化工材料貯運罐先前是用普通鋼制成罐體后再在其內面涂層防腐。1980年IMO(國際海事協會)制定的船運化工材料貯運罐的裝載條件,增加了對大罐清洗難易程度的要求。從各種船運裝載條件可能性方面考慮,在國際航運船中,多數采用不銹(xiu)鋼制造的大罐。隨后在國內航運船方面的大罐亦采用不銹鋼制造。當初開始使用的鋼種為SUS304和SUS304不銹鋼復合板,其后許多航運裝載化學藥品(化工材料)貯運的大罐多采用SUS316、SUS316L、SUS316不銹鋼復合板。
所(suo)謂不(bu)(bu)銹(xiu)鋼(gang)(gang)復(fu)(fu)合(he)板(ban)(ban)(ban)(ban)(ban)(ban),即不(bu)(bu)銹(xiu)鋼(gang)(gang)板(ban)(ban)(ban)(ban)(ban)(ban)生(sheng)產(chan)廠將(jiang)不(bu)(bu)銹(xiu)鋼(gang)(gang)板(ban)(ban)(ban)(ban)(ban)(ban)和(he)普通鋼(gang)(gang)板(ban)(ban)(ban)(ban)(ban)(ban)的(de)(de)(de)(de)半成(cheng)(cheng)品的(de)(de)(de)(de)板(ban)(ban)(ban)(ban)(ban)(ban)面(mian)貼(tie)合(he)在一起,在保(bao)持真空狀態下,將(jiang)貼(tie)合(he)面(mian)的(de)(de)(de)(de)周圍進(jin)行焊接(jie),再將(jiang)焊好夾層板(ban)(ban)(ban)(ban)(ban)(ban)的(de)(de)(de)(de)半成(cheng)(cheng)品進(jin)行加(jia)熱,在軋(ya)板(ban)(ban)(ban)(ban)(ban)(ban)機(ji)上按厚(hou)板(ban)(ban)(ban)(ban)(ban)(ban)軋(ya)制工(gong)藝軋(ya)成(cheng)(cheng)不(bu)(bu)銹(xiu)鋼(gang)(gang)和(he)普通鋼(gang)(gang)相(xiang)結合(he)的(de)(de)(de)(de)所(suo)謂復(fu)(fu)合(he)板(ban)(ban)(ban)(ban)(ban)(ban)。從(cong)船(chuan)體(ti)和(he)大罐(guan)的(de)(de)(de)(de)焊接(jie)作業(ye)等(deng)方(fang)面(mian)考慮,船(chuan)體(ti)側壁和(he)傳遞板(ban)(ban)(ban)(ban)(ban)(ban)使用復(fu)(fu)合(he)板(ban)(ban)(ban)(ban)(ban)(ban),前后隔(ge)板(ban)(ban)(ban)(ban)(ban)(ban)和(he)中心隔(ge)板(ban)(ban)(ban)(ban)(ban)(ban)多數還是使用不(bu)(bu)銹(xiu)鋼(gang)(gang)板(ban)(ban)(ban)(ban)(ban)(ban)。大貯罐(guan)中的(de)(de)(de)(de)隔(ge)板(ban)(ban)(ban)(ban)(ban)(ban),為了增加(jia)罐(guan)體(ti)的(de)(de)(de)(de)強(qiang)度可(ke)以(yi)加(jia)工(gong)成(cheng)(cheng)波(bo)浪形(xing)狀使用。
化工(gong)材料(liao)貯運(yun)船,分類為小(xiao)型國(guo)(guo)內(nei)運(yun)輸船和中(zhong)(zhong)型、大(da)(da)型的國(guo)(guo)際運(yun)輸船,在(zai)日(ri)本所建造(zao)的大(da)(da)多數是中(zhong)(zhong)型國(guo)(guo)際化工(gong)材料(liao)貯運(yun)大(da)(da)罐運(yun)輸船,歐洲(zhou)建造(zao)則多數都是大(da)(da)型的。例(li)如(ru),這種大(da)(da)型船是從非洲(zhou)裝載磷酸運(yun)往印度或中(zhong)(zhong)國(guo)(guo)等(deng),卸載以后,清洗(xi)干(gan)凈,再在(zai)附近港口裝載其他藥(yao)品(pin),往返于不同(tong)國(guo)(guo)家的港口之間(jian)。
中型(xing)國際(ji)航運化(hua)工材料貯運大(da)罐(guan)船,大(da)約(yue)為2萬噸(dun)級(ji),船長度為約(yue)150米,寬度約(yue)25米,左舷放置(zhi)(zhi)十個大(da)罐(guan),右舷放置(zhi)(zhi)十個大(da)罐(guan),共(gong)計20個大(da)罐(guan)。大(da)罐(guan)容(rong)量要(yao)(yao)符合船的裝載量要(yao)(yao)求。為了使化工材料貯運大罐的容量增大就要減輕船體重量,重要途徑是使用高強度的材料,減少板材厚度。為此大多數使用了SUS316L不銹鋼和SUS317L不銹鋼牌號中添加氮,具有高強度和高耐腐蝕性的材料。目前,這種SUS316LN不銹鋼和SUS317LN已經標準化了。在歐洲這種大型化工材料貯運大罐運輸船,多使用強度和耐腐蝕性俱佳的奧氏體/鐵素體雙相不(bu)銹鋼材料。