影響埋弧焊接不銹(xiu)鋼管操作因素主要有以下兩點:
一(yi)、焊絲傾斜方(fang)向(xiang)的影(ying)響
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、焊縫傾角(inclination of weld axis,焊縫軸線與水(shui)平(ping)面(mian)之間(jian)的夾角)對焊縫成形的影響
焊(han)(han)(han)(han)(han)(han)(han)件在傾斜位置焊(han)(han)(han)(han)(han)(han)(han)接(jie)時,有(you)上坡(po)焊(han)(han)(han)(han)(han)(han)(han)和(he)下(xia)坡(po)焊(han)(han)(han)(han)(han)(han)(han)之(zhi)分(fen),如圖4-22所(suo)示(shi)。上坡(po)焊(han)(han)(han)(han)(han)(han)(han)、下(xia)坡(po)焊(han)(han)(han)(han)(han)(han)(han)對焊(han)(han)(han)(han)(han)(han)(han)縫成(cheng)形(xing)(xing)(xing)的影(ying)響明(ming)顯地不同(tong)。上坡(po)焊(han)(han)(han)(han)(han)(han)(han)時,焊(han)(han)(han)(han)(han)(han)(han)縫余高過高,兩側易(yi)出現咬邊,焊(han)(han)(han)(han)(han)(han)(han)縫表面(mian)成(cheng)形(xing)(xing)(xing)明(ming)顯惡(e)化,實際工作中應避免采(cai)用上坡(po)焊(han)(han)(han)(han)(han)(han)(han)。下(xia)坡(po)焊(han)(han)(han)(han)(han)(han)(han)與(yu)上坡(po)焊(han)(han)(han)(han)(han)(han)(han)相反,焊(han)(han)(han)(han)(han)(han)(han)縫的熔(rong)深和(he)余高均(jun)有(you)所(suo)減(jian)(jian)小,而焊(han)(han)(han)(han)(han)(han)(han)縫寬(kuan)度略有(you)增加(jia),焊(han)(han)(han)(han)(han)(han)(han)縫成(cheng)形(xing)(xing)(xing)得到改善。在焊(han)(han)(han)(han)(han)(han)(han)接(jie)圓(yuan)筒焊(han)(han)(han)(han)(han)(han)(han)件的內(nei)、外環焊(han)(han)(han)(han)(han)(han)(han)縫時,一般均(jun)采(cai)用下(xia)坡(po)焊(han)(han)(han)(han)(han)(han)(han),以減(jian)(jian)少發生(sheng)燒穿(chuan)的現象,并(bing)改善焊(han)(han)(han)(han)(han)(han)(han)縫成(cheng)形(xing)(xing)(xing)。但焊(han)(han)(han)(han)(han)(han)(han)件下(xia)坡(po)焊(han)(han)(han)(han)(han)(han)(han)的角度過大時,熔(rong)深減(jian)(jian)小可(ke)能產生(sheng)未焊(han)(han)(han)(han)(han)(han)(han)透(tou)焊(han)(han)(han)(han)(han)(han)(han)接(jie)缺陷。


