Different welding methods have a significant impact on the quality and performance of LSAW (straight seam submerged arc welding) steel pipes. The following are several common welding methods and their specific effects on LSAW Steel Pipes:

Submerged arc welding

Weld quality: welding is carried out under the flux layer, the slag has a good protection effect on the molten pool, the weld metal is not easily affected by external factors such as air, there are few impurities, the toughness, plasticity, uniformity and density of the weld are good, and the strength and sealing of the weld can be effectively guaranteed. It is suitable for LSAW steel pipes with high requirements for weld quality, such as oil and gas pipelines.

Production efficiency: The welding current is large, the welding wire is continuously fed, the welding speed is fast, and automated welding can be realized. A large amount of welding work can be completed in a short time, which is suitable for large-scale production of LSAW steel pipes.

Welding deformation: Since the heat is concentrated and stable during welding, the heat-affected zone is relatively narrow, so the welding deformation is relatively small, which helps to ensure the dimensional accuracy and shape tolerance of LSAW steel pipes.

Scope of application: Suitable for welding medium and thick plates. LSAW steel pipes usually use medium and thick plates as raw materials. Submerged arc welding can well meet its welding needs. It can weld LSAW steel pipes of various materials such as carbon steel and alloy steel.

Gas shielded welding (MAG, etc.)

Weld quality: Using gas as a protective medium can effectively prevent air from polluting the molten pool. The weld surface is smooth and the shape is beautiful. It can reduce defects such as pores and slag inclusions in the weld. It is more suitable for some LSAW steel pipes with high requirements for weld appearance quality.

Production efficiency: The welding speed is fast, especially when performing thin plate welding or base welding, the welding operation can be completed quickly. It can be applied in the pre-welding of LSAW steel pipes and other links, which can provide a good foundation for subsequent welding processes and improve overall production efficiency.

Welding deformation: The heat is concentrated, the heat-affected zone is small, and the welding deformation is relatively small, which is conducive to controlling the deformation of LSAW steel pipes, especially when welding some thin-walled or LSAW steel pipes with strict deformation requirements.

Scope of application: LSAW steel pipes of various metal materials can be welded, including carbon steel, stainless steel, aluminum alloy, etc. It has strong adaptability to different materials and can be welded in different spatial positions, with high flexibility.

Manual arc welding

Weld quality: The welding quality depends largely on the welder's operating skills and experience, and the quality stability is poor. When welding LSAW steel pipes, defects such as uneven weld width, uneven excess height, pores or slag inclusions may occur, making it difficult to ensure the consistency and reliability of the weld.

Production efficiency: Manual operation, slow welding speed, low production efficiency, not suitable for large-scale industrial production of LSAW steel pipes, only suitable for welding work in small batches, emergency repairs or special locations.

Welding deformation: Due to the instability of the welder's operation, the heat input during welding is uneven, which can easily lead to large welding deformation, which will have a great impact on the dimensional accuracy and straightness of the LSAW steel pipe.

Scope of application: The equipment is simple and the cost is low. It is suitable for welding of LSAW steel pipes with low requirements on welding quality, small pipe diameter or limited on-site conditions, such as repair of small pipelines.

Electroslag welding

Weld quality: During the welding process, the molten pool exists for a long time, the metallurgical reaction is sufficient, the chemical composition of the weld metal is uniform, the structure is dense, and the weld quality is good. It can be used to weld thick-walled LSAW steel pipes, which can ensure the strength and toughness of the weld.

Production efficiency: The welding speed is fast. For the welding of thick plates, the thickness of one welding is large, which can reduce the number of welding layers, thereby improving production efficiency. It has certain advantages in the production of large-diameter and thick-walled LSAW steel pipes.

Welding deformation: The heat distribution is uniform, the welding heat-affected zone is narrow, and the welding deformation is small, which is conducive to ensuring the dimensional accuracy and appearance quality of the LSAW steel pipe, especially for large and thick-walled LSAW steel pipe structures, which can effectively control deformation.

Scope of application: It is mainly suitable for welding in a vertical position. For the longitudinal seam welding of LSAW steel pipes, if electroslag welding is used, the particularity of its equipment and process needs to be considered. It is suitable for LSAW steel pipe welding under specific structures and production conditions.

Submerged arc welding has become the preferred welding method in the production of LSAW steel pipes due to its stable quality, high production efficiency and good weld performance. Although other welding methods have advantages in certain specific scenarios, they are usually not the first choice in the production of LSAW steel pipes. Therefore, when choosing a welding method, comprehensive consideration should be given to the specific application scenarios and requirements.