Dry goods collection, one article explains the application of copper in light industrial production
Abstract: The temperature control function of air conditioners and refrigerators is mainly achieved through the evaporation and condensation of copper tubes in heat exchangers. The size and heat transfer performance of the heat exchange heat transfer tube determine to a large extent the efficiency and miniaturization of the entire air conditioner and refrigeration device. Special-shaped copper tubes with high thermal conductivity are used in these machines. 1. Air conditioners and refrigerators The temperature control function of air conditioners and refrigerators is mainly achieved through the evaporation and condensation of the copper tubes of the heat exchanger. The size and heat transfer performance of the heat exchange heat transfer tube determine to a large extent the efficiency and miniaturization of the entire air conditioner and refrigeration device. Special-shaped copper tubes with high thermal conductivity are used in these machines. Taking advantage of the good processing properties of copper, heat pipes with inner grooves and high fins have recently been developed and produced for use in the manufacture of heat exchangers in air conditioners, refrigerators, waste heat recovery and other devices, enabling the use of new heat exchangers. The total heat transfer coefficient is increased to 2 to 3 times that of ordinary tubes and 1.2 to 1.3 times that of ordinary low-finned tubes. It is currently used in China, which can save 40% of copper and reduce the size of the heat exchanger by 1/3. above. 2. Clocks and clocks Most of the working parts of currently produced clocks, timers and devices with clock mechanisms are made of "clock brass". Copper alloy contains 1.5-2% lead, has good processing properties, and is suitable for mass production. For example, gears are cut out of long extruded brass rods, flat wheels are punched out of strips of corresponding thickness, brass or other copper alloys are used to make engraved clock faces, screws and joints, etc. A large number of cheap watches are made of gunmetal (tin-zinc bronze) or plated with nickel silver (white copper). Some famous bells are made of steel and copper alloys. The hour hand of the British "Big Ben" is made of solid gunmetal rod, and the minute hand is made of 14-foot-long copper tube. A modern watch factory, using copper alloy as the main material, using presses and precise mold processing, can produce 10,000 to 30,000 watches every day at a very low cost. 3. Papermaking Paper seems simple on the surface, but the papermaking process is very complicated. It requires many steps and the application of many machines, including coolers, evaporators, beaters, paper machines, etc. Many of the components, such as various heat exchange tubes, rollers, hammers, semi-liquid pumps and wire mesh, are mostly made of steel alloys. For example, the Fourdrinier paper machine currently used sprays the prepared pulp onto a fast-moving mesh with fine mesh (40-60 mesh). The mesh is woven from brass and phosphor bronze wire. Its width is very large, usually more than 20 feet (6 meters), and it is required to remain completely straight. The mesh moves on a series of small brass or copper rollers, and as it passes with the pulp sprayed on it, the moisture is sucked out from underneath. The mesh vibrates simultaneously to bind the small fibers in the pulp together. Fabric sizes for large paper machines are large, reaching 26 feet 8 inches (8.1 meters) wide and 100 feet (30.5 meters) long. Wet pulp not only contains water, but also contains chemicals used in the papermaking process, which are highly corrosive. In order to ensure the quality of the paper, there are strict requirements for the mesh material. It must not only have high strength and elasticity; it must also be resistant to pulp corrosion, and copper alloy is fully qualified. 4. In printing, copper plates are used for photographic plate making. The surface-polished copper plate is sensitized with photosensitive latex and then photographed on it. The photosensitive copper plate needs to be heated to harden the glue. To avoid softening by heat, copper often contains a small amount of silver or arsenic to increase the softening temperature. The plate is then etched to form a printing surface with a pattern of concave and convex dots. On an automatic typesetting machine, brass font blocks are arranged to create the layout. This is another important use of copper in printing. Type blocks are usually made of leaded brass, sometimes copper or bronze. 5. Brewing Copper plays an important role in the world's beer brewing. Copper was often used for the inner villages of malt barrels and fermentation tanks. In some famous breweries, there are more than ten such large barrels with a capacity of more than 20,000 gallons. In fermentation tanks, in order to cool down, copper pipes are often used for cooling. Copper pipes are also used to pass water vapor for heating when brewing beer, and copper pipes are used to transport wine, etc. When whiskey and other spirits are distilled, copper stills are often used. Whiskey ale needs to be distilled twice, using two large copper stills. 6. In the pharmaceutical industry, various steaming, boiling, and vacuum devices are made of pure copper. Zinc-nickel copper is widely used in medical devices. Copper alloy is also a common material for eyeglass frames.
