What are the core values of photovoltaic welding strip rolling mill

       The photovoltaic welding strip rolling mill is the core equipment for photovoltaic welding strip production, and its core value runs through the four core dimensions of welding strip quality, component performance, production efficiency, and industry adaptability. It directly determines whether the welding strip can meet the strict requirements of photovoltaic modules (especially high-efficiency modules), and is also the key to cost reduction and efficiency improvement of the production line. The core value can be summarized as 5 cores+2 extensions, accurately landing and meeting the industry's needs:

       1、 Core Value 1: Precision of fixed welding strips to ensure component power generation efficiency (the most essential requirement)

       The dimensional accuracy of photovoltaic ribbon directly affects the bonding degree and current conduction efficiency of battery cell string welding. The rolling mill is the "first and most critical line of defense" for accuracy, which is the foundation of its core value

       Control micrometer level dimensional tolerance: When rolling oxygen free copper wire into flat strips, the thickness tolerance can be accurately controlled within ± 0.005~0.015mm, and the width tolerance can be ± 0.02mm, completely eliminating the problem of uneven thickness and width of the welding strip; The uniform size of the welding strip is necessary to accurately adhere to the grid lines of the solar cells, reduce welding gaps, lower contact resistance, avoid current loss, and directly improve the power generation and consistency of the photovoltaic modules.

       Strictly control surface quality: After rolling, the surface roughness Ra of the welded strip is ≤ 0.1 μ m, without scratches, burrs, or oxidation spots, laying the foundation for subsequent tin plating processes; A clean and smooth surface can prevent pinholes, tin slag, and detachment of the tin plating layer, ensuring the conductivity and welding firmness of the solder strip, and preventing power attenuation caused by virtual soldering and broken soldering during long-term use of the component.

       Ensure cross-sectional regularity: The welded strip formed by rolling has a standard flat cross-section, without warping or twisting, and can be uniformly stressed during series welding, fitting closely to the surface of the battery cell, reducing the risk of hidden cracks, while ensuring uniform current conduction and improving component reliability.

2、 Core Value 2: Adapt to efficient photovoltaic modules and keep up with industry technological iterations (core competitiveness)

       The current photovoltaic industry is upgrading to high-efficiency components such as HJT, TOPCon, IBC, etc., with stricter requirements for welding strips. The adaptability of the photovoltaic welding strip rolling mill directly determines whether the production line can keep up with the industry trend and not be eliminated

       Adapting to the production of ultra-thin and ultra-fine welding strips: Efficient components require welding strips to be thinner (0.05~0.15mm) and narrower (0.5~2mm), which are difficult to control with ordinary rolling mills. Photovoltaic special rolling mills can stably produce such ultra-thin and ultra-fine welding strips through precision roller systems and servo closed-loop control, adapting to the serial welding requirements of fine grid battery cells, reducing the shading area of welding strips, and improving the light receiving efficiency of components.

       Suitable for special welding strip substrates: Supports oxygen free copper and copper alloy (such as copper silver, copper tin alloy) wire rolling. These special substrate welding strips have stronger conductivity and better weather resistance, and are suitable for HJT low-temperature welding and TOPCon high-power component requirements. The rolling mill can ensure that special materials do not deform and their performance does not deteriorate during rolling.

       Compatible with multiple specifications and quick changeover: It is compatible with incoming wire with a diameter of 0.1~3mm, rolling full specification welding strips with a width of 0.5~8mm and a thickness of 0.05~0.5mm. During changeover, only parameters and a small number of rolling mill accessories need to be adjusted, without the need for significant equipment modification. It is suitable for multiple varieties, small or large batch production, and meets the market's demand for welding strips of different components.

3、 Core Value 3: Reduce costs and increase efficiency, improve overall production line efficiency (essential core)

       Reducing costs and increasing efficiency is an eternal theme in the photovoltaic industry. Rolling mills optimize processes and improve utilization rates to reduce welding strip production costs from the source and enhance production line competitiveness

       Improving material utilization: Adopting multi pass continuous rolling and closed-loop control to reduce losses during wire rolling (loss rate ≤ 1%), reducing losses by more than 30% compared to ordinary rolling mills; At the same time, there is no need for additional cutting or correction processes, maximizing the use of oxygen free copper raw materials and reducing raw material costs (copper materials account for more than 70% of welding strip costs).

