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Quality control items in the welding of longitudinally welded pipes

Only by controlling the quality of longitudinally welded pipes can production operations be carried out safely, which is also an inevitable element to ensure the personal safety of operators. The application fields are mainly in large-span grid engineering, construction steel structure engineering, electric power and ultra-high voltage transmission and distribution engineering, mechanical engineering, cross-sea bridges, bridges, (railroad station, airport, stadium steel structure engineering), municipal pipeline network, Supporting facilities such as foundation piling, water gas pipeline and road construction.



So what are the precautions for quality control during the welding process?

1. Check whether the specifications of the welding wire and flux are correct according to the welding procedure regulations to prevent the wrong use of welding wire and flux and cause welding quality accidents.


2. Supervise the welding environment. When the welding environment is not good (the temperature is lower than 0℃, the relative humidity is greater than 90%), corresponding measures should be taken before welding.


3. Before pre-welding, check the groove dimensions, including gaps, blunt edges, angles and misalignments, whether they meet the process requirements.


4. Whether the welding current, welding voltage, welding speed and other process parameters selected in the automatic submerged arc welding process are correct.


5. Supervise the welding personnel to make full use of the length of the pilot arc plate at the end of the steel pipe during automatic submerged arc internal and external welding, and strengthen the use efficiency of the pilot arc plate during internal and external welding, which helps to improve the quality of pipe end welding.


6. Supervise whether the welding personnel first clean up the slag when repairing welding, whether the joints have been thoroughly treated, whether there is oil, rust, slag, water, paint and other dirt at the groove
 

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