Steel pipe submerged arc welding in one step

The characteristics of submerged arc welded steel pipes are: the production process of straight seam welded steel pipes is simple, high production efficiency, low cost, and fast development speed. The strength of spiral welded pipes is generally higher than that of straight seam welded pipes. Welded pipes with larger diameters can use narrower billets. Production, submerged arc welded steel pipe: It is a spiral welded pipe made of strip steel coil plate as raw material, often using warm extrusion molding and automatic double-line double-sided submerged arc welding process. Welded pipes of different diameters can produce billets of the same width. Let me introduce to you what submerged arc welding of steel pipes is like?

The submerged arc welding process is ideal in important applications such as pipelines, pressure vessels and tanks, railway manufacturing and large construction. It has the simplest form of single wire, double wire structure, series double wire structure and multi-wire structure.
From increasing productivity to improving the work environment to ensuring consistent quality, the submerged arc welding process can benefit users in many welding applications. Metal fabricators who are considering making changes to their submerged arc welding process should consider the many benefits that can be derived from this process.
Basic knowledge of submerged arc welding
The submerged arc welding process is used in heavy industrial applications such as pipes, pressure vessels and tanks, locomotive manufacturing, and heavy construction/excavation. It is ideal for industries that require high productivity, especially for very thick material welding industries, and can gain many benefits from the submerged arc welding process. Its high deposition rate and travel speed can have a significant impact on worker productivity, efficiency and production costs, which is also one of the main advantages of submerged arc welding. Other benefits include: excellent chemical composition and mechanical properties of the weld, minimal arc visibility and lower welding fumes, improved comfort in the work environment and good weld shape.
Submerged arc welding is a wire feed mechanism that uses granular flux to separate the arc from the air. As the name suggests, the arc is buried in the flux, which means that after setting the parameters, a layer of flux flows out. The arc heating melts part of the welding wire, part of the flux and the base metal to form a molten pool, which condenses and is covered with a layer of welding slag. The thickness of the welding material ranges from 1/16 -3/4, and 100% penetration welding can be achieved through single pass welding. If the wall thickness is not limited, it can be welded multiple times and appropriate pretreatment methods should be selected. Choose the right wire and flux combination.
Flux and wire selection
Choosing the correct flux and wire for a specific submerged arc welding process is critical to obtaining the best results using that process. Although the submerged arc welding process alone is effective, it can even increase productivity and productivity based on the wire and flux used. efficiency. Flux not only protects the weld pool, but also helps improve the mechanical properties and productivity of the weld. Flux formulation has a large impact on these factors, affecting current carrying capacity and slag release. Current carrying capacity refers to maximum deposition efficiency and high quality welding profiles. The slag release of a particular flux can influence flux selection, as some fluxes are better suited to certain welding designs than others.
Flux selection options for submerged arc welding include active and neutral welding. A basic difference is that active flux changes the chemistry of the weld, while neutral flux does not. Active fluxes are characterized by silicon and manganese. These elements help maintain the tensile strength of the weld at higher heat inputs, help keep the weld smooth and smooth at higher travel speeds, and provide good slagging capabilities. Typically, active flux helps reduce the risk of poor solder quality and costly post-solder cleaning and rework. Keep in mind, however, that active fluxes are generally best for single- or two-pass welds, and neutral fluxes are better for larger multi-pass welds because they help avoid the formation of brittle, crack-sensitive welds.
There are many choices for submerged arc welding wire, each with their own pros and cons. Some wires are formulated to weld at higher heat inputs, while other wires are specifically designed with alloys that aid in soldering cleaning by the flux. Note that the interaction between the chemical properties of the welding wire and the heat input affects the mechanical properties of the weld, and productivity can also be greatly improved through filler metal selection. For example, using metal-cored wire with a submerged arc welding process can increase deposition efficiency by 15% to 30% compared to using solid wire, while also providing a wider and shallower penetration distribution. Due to its high travel speed, metal-cored wire also reduces heat input to minimize the risk of weld distortion and burn-through.