High frequency welded finned tube shows its own superiority in many aspects. And in the process of welding treatment, its deformation needs to be controlled to ensure product quality and achieve good heat exchange effect.

In order to control the deformation, the following aspects can be considered:

Welding sequence: Choosing a suitable welding sequence can reduce the possibility of deformation. It is usually recommended to weld from the middle to the ends to ensure that the finned tubes are heated evenly throughout the process, reducing the chance of deformation.

Preheating and Post Heat Treatment: Preheating the workpiece prior to welding slows down the rate of temperature change and helps reduce distortion. Once welding is complete, proper postheat treatment can also help release stresses created during welding and reduce distortion.

Fixtures and supports: Use fixtures and support structures to stabilise the workpiece and prevent it from deforming during the welding process. This can be done by designing the right fixtures to ensure that the workpiece maintains the desired shape.

Control welding parameters: Control welding parameters such as welding current and speed to minimise welding-induced thermal stresses. Ensure that the parameters are selected to suit the material used and the thickness of the workpiece.

Appropriate Welding Method: It is also important to select the appropriate welding method. Sometimes, the choice of different welding methods (e.g. manual, automatic, etc.) can influence the degree of distortion.

Material Selection: Consider using materials with a lower coefficient of thermal expansion to minimise thermal stress and distortion during welding.

Monitoring and Adjustment: Continuously monitor distortion during the welding process and adjust welding parameters or take other measures to ensure that the workpiece maintains the desired shape.

Through comprehensive consideration of the above factors and continuous optimisation in the actual welding operation, the deformation problem during the welding of high-frequency welded finned tubes can be effectively controlled.

Usually on the basis of deformation analysis computer actual measurement of the tube bundle, the use of the programmed simulation calculations, and put forward the following measures to control the deformation:

Measure 1: Strictly control the quality of the tubes of the high frequency welded finned tube and strictly manage the straightening process to ensure that the tube is not straight within 1mm/m.

Measure 2: Selection and combination of tube box and high frequency welded finned tube. Specifically, it is to measure the initial deflection of the finned tube and tube box one by one, and combined with the size and direction of its value, the finned tube and the official box are graded and classified. Afterwards, according to the deformation law of finned tube and official box during welding process derived from simulation calculation, finned tube and official box will be assembled correspondingly.

Measure 3: In the process of assembly, it is necessary to use the homemade special positioning fixture, so that the spacing between the high-frequency welded finned tubes remains basically the same, and then spot welding positioning.

Measure 4: The next step is to use the computer to calculate the welding process for the appropriate method, usually for high-frequency welded finned tube and the official box of the weld in two layers of welding, the official box of each row of welds from the middle to the sides of the symmetrical jump welding, up and down the four rows of welds on the tube box symmetrically switching welding, layer of weld cooling in the second layer of welding after the welding of the weld.

Pipe bundle structure after welding treatment, often produce a variety of deformation. One of the deformations that can easily cause quality problems mainly refers to the flexural deformation, especially the flexural deformation of the finned tube. Therefore, in order to improve the quality of high frequency welded finned tubes, it is necessary to take corresponding measures to control the amount of deformation. According to the above improvement measures, it will be able to further improve the quality of high-frequency welded finned tube and reduce the deformation.