1. 卷邊圈制作方法(fa)
如圖2-53所示(shi),將鋼板圈置(zhi)于上下(xia)凹模之間,內凸模在外力的(de)(de)作用下(xia)將鋼板圈壓(ya)(ya)成卷(juan)邊(bian)圈。施力的(de)(de)機具可采(cai)用液壓(ya)(ya)千斤頂。當鋼板厚(hou)為3mm時(材質(zhi)為1Cr18Ni9Ti),100kN(10t)的(de)(de)液壓(ya)(ya)千斤頂可制(zhi)(zhi)(zhi)作公(gong)稱尺(chi)(chi)寸(cun)DN25mm的(de)(de)卷(juan)邊(bian)圈;當板厚(hou)3.5mm時,500kN(50t)液壓(ya)(ya)千斤頂可制(zhi)(zhi)(zhi)作公(gong)稱尺(chi)(chi)寸(cun)DN50mm的(de)(de)卷(juan)邊(bian)圈;當板厚(hou)4mm時,1000kN(100t)液壓(ya)(ya)千斤頂可制(zhi)(zhi)(zhi)作公(gong)稱尺(chi)(chi)寸(cun)DN80mm的(de)(de)卷(juan)邊(bian)圈。
在加工鋼板圈時,應使其內徑與管子外徑的比為(1:2.1)~(1:2.2)。
2. 卷邊短(duan)管(guan)的制(zhi)作
短(duan)管卷(juan)(juan)邊(bian)(bian)(bian)可(ke)采用(yong)電動(dong)卷(juan)(juan)邊(bian)(bian)(bian)機,其(qi)制(zhi)作方法如圖2-54所示。內模的(de)角(jiao)度a有45°、90°、125°、180°四種。在管子(zi)上卷(juan)(juan)邊(bian)(bian)(bian)時(shi),內模(中碳鋼(gang)制(zhi)成)更換4次,沖(chong)壓即(ji)成。短(duan)管卷(juan)(juan)邊(bian)(bian)(bian)比鋼(gang)圈(quan)卷(juan)(juan)邊(bian)(bian)(bian)麻煩些,但安裝方便。卷(juan)(juan)邊(bian)(bian)(bian)圈(quan)與管道焊接時(shi),常(chang)因焊縫高(gao)度較大,焊后要進行加工,否(fou)則會造成卷(juan)(juan)邊(bian)(bian)(bian)圈(quan)與鋼(gang)法蘭接觸不緊(jin)密的(de)缺陷。