Principle and working method of seam welding machine

During seam formation (intermittent seam welding), each weld point is also preloaded, energized, and cooled. However, due to the changing relative position of the roller electrodes during the weld, the three stages of the weld are not distinguishable and can be achieved with linear roller electrodes: 1) The heated metal is electrically charged, thus inducing heat in the metal. This is the "energized heating phase." 2) Adjacent metal enters the roller electrode and is received by the roller electrode, entering the "preload phase." 3) On the other hand, the adjacent metal beneath the roller electrode begins to cool, while the voltage of the roller electrode divides the metal, still in the "cooling crystallization phase." Therefore, the weld area beneath the roller electrode and the adjacent metal materials on the adjacent sides are simultaneously in different stages. For any weld point in the weld, the roller process is a three-stage process of "preload-energized heat-cooling crystallization." Because this process is performed dynamically, the pressure during the preload and cooling crystallization phases is not sufficient, resulting in consistently high weld quality and the removal of cracks, shrinkage, and defects.

Seam welder operating methods

Based on wheel electrode rotation (welding) and welding current (energization), they can be categorized into three stages.

Continuous Seam Welding

The roller electrode rotates continuously, creating a uniform weld. The welding current flows continuously, and each semi-rotational joint forms a weld. Welding speeds can reach up to 10 to 20 m/min. However, due to poor weld surface finish, its practical application is limited.

Intermittent Seam Welding

The weld moves continuously, with the welding current flowing, and each "interruption" forms a weld spot. Depending on the thickness, welding speeds can reach 0.5 to 4.3 m/min. It is widely used, primarily for welding ferrous metals using gas, water, or oil seals.

Step Seam Welding

During welding, the welding current flows in increments, creating each "interruption" and allowing the weld spot to be applied. Joint formation is very similar to spot welding, but welding speeds are lower, typically only 0.2 to 0.6 m/min. It is only used to produce high-film welds such as aluminum and magnesium alloys.