Welding and quality control of PVC dipped flexible copper busbar: bending and cracking prevention strategies

 

PVC dipping insulated busbar is made of pure copper or alloy copper as the substrate, and is processed by PVC impregnation to form a flat conductor structure. It has excellent conductivity, thermal conductivity, corrosion resistance, and processability, and is widely used in power transmission, distribution systems, as well as industrial fields such as automobiles and aerospace. In actual production, the Insulated custom copper bus bar with PVC dipping is formed into a hard strip through diffusion welding, which is prone to cracking during subsequent bending processing, seriously affecting product performance and service life. This article focuses on analyzing the causes of such cracking phenomena and proposes targeted prevention and control solutions, providing technical reference for industry production.

 

 

The bending and cracking of PVC dipped flexible copper busbars after diffusion welding into hard rows are mainly caused by four core factors, which need to be closely monitored.

 

One reason is poor welding quality. If the welding process parameters are not properly controlled, hidden cracks are prone to occur at the weld seam, which can significantly reduce the strength and conductivity of the copper bar. Stress concentration during subsequent bending can easily lead to cracking.

 

The second reason is that the copper material is impure. If the impurity content of the substrate is too high, it will increase the brittleness of the material and decrease its toughness. Whether in the welding process or bending processing, it is easy to crack. At the same time, it will also affect the conductivity and thermal core performance of the copper bar and the bonding stability of the PVC dipping layer.

 

Thirdly, the size design of the copper bar is unreasonable. If the size of the hard bar after welding is too large, there will be obvious stress concentration during bending, which exceeds the bearing range of the copper bar, leading to cracking and possible damage to the PVC immersion layer.

 

The fourth issue is improper bending method. If single-sided bending is used, it will cause uneven stress at the bending point of the Plastic dipping copper busbar, with one side experiencing excessive stress and the other side experiencing less stress, leading to internal stress concentration and ultimately resulting in cracking and detachment of the immersion layer.

 

 

Based on the above reasons for cracking and actual production, prevention and control measures can be taken from four aspects to avoid bending cracking and damage to the immersion layer.

 

Firstly, strict control of the welding process is required. As the optimal method for Insulated flexible copper bus bar for power battery pack welding, diffusion welding must strictly follow the process specifications and accurately adjust core parameters such as welding time, pressure, and temperature to ensure that the weld seam is crack free and tightly bonded, while avoiding high temperature damage to the PVC immersion layer, and ensuring welding quality from the source.

 

Secondly, high-quality copper materials should be selected, with priority given to purchasing copper materials with low impurity content and high purity, in order to reduce material brittleness and improve tensile strength; When purchasing, choose formal channels and further optimize the performance of copper materials through pre-treatment processes such as annealing and straightening, laying the foundation for PVC dipping and subsequent bending processing.

 

Thirdly, reasonably control the size of copper bars, optimize the size design of PVC dipped insulated bus bars based on product requirements and bending equipment capabilities; If large-sized products need to be produced, a step-by-step bending method can be used to divide the copper bars into small sections and gradually bend them, reducing stress concentration and protecting the intact immersion layer.

 

Fourthly, adopting a scientific bending method, prioritizing double-sided bending to ensure even force distribution at the bending point and avoid excessive force on one side; Progressive bending can also be used to gradually bend the copper bars, reducing the degree of stress concentration while controlling the bending speed and force to avoid cracking and peeling of the immersion layer caused by improper operation.

 

The quality control of PVC coated bus bars welding and bending processing lies in "source control and process standardization". We need to start with copper material procurement, welding process, and PVC dipping process to avoid basic problems such as impure materials, welding defects, and weak bonding of dipping layers. We also need to design the size of copper bars reasonably, standardize bending operations, and reduce stress concentration. Only by implementing quality control measures at all stages can Busbar isolation be effectively prevented from bending, cracking, and damage to the immersion layer, ensuring the mechanical, electrical, and protective properties of the products and meeting the application needs of various industries. Xiamen Apollo Stamping Welding Technology Co., Ltd's Dip insulated busbar products strictly adhere to the above quality control standards and can be adapted to multiple industry application scenarios.

 

 

If you have any product inquiries, selection and adaptation, or quality control questions related to PVC dipped flexible copper busbars, please feel free to contact Xiamen Ansite at any time. We will provide you with professional product solutions and technical support to help you efficiently implement your project.