蝶(die)形(xing)(xing)(xing)封頭(tou)外(wai)形(xing)(xing)(xing)的要(yao)求： JB/T4746 封頭(tou)標準劃定(ding)： 1、 封頭(tou)必需用全樣(yang)板搜檢外(wai)形(xing)(xing)(xing)。 2、 外(wai)形(xing)(xing)(xing)公役：外(wai)凸(tu)不(bu)年(nian)夜(ye)于1.25%Di，壓力容(rong)器碟形(xing)(xing)(xing)封頭(tou)，內凹不(bu)年(nian)夜(ye)于0.625%Di。 3、 過(guo)渡段內半徑不(bu)得小于圖樣(yang)劃定(ding)值(zhi)(zhi)(zhi)。 4、 球面體：曲率巨(ju)細影響封頭(tou)厚度(du) 5、 過(guo)渡段：降(jiang)低球面與(yu)筒體毗連的峰(feng)值(zhi)(zhi)(zhi)應(ying)力 6、 直(zhi)邊：禁(jin)止過(guo)渡段峰(feng)值(zhi)(zhi)(zhi)應(ying)力與(yu)筒體組對的焊接應(ying)力疊加(jia)

       碟(die)(die)形(xing)(xing)封(feng)(feng)(feng)(feng)頭(tou)，又稱帶折(zhe)邊球形(xing)(xing)封(feng)(feng)(feng)(feng)頭(tou)，碟(die)(die)形(xing)(xing)封(feng)(feng)(feng)(feng)頭(tou)價格，又名蝶形(xing)(xing)封(feng)(feng)(feng)(feng)頭(tou)。由一(yi)個球面、一(yi)個某(mou)一(yi)高度的(de)(de)圓筒直(zhi)邊和連接以(yi)上兩個部(bu)分(fen)的(de)(de)曲(qu)(qu)(qu)率半徑大小小于(yu)球面半徑的(de)(de)過渡部(bu)分(fen)組成。碟(die)(die)形(xing)(xing)封(feng)(feng)(feng)(feng)頭(tou)為一(yi)個連續曲(qu)(qu)(qu)面，在三部(bu)分(fen)連接處，經線(xian)曲(qu)(qu)(qu)率半徑有突變，由于(yu)曲(qu)(qu)(qu)率變化， 因而存在著(zhu)彎(wan)曲(qu)(qu)(qu)應(ying)力。彎(wan)曲(qu)(qu)(qu)應(ying)力和拉(la)伸應(ying)力疊加(jia)(jia)的(de)(de)結果，使這部(bu)分(fen)的(de)(de)應(ying)力突出于(yu)其他部(bu)分(fen)。與橢圓形(xing)(xing)封(feng)(feng)(feng)(feng)頭(tou)相比，應(ying)力分(fen)布不(bu)如其均勻，但加(jia)(jia)工較之(zhi)容易，因而在工程使用中并不(bu)理想。但當橢圓形(xing)(xing)封(feng)(feng)(feng)(feng)頭(tou)的(de)(de)模具加(jia)(jia)工有困難(nan)時(shi)，則用碟(die)(die)形(xing)(xing)封(feng)(feng)(feng)(feng)頭(tou)代替。

       橫(heng)梁(liang)(liang)的(de)主要(yao)構件頂(ding)板(ban)(ban)(ban)(ban)(ban)(ban)、腹板(ban)(ban)(ban)(ban)(ban)(ban)、 底板(ban)(ban)(ban)(ban)(ban)(ban)各有三(san)塊(kuai)板(ban)(ban)(ban)(ban)(ban)(ban)拼(pin)接(jie)而成，且均為全焊(han)(han)透焊(han)(han)縫(feng)。在組裝(zhuang)前對拼(pin)接(jie)板(ban)(ban)(ban)(ban)(ban)(ban)的(de)坡口應(ying)(ying)嚴酷(ku) 搜檢(jian)，貴州碟(die)形封頭(tou)，合(he)適要(yao)求后(hou)方可(ke)進(jin)行組裝(zhuang)焊(han)(han)接(jie)。具體焊(han)(han)接(jie)工藝步伐如下: (1)橫(heng)梁(liang)(liang)的(de)頂(ding)板(ban)(ban)(ban)(ban)(ban)(ban)、底板(ban)(ban)(ban)(ban)(ban)(ban)和腹板(ban)(ban)(ban)(ban)(ban)(ban)在拼(pin)接(jie)時(shi)，都應(ying)(ying)使(shi)深坡口向上，且上口應(ying)(ying)確(que)保平 齊，兩(liang)(liang)側長邊也應(ying)(ying)平齊，并(bing)要(yao)求不(bu)銹(xiu)鋼彎頭(tou)對接(jie)縫(feng)的(de)兩(liang)(liang)頭(tou)安(an)置(zhi)引弧板(ban)(ban)(ban)(ban)(ban)(ban)和引出板(ban)(ban)(ban)(ban)(ban)(ban)。 (2)橫(heng)梁(liang)(liang)兩(liang)(liang)頭(tou)的(de)定位(wei)焊(han)(han)應(ying)(ying)不(bu)小(xiao)(xiao)于200 mm，定位(wei)焊(han)(han)的(de)焊(han)(han)腳尺(chi)寸不(bu)小(xiao)(xiao)于 6 mm，要(yao) 求腹板(ban)(ban)(ban)(ban)(ban)(ban)雙面進(jin)行同樣尺(chi)寸的(de)定位(wei)焊(han)(han)。腹板(ban)(ban)(ban)(ban)(ban)(ban)中心的(de)定位(wei)焊(han)(han)長度(du)不(bu)小(xiao)(xiao)于75 mm，間距 為250一300 mm，接(jie)納雙面交織定位(wei)焊(han)(han)，焊(han)(han)腳尺(chi)寸年夜于4 mm. (3)底板(ban)(ban)(ban)(ban)(ban)(ban)與腹板(ban)(ban)(ban)(ban)(ban)(ban)定位(wei)焊(han)(han)時(shi)，碳鋼碟(die)形封頭(tou)，需按劃定預熱至100一150’C，為使(shi)厚板(ban)(ban)(ban)(ban)(ban)(ban)(年夜于 300 mm)預熱平均，淘汰(tai)應(ying)(ying)力，應(ying)(ying)同時(shi)擺(bai)設三(san)塊(kuai)電加熱板(ban)(ban)(ban)(ban)(ban)(ban)。 (4)橫(heng)梁(liang)(liang)拼(pin)板(ban)(ban)(ban)(ban)(ban)(ban)對接(jie)前，應(ying)(ying)先搜檢(jian)不(bu)銹(xiu)鋼三(san)通定位(wei)焊(han)(han)縫(feng)是否有裂紋，在確(que)認無裂紋后(hou)方可(ke)正 式焊(han)(han)接(jie)。