       Realize high-speed and stable mass production: The rolling speed can reach 60~200m/min, and the daily production capacity of a single line is 350~460kg, far exceeding that of ordinary rolling mills; And the entire process is automated and continuous, without the need for manual intervention in intermediate links, improving production efficiency and reducing labor costs.

       Reduce subsequent process costs: After rolling, the welding strip size is precise and the surface is clean. There is no need for additional grinding or correction during subsequent tin plating, reducing the amount of tin plating materials (such as uniform tin layer thickness, saving tin materials), while reducing the defect rate, minimizing rework losses, and further reducing overall production costs.

4、 Core Value 4: Ensuring the mechanical performance of welding strips and improving the service life of components (implicit core value)

       Photovoltaic modules require outdoor service for more than 25 years, and the mechanical properties of the welding strip are crucial. The rolling mill optimizes the process to ensure that the welding strip has both conductivity and weather resistance

       Controllable rolling stress and improved flexibility: The rolling mill integrates an online annealing module, which can eliminate the internal stress of the copper strip in real time during the rolling process, soften the base material of the welding strip, and make the welding strip have both high strength and good flexibility, avoiding the breakage of the component due to the brittleness of the welding strip in outdoor hot and cold alternation, wind and sun exposure.

       Ensure stable conductivity: During the rolling process, the conductivity of the copper material is not damaged (conductivity ≥ 98% IACS). At the same time, precise temperature control is used to avoid copper strip oxidation, ensuring that the conductivity of the solder strip does not deteriorate during long-term use and guaranteeing stable power throughout the 25 year service life of the component.

       Improving weather resistance foundation: After rolling, the surface of the welding strip substrate is dense, without micro cracks, and the subsequent tin plating layer has stronger adhesion, which can better resist harsh environments such as outdoor salt spray, ultraviolet radiation, high temperature and humidity, reduce welding strip corrosion and aging, and extend the service life of components.

5、 Core Value 5: Automation and Intelligence, Ensuring Production Stability and Compliance (Basic Core Value)

      The production of photovoltaic welding strips requires extremely high stability and consistency. The automated and intelligent design of the rolling mill fundamentally ensures production stability and reduces management costs

      Full process closed-loop control, stable full: adopting PLC+servo closed-loop control, real-time monitoring of rolling thickness, width, tension, deviation automatic compensation (response ≤ 0.01s), 24-hour continuous production without fluctuations, defect rate ≤ 0.3%, far lower than the defect rate under manual control.

      Intelligent monitoring and warning: Equipped with online detection and fault warning functions, it can display rolling parameters and size data in real time, automatically stop the machine in case of abnormalities, and avoid the production of batches of defective products; Simultaneously recording production data for easy traceability, in compliance with the regulatory management requirements of the photovoltaic industry.

      Reduce operational barriers and maintenance costs: modular design, key components (rollers, bearings) are easy to disassemble and maintain, and daily maintenance does not require professional tools; The operation interface is simple, requiring only 1-2 people to be on duty, without the need for professional technicians, reducing labor and maintenance costs.

6、 Two major extended values (adding icing on the cake and enhancing production line competitiveness)

      Green and environmentally friendly production: supporting waterless rolling technology, reducing wastewater discharge by more than 90%; Online annealing adopts an energy-saving temperature control system, which saves 20% to 30% energy compared to traditional annealing and meets the policy requirements for green production in the photovoltaic industry.

      Strong adaptability of whole line integration: It can seamlessly connect with subsequent tin plating machines, slitting    machines, and winding machines to form a fully automated production line for photovoltaic welding strips, reducing intermediate transportation links and further improving production efficiency, achieving integrated production from copper wire to finished welding strips.