影響埋弧焊接不銹鋼管(guan)操作因素主要有以下兩點:
一、焊絲傾斜方向的影響(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、焊(han)縫(feng)傾角(inclination of weld axis,焊(han)縫(feng)軸線與(yu)水平面之間的(de)夾角)對焊(han)縫(feng)成形的(de)影響(xiang)
焊(han)(han)(han)(han)(han)(han)(han)(han)件(jian)在傾(qing)斜位(wei)置焊(han)(han)(han)(han)(han)(han)(han)(han)接時,有上(shang)坡(po)(po)(po)(po)焊(han)(han)(han)(han)(han)(han)(han)(han)和(he)下坡(po)(po)(po)(po)焊(han)(han)(han)(han)(han)(han)(han)(han)之分,如圖4-22所(suo)示。上(shang)坡(po)(po)(po)(po)焊(han)(han)(han)(han)(han)(han)(han)(han)、下坡(po)(po)(po)(po)焊(han)(han)(han)(han)(han)(han)(han)(han)對焊(han)(han)(han)(han)(han)(han)(han)(han)縫(feng)(feng)成(cheng)形(xing)(xing)(xing)的(de)影響明顯地不同(tong)。上(shang)坡(po)(po)(po)(po)焊(han)(han)(han)(han)(han)(han)(han)(han)時,焊(han)(han)(han)(han)(han)(han)(han)(han)縫(feng)(feng)余(yu)高過高,兩(liang)側易出現(xian)咬邊,焊(han)(han)(han)(han)(han)(han)(han)(han)縫(feng)(feng)表面(mian)成(cheng)形(xing)(xing)(xing)明顯惡(e)化,實際工作中(zhong)應(ying)避(bi)免采用(yong)上(shang)坡(po)(po)(po)(po)焊(han)(han)(han)(han)(han)(han)(han)(han)。下坡(po)(po)(po)(po)焊(han)(han)(han)(han)(han)(han)(han)(han)與(yu)上(shang)坡(po)(po)(po)(po)焊(han)(han)(han)(han)(han)(han)(han)(han)相反,焊(han)(han)(han)(han)(han)(han)(han)(han)縫(feng)(feng)的(de)熔(rong)深和(he)余(yu)高均(jun)有所(suo)減小(xiao),而(er)焊(han)(han)(han)(han)(han)(han)(han)(han)縫(feng)(feng)寬度略有增加,焊(han)(han)(han)(han)(han)(han)(han)(han)縫(feng)(feng)成(cheng)形(xing)(xing)(xing)得到改(gai)善。在焊(han)(han)(han)(han)(han)(han)(han)(han)接圓筒焊(han)(han)(han)(han)(han)(han)(han)(han)件(jian)的(de)內、外(wai)環焊(han)(han)(han)(han)(han)(han)(han)(han)縫(feng)(feng)時,一般均(jun)采用(yong)下坡(po)(po)(po)(po)焊(han)(han)(han)(han)(han)(han)(han)(han),以減少發生(sheng)燒穿的(de)現(xian)象,并改(gai)善焊(han)(han)(han)(han)(han)(han)(han)(han)縫(feng)(feng)成(cheng)形(xing)(xing)(xing)。但(dan)焊(han)(han)(han)(han)(han)(han)(han)(han)件(jian)下坡(po)(po)(po)(po)焊(han)(han)(han)(han)(han)(han)(han)(han)的(de)角度過大時,熔(rong)深減小(xiao)可能產生(sheng)未(wei)焊(han)(han)(han)(han)(han)(han)(han)(han)透焊(han)(han)(han)(han)(han)(han)(han)(han)接缺陷。