Thick-walled straight seam welded pipes refer to steel pipes with a wall thickness of 8mm or more, which are commonly known as thick-walled straight seam welded pipes. These pipes have better pressure resistance than thin-walled ones and are generally suitable for high-temperature and high-pressure applications, as well as bridge load-bearing steel structures.

The control measures for thick-walled straight seam welded pipes include: strengthening pre-production inspections of straight seam welded pipes and post-production casting quality; and improving the cleanliness of molten steel in thick-walled straight seam welded pipes through measures such as proper protective ladle tapping.

①Thick-walled straight seam welded pipe manufacturers lower the contact surface temperature between molten iron and carbon bricks to below 1150℃ through cooling, allowing the molten iron to form a thin iron skin layer on the carbon brick surface to isolate the contact between the molten iron and carbon bricks. This not only forms an iron skin layer but also creates a slag layer for protection. This approach utilizes full carbon micro-porous, even ultra-micro-porous carbon bricks, and strives to enhance their thermal conductivity to lower the surface temperature to below 1150℃.

② Use ceramic brick lining to isolate contact between iron water and carbon bricks. Since carbon bricks are difficult to resist iron water erosion, a layer of ceramic bricks is artificially constructed on the surface of the carbon bricks, which is the ceramic cup wall. The ceramic cup is useful only when the carbon brick's resistance to iron water erosion reaches the level of ceramic refractory materials. The welding process of thick-walled straight seam pipes starts from the exit of the heating furnace. After the pipe billet is scaled off by high-pressure water at the exit of the heating furnace, its front end is flash-welded to the tail end of the previous steel billet, which has already entered the rough rolling mill.