Manufacturing Company Summarizes Solutions for Copper Wire Breakage
The significant issue of wire breakage during the production of ultra-fine copper wires is a key technical indicator that has garnered attention in the industry. Resolving the wire breakage problem essentially means achieving successful production of ultra-fine wires. Based on the analysis of wire breakage types and production causes, through extensive industrial practice, process optimization, and equipment improvements, the wire breakage rate has been significantly reduced, enabling the normal production of ultra-fine wires. The measures to address wire breakage primarily include the following aspects.
1. Raw Material - Ensuring Copper Rod Quality
Impurities, pores, and surface damage on copper rods significantly reduce the tensile strength of copper wires. Selecting high-quality raw materials is a prerequisite for the smooth production of ultra-fine wires. In the selection of copper rods, it is crucial to control impurities, pores, and hard defects to ensure the ductility of the copper wire. When producing ultra-fine copper wires, it is advisable to use large-scale enterprises with standard cathode copper as raw material, produced by continuous casting and rolling to ensure the quality of electrical copper rods. These rods have high density, good toughness, and fewer internal and external defects. Additionally, ultra-fine copper wires with diameters below φ0.04mm can utilize some micro-alloyed copper wires to enhance tensile strength, preventing easy breakage during the stretching process.
2. Mold Optimization
Due to the small tensile strength and fragility of ultra-fine wire, it is crucial to minimize resistance during copper wire stretching in the process design. This requires selecting reasonable process dies and mold design while ensuring basic production efficiency. Special attention must be given to the control of die size and geometric shape for micro-drawing wires. The finer the copper wire specification, the smaller the selected reduction ratio. The mold geometric shape follows drawing wire conventions, and as the reduction ratio decreases, the compression angle of the drawing die decreases, while the degree of contact with the wire compression angle remains constant. Additionally, a larger chamfered bell mouth must be present at the entry of the drawing die to prevent scratching during copper wire insertion.
3. Lubricant Selection and Usage
Lubricants can create resistance against the progression of copper wires during the drawing process. When the viscosity of the lubricant is too high, this resistance increases, potentially leading to wire breaks. Lubricants for fine wire drawing typically contain semi-synthetic emulsions, which are diluted from standard copper fine wire lubricants. It is crucial to control the temperature, pH, and concentration of the lubricant to minimize wear on the drawing die and prevent the lubricant from becoming too "sticky" or thick. Otherwise, copper soaps can form on the drawing wheel, increasing drawing resistance and contributing to wire breaks. Regardless of the lubricant chosen, thorough filtration should be conducted during the production process to ensure cleanliness and reduce the accumulation of copper shavings in the drawing die.
4. Equipment Optimization
To minimize additional resistance during the ultra-fine copper wire stretching process, ultra-fine stretching equipment requires high stretching stability and precision in all components. The base and main components such as tower wheels, molds, winding wheels, and gearboxes must possess high rigidity, wear resistance, and proper installation balance, typically treated with chrome plating. Moreover, controlling the stretching stability is crucial, and variable frequency or dual variable frequency models are recommended.
