How to Control the Welding Deformation of High Frequency Welded Fin Tube?

High frequency welded fin tubes have shown their superiority in many aspects. During the welding process, the deformation needs to be controlled in order to ensure product quality and achieve good heat transfer effects. Usually on the basis of the deformation analysis computer actual measurement of the tube bundle, the use of the program compiled for simulation calculations, and the following measures to control deformation are proposed.

1. Strict control of the quality of the tubes of the HF welded finned tubes and strict management of their straightening process to ensure that the straightness of the tubes is within 1mm/m.

2. Combination of tube box and high-frequency welded finned tubes for matching. Specifically, the initial deflection of the finned tube and tube box is measured one by one and combined with the size and direction of the values to classify the finned tube and the official box in a hierarchical manner. The finned tubes and official boxes will then be assembled according to the deformation pattern of the finned tubes and official boxes during the welding process derived from the simulation calculations.

3. In the process of assembly, a home-made special positioning jig is used to keep the spacing between the high-frequency welded finned tubes basically the same, and then spot welding is used for positioning.

The next step is to use a computer to calculate a suitable welding process, which usually involves welding the weld seam between the HFW finned tube and the official box in two layers, with each row of the weld seam on the official box jumping from the middle to both sides symmetrically, and the four rows of the weld seam on the upper and lower tube boxes being switched symmetrically, with the second layer of the weld seam being welded after the layer has cooled.

In fact, the tube bundle structure is often deformed in many ways after the welding process. One of the deformations that can easily cause quality problems is the flexural deformation, especially of finned tubes. Therefore, in order to improve the quality of high frequency welded finned tubes, measures need to be taken to control the amount of deformation. According to the above improvement measures, it will be possible to further enhance the quality of high frequency welded finned tubes and reduce the deformation.