Classification nan copper bar pwosesis pwosesis ak eksplikasyon kle teknoloji, ki gen ladan continuous extrusion rekòmande pwosesis flow pou pwodwi ultra-mens copper bar bis ducts
Abstract: Electrical copper bar is a high-current conductive copper material. It is used in high and low-voltage electrical appliances, switch contacts, power distribution equipment, bus ducts and other electrical equipment. It is also widely used in metal smelting, electrochemical plating, chemical caustic soda and other ultra-high current smelting. Or electrolysis equipment; the cross-sectional shape is a rectangular cross-section with 4 rounded corners and technical requirements; it has mechanical properties and electrical conductivity properties. 1. Copper bar Electrical copper bar is a high-current conductive copper material. It is used in high and low voltage electrical appliances, switch contacts, distribution equipment, bus ducts and other electrical equipment. It is also widely used in metal smelting, electrochemical plating, chemical caustic soda and other very large Current smelting or electrolysis equipment; the cross-section shape is a rectangular cross-section with 4 rounded corners and technical requirements; it has mechanical properties and electrical conductivity properties. 2. Copper busbar production process The copper busbar production process is mainly divided into two traditional rolling and extrusion processes. The process flow is long, the process is complex, the energy consumption is high, and the material utilization rate is low. A. Large ingot hot-rolled coil billet - high-precision cold rolling method: Large ingot hot-rolled coil billet has mature technology. Hot rolling can fully change the casting structure, but the process flow is long and the equipment investment is large. B. Horizontal continuous casting coil billet - high-precision cold rolling method: Horizontal or upward continuous casting coil billet, short process flow, low equipment investment, residual casting structure after cold rolling, requiring surface milling, resulting in low yield rate. Continuous extrusion process: The new continuous extrusion process technology can combine the advantages of the above two processes. The product has good grain structure (comparable to hot-rolled structure), short process, high yield rate, low investment in equipment and plants, and reduces industry entry. threshold. 3. Advantages of continuous extrusion process: ► Using continuous casting and rolling wire rod as raw material, it is easy to supply, there is no extrusion pressure residue, the material utilization rate is high, generally up to 95%, and the uniformity of structural properties is good. ►Continuous extrusion uses the heat generated by friction to heat up without heating, thus saving energy. ► Fewer processes, high production efficiency and high product yield. ►Can realize continuous production of products without any interval. ►Extra-long products can be produced. Traditional processing methods generally do not exceed 30-50m, while the length of continuous extrusion methods can generally range from several thousand meters to tens of thousands of meters. They are delivered in roll form and are easy to transport. 4. Typical applications of continuous extrusion: ► Refrigeration tube manufacturing ► CATV coaxial cable outer conductor and communication signal cable sheath manufacturing ► Aluminum-clad steel wire manufacturing ► High-speed railway copper alloy contact wire manufacturing ► Copper flat wire and copper bar manufacturing ►Extra-wide row continuous extrusion production of oxygen-free copper rods: The continuous extrusion width is limited, mainly because the maximum width range is 300mm. Key technical issues: how to fill the cavity and how to ensure the uniformity of flow speed during the strip extrusion process. 5. Solution: ► Start exploring from the aspects of billet preheating temperature, setting of mold parameters and reasonable selection of extruder power ► Cavity design ► Mold material and structural properties after cooling and extrusion: ► Material after continuous extrusion The structure is a recrystallized structure, with no plastically formed streamlined structure; ► The structure is uniform and fine, the surface is smooth and flat without oxidation, no surface treatment is required, and subsequent rolling processing can be directly performed; ► The hardness of red copper after extrusion is about HV60-70, It is in a soft state and is suitable for subsequent rolling processing with large deformation. 6. To produce ultra-thin copper bars for busbar ducts, the recommended process flow is: upward → extrusion → rolling → annealing → drawing. The rolling amount of the billet is limited, and the thickness of the rolled semi-finished product is generally greater than 2mm, which can be satisfied by using a two-roll mill. , to avoid wasted functionality. Continuous extrusion manufacturing of hollow cross-section conductive bars (profiles): Hollow cross-section copper bars (profiles) are widely used in electronics, electric power and other fields. The production of multi-hollow heterogeneous cross-section bars is difficult and expensive, and the market is difficult to see. Traditional hollow billet perforation extrusion method: can only produce simple shapes and large sizes (above 50mm in diameter); it is difficult to produce profiles with thin walls, small holes, and long lengths. Traditional - stretching method: mainly produces heterosexual pipes with uniform wall thickness. It is difficult to achieve heterogeneous pipes with uneven wall thickness and is not economical. Internationally leading production technology: wide row continuous extrusion - straight row extrusion, bending first and then straightening, and hollow row continuous extrusion.
