中國主要采(cai)(cai)用(yong)載(zai)重噸(dun)(dun)(dun)(dun)(DWT)和(he)(he)排(pai)水量噸(dun)(dun)(dun)(dun),而(er)國際(ji)上(shang)采(cai)(cai)用(yong)較(jiao)多(duo)是總噸(dun)(dun)(dun)(dun)(GT)、修正(zheng)(zheng)噸(dun)(dun)(dun)(dun)(CGT)。國際(ji)造船(chuan)(chuan)(chuan)(chuan)業,包(bao)括(kuo)造船(chuan)(chuan)(chuan)(chuan)企業、船(chuan)(chuan)(chuan)(chuan)級社、咨詢研(yan)究(jiu)機構(gou)和(he)(he)國際(ji)造船(chuan)(chuan)(chuan)(chuan)組(zu)(zu)(zu)織(zhi)(如經(jing)濟合作(zuo)與(yu)發(fa)展組(zu)(zu)(zu)織(zhi)(OECD)造船(chuan)(chuan)(chuan)(chuan)工作(zuo)組(zu)(zu)(zu)),在(zai)船(chuan)(chuan)(chuan)(chuan)舶生產總量的(de)統計(ji)(ji)(ji)中,較(jiao)少使用(yong)載(zai)重噸(dun)(dun)(dun)(dun)。只有一些大(da)型常規貨(huo)(huo)船(chuan)(chuan)(chuan)(chuan)的(de)造船(chuan)(chuan)(chuan)(chuan)公司為(wei)顯示(shi)其噸(dun)(dun)(dun)(dun)位大(da)而(er)采(cai)(cai)用(yong)載(zai)重噸(dun)(dun)(dun)(dun);一些咨詢研(yan)究(jiu)機構(gou)在(zai)統計(ji)(ji)(ji)貨(huo)(huo)運船(chuan)(chuan)(chuan)(chuan)舶時也有以(yi)載(zai)重噸(dun)(dun)(dun)(dun)為(wei)統計(ji)(ji)(ji)單(dan)位,但是他們更(geng)多(duo)地使用(yong)總噸(dun)(dun)(dun)(dun)和(he)(he)修正(zheng)(zheng)總噸(dun)(dun)(dun)(dun)。作(zuo)為(wei)當今世界重要的(de)國際(ji)造船(chuan)(chuan)(chuan)(chuan)組(zu)(zu)(zu)織(zhi)OECD造船(chuan)(chuan)(chuan)(chuan)工作(zuo)組(zu)(zu)(zu),在(zai)造船(chuan)(chuan)(chuan)(chuan)統計(ji)(ji)(ji)不(bu)使用(yong)載(zai)重噸(dun)(dun)(dun)(dun),而(er)只使用(yong)總噸(dun)(dun)(dun)(dun)和(he)(he)修正(zheng)(zheng)總噸(dun)(dun)(dun)(dun)。