求翻译：下封头与S3接管已组对并在焊接中。焊接时在焊接坡口处用电加热器对焊接坡口进行预热加温，先焊接基层的外坡口再焊接内坡口；焊接采用：SMAW（手工焊）；焊材：J507、Ф4mm；符合焊接工艺文件要求。是什么意思？

Lower head and s3 take over the group and welding. Welding in the welding groove at the electric heater to preheat the welding groove heated primary outer groove welding within the groove before welding; welding using the: smaw (manual welding); welding consumables: j507, Ф4mm; in line with the weld

The letter head and S 3 takes over the group and the solder. At the welding welding slope in the port of the welding with electric heaters warm up at first, the temperature of the grass-roots level welding, soldering, and Miter Hill; welding: SMAW (manual welding); welding supplies: J Ф 507, 4MM, we

Next shell cover and S3 control already group to and in welding.When welding uses electricity the heater butt weld bevel in the welding scarf place to carry on the preheating warming in, welds the basic unit the outside bevel to weld the bevel again first; Welding use: SMAW (manual welding); Welding

Sealing and welding head and S3 takes over group. When welding in welding Groove electric heater preheating heating for welding Groove, before welding the grass-roots level in the outer Groove weld Groove; welding: SMAW (welding), welding material: J507, ф 4mm; consistent with the documentation requ

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