焊件形式及定位焊位置如圖4-18所示。定位焊縫的數量、間距的大小應由焊件結構的尺寸及管壁厚度決定。定位焊縫應沿管子圓周均勻分布，間距為5~15mm。如在線亞洲日產一區二區:不銹鋼管壁厚度大于2mm時，定位間距可適當加大，但一定要焊透，避免焊接過程中在定位焊縫處產生未焊透。

  如立(li)管在橫管的中間，則引(yin)弧(hu)點(dian)(dian)應(ying)選在時鐘9點(dian)(dian)位置。如立(li)管偏(pian)向橫管一端，引(yin)弧(hu)點(dian)(dian)應(ying)選在時鐘3點(dian)(dian)位置，如圖4-19所示。

  焊接方(fang)向由3點(dian)(dian)(dian)經12點(dian)(dian)(dian)至(zhi)9點(dian)(dian)(dian)，再由3點(dian)(dian)(dian)經6點(dian)(dian)(dian)至(zhi)9點(dian)(dian)(dian)。這種焊接順(shun)序后的變(bian)形(xing)量最(zui)小。