Temperature Requirements for Submerged Arc Welded (SAW) Straight Seam Steel Pipes and Causes of Slag Inclusion
In view of the fact that there are many inclusions in the raw materials and the slag inclusion in the weld, after taking measures such as inspection of the base metal before welding X60 weled steel pipe , replacement of welding wire and flux, etc., the proportion of slag inclusion in the fusion line of the weld is only slightly reduced, indicating that inclusions in the raw materials.
In view of the fact that there are many inclusions in the raw materials and the slag inclusion in the weld, after taking measures such as inspection of the base metal before welding X60 weled steel pipe , replacement of welding wire and flux, etc., the proportion of slag inclusion in the fusion line of the weld is only slightly reduced, indicating that inclusions in the raw materials. It is not the main cause of slag inclusions.
Temperature Requirements for Submerged Arc Welded (SAW) Straight Seam Steel Pipes
● Typically ranges between 100–250°C, depending on material thickness and grade, to minimize thermal stress and hydrogen-induced cracking.
● Preheating is mandatory for high-carbon steels (e.g., API 5L X70 and above) to ensure weldability.
● Controlled within 150–300°C to maintain weld pool stability and prevent rapid cooling-induced brittleness.
● Post-Weld Heat Treatment (PWHT):Applied for stress relief in critical applications (e.g., sour service pipelines), with temperatures held at 580–620°C for 1–2 hours.
Therefore, the main reason for the fusion line slag inclusion in the thick-walled straight seam submerged arc welded steel pipe is the improper selection of welding process parameters. The welding process parameters of the thick-walled LSAW steel pipe mainly include: g X60 weled steel pipe ,line energy, welding current, welding voltage, welding speed, welding wire spacing, groove size, etc.