Air Conditioners and Freezers
The temperature control function of air conditioners and refrigerators is mainly realized through the evaporation and condensation of copper tubes in heat exchangers. The size and heat transfer performance of heat exchange heat transfer tubes determine the efficiency and miniaturization of the entire air conditioner and refrigeration device to a large extent. All of these machines are made of special-shaped copper tubes with high thermal conductivity. Utilizing the good processing properties of steel, recently developed and produced heat pipes with inner grooves and high fins, which are used to manufacture heat exchangers in air conditioners, refrigerators, chemical and waste heat collection devices, which can make new heat exchangers The total heat transfer coefficient of the exchanger 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 has been used in China, which can save 40% of copper and reduce the volume of heat exchangers by 1 /3 or more.
clock
Clocks, chronographs and devices with clockwork mechanisms are currently produced, where most of the working parts are made of "horological brass". The alloy contains 1.5-2% lead, has good processability and is suitable for mass production. For example, gears are cut from long extruded brass rods, flat wheels are punched from strips of corresponding thickness, engraved clock faces are made of brass or other copper alloys as well as screws and joints, etc. A large number of inexpensive watches were made of gunmetal (tin-zinc bronze), or nickel-silver plated (nickel-nickel). Some famous bells are made of steel and copper alloys. The hour hand of the British "Big Ben" is a solid gunmetal rod, and the minute hand is a 14-foot-long copper tube.
A modern watch factory uses copper alloy as the main material, processes it with presses and precise molds, and can produce 10,000 to 30,000 watches per day at very low cost.
paper making
In the current information-changing society, paper consumption is huge. Paper looks simple on the surface, but the papermaking process is very complicated. It needs to go through many steps and apply many machines, including coolers, evaporators, beaters, paper machines and so on. Many of these components, such as: various heat exchange tubes, rollers, striking bars, 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 cloth with fine mesh (40-60 mesh). The mesh is woven from brass and phosphor bronze wires. Its width is very large, generally more than 20 feet (6 meters), and it is required to be kept completely straight. The mesh moves over 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 bond the small fibers in the pulp together. Large paper machine fabrics are large in size, up to 26 feet 8 inches (8. l m) wide and 100 feet (3 0.5 m) long. Wet paper pulp not only contains water, but also contains chemicals used in the papermaking process, which are very corrosive. In order to ensure the quality of the paper, the requirements for the mesh material are very strict. Not only must it have high strength and elasticity, but also it must be resistant to pulp corrosion, and copper alloy is fully capable.
to print
In printing, a copper plate is used for photolithography. The surface-polished copper plate is sensitized with photosensitive emulsion, and the image is photographed on it. The photosensitive copper plate needs to be heated to harden the glue. In order to avoid heat softening, copper often contains a small amount of silver or arsenic to increase the softening temperature. Then, the plate is etched to form a printing surface with sub-patterns of concave and convex dots.
On the automatic typesetting machine, the layout of the brass font blocks is used to make the layout, which is another important use of copper in printing. Type blocks are usually leaded brass, sometimes copper or bronze.
brewing
Copper plays an important role in beer brewing around the world. Uchimura, who often uses copper for malt barrels and fermentation tanks. There are more than a dozen such vats with a capacity of more than 20,000 gallons in some famous breweries. In the fermentation tank, in order to cool down, steel pipes are often used for cooling. Also use steel pipes to pass water vapor to heat when brewing beer, and use steel pipes to transport wine liquid and the like.
Steel stills are commonly used when distilling whiskey and other spirits. Whiskey malt is distilled twice, using two large copper stills.
medicine
In the pharmaceutical industry, all kinds of 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 spectacle frames and so on.