影響埋弧焊接不銹鋼(gang)管操作因素主要有以下兩點:
一、焊絲傾(qing)斜(xie)方向的影(ying)響(xiang)
焊絲傾斜方向分為前傾和后傾兩種,如圖4-21所示。焊絲傾角的大小不同,電弧對熔池的力和熱作用也就不同,從而影響到焊縫成形。當焊絲以一定傾角向后傾時,電弧力對熔池金屬的后緣作用減弱,熔池底部的金屬受熱減少,故熔深變淺,如圖4-21(c)所示。后傾角愈大,熔深愈淺,而熔寬增寬。相反,當焊絲做適當前傾時,可少許增加熔深。焊絲前傾斜通常較少采用,只有在特定情況下使用,如焊接小直徑圓筒形焊件的環焊縫時采用這種方法。
二(er)、焊(han)縫(feng)傾角(jiao)(inclination of weld axis,焊(han)縫(feng)軸(zhou)線與水平面(mian)之間的夾角(jiao))對焊(han)縫(feng)成形的影響
焊(han)(han)(han)(han)(han)件(jian)(jian)在傾(qing)斜位(wei)置焊(han)(han)(han)(han)(han)接(jie)時(shi),有上(shang)坡(po)(po)焊(han)(han)(han)(han)(han)和下坡(po)(po)焊(han)(han)(han)(han)(han)之分,如圖4-22所示。上(shang)坡(po)(po)焊(han)(han)(han)(han)(han)、下坡(po)(po)焊(han)(han)(han)(han)(han)對焊(han)(han)(han)(han)(han)縫成(cheng)(cheng)(cheng)形(xing)(xing)的(de)影響明(ming)顯地(di)不(bu)同。上(shang)坡(po)(po)焊(han)(han)(han)(han)(han)時(shi),焊(han)(han)(han)(han)(han)縫余(yu)高(gao)(gao)過(guo)高(gao)(gao),兩側易出現(xian)咬邊,焊(han)(han)(han)(han)(han)縫表面成(cheng)(cheng)(cheng)形(xing)(xing)明(ming)顯惡(e)化,實際工作(zuo)中(zhong)應避免采用(yong)上(shang)坡(po)(po)焊(han)(han)(han)(han)(han)。下坡(po)(po)焊(han)(han)(han)(han)(han)與上(shang)坡(po)(po)焊(han)(han)(han)(han)(han)相反,焊(han)(han)(han)(han)(han)縫的(de)熔深和余(yu)高(gao)(gao)均(jun)有所減小(xiao),而焊(han)(han)(han)(han)(han)縫寬度略有增加,焊(han)(han)(han)(han)(han)縫成(cheng)(cheng)(cheng)形(xing)(xing)得到改善。在焊(han)(han)(han)(han)(han)接(jie)圓筒焊(han)(han)(han)(han)(han)件(jian)(jian)的(de)內、外環焊(han)(han)(han)(han)(han)縫時(shi),一般(ban)均(jun)采用(yong)下坡(po)(po)焊(han)(han)(han)(han)(han),以減少發生燒穿的(de)現(xian)象,并改善焊(han)(han)(han)(han)(han)縫成(cheng)(cheng)(cheng)形(xing)(xing)。但焊(han)(han)(han)(han)(han)件(jian)(jian)下坡(po)(po)焊(han)(han)(han)(han)(han)的(de)角度過(guo)大(da)時(shi),熔深減小(xiao)可能產生未焊(han)(han)(han)(han)(han)透(tou)焊(han)(han)(han)(han)(han)接(jie)缺(que)陷。