1. Mining and mineral processing: The early American copper production concentrated mainly in the western United States (Arizona, Utah, New Mexico, Montana, and Alaska), when copper production was limited to the mining of rich copper-containing minerals. The introduction of flotation in the late nineteenth century allowed people to extract copper and other metals (including gold and silver) from low-grade porphyry ores. In the mid-1980s, a mining plant introduced a huge, highly efficient transportation system.
2. Flash smelting: Continuously improved electroplating and smelting technologies have successfully increased smelter productivity and productivity, while also increasingly adapting to more stringent environmental constraints.
3. Electrorefining: In the past decade, many refineries have used electrolytic refining instead of conventional starting materials made of stainless steel or titanium. The deposited copper is separated from the stainless steel or titanium starting plate by flexing with a cutter or air jet. Since the automatic processing technology of positive and negative electrodes is introduced in the electrolytic cell, a large amount of labor is also saved.
4. Solvent extraction: Traditional sulphide ore generally needs to be ground, smelted and refined. Solvent extraction requires the processing of low quality oxide ore at a lower price. In the first stage (filtration phase), acidic waste (dilute sulfuric acid) is distributed on a sixty-foot-high mineral heap by swinging platforms, drip irrigation equipment, or sprinklers (Rainbow). When it penetrates, it can Filter out through the dissolved copper heap. The copper-bearing water and the overflowing filtering solution flow out from the bottom of the mineral heap and then into a comprehensive water pool from where it is pumped to the solution refinery. This flooded filter solution is then mixed with a kerosene solution containing an organic chemical that is specifically designed to extract copper. This copper-containing organic material, also called an organic load, is then mixed with a copper-containing sulfuric acid called an electrolyte or an aqueous solution. During the mixing and precipitation process, the copper is converted from the organic solution to the aqueous solution, filtered and then pumped to the electrolysis metallurgy electrolytic cell.
5. Electrolytic metallurgy: During electrowinning, as in the electrorefining process, the copper extracted from the electrolyte is stored for a period of seven days and then placed in a copper negative electrode precursor or stainless steel master. The positive electrode is made of lead. Ten days later, each of the original weighed approximately 1.7 bs (7.7 g of the copper starting tablets had been transformed into copper and weighed 200 bs (90.8 g of negative electrode). The cathodes of the electrolytic copper produced met the requirements of ASTM B115. The specifications for electrolyzed anode copper and electro-deposited copper are all traded in the world's metal trading market.
6. Flow of copper: This shows the entire flow of copper ore or recovered metal swarf until the end market. In the operation of the copper rolling mill, metal alloys such as zinc, lead, tin and nickel have also been introduced. They all comply with ASTM regulations and comply with the legal procedures of the B-2 Committee.
7. Continuous Casting: Perhaps the only important innovation in the copper industry in the past century has been the introduction of continuous wire rod technology from a commercial and technical point of view. Rods produced by this method are the most basic sources of raw materials for the wire and cable industry. Changes in production technology are considerable, resulting in the worldwide replacement of the traditional 250-1b (113.5-kg) wire rods with continuous wire ingot products. Continuous casting allows the coil to weigh up to 10,000-1b (4,540-kg). Before the size of the coil was determined by the 250-1b wire ingot it used, the coil size was only limited by the capacity of the processing equipment. limited. The negative electrode product received by the wire rod factory is basically the same as the part that is continuously cast. Its volume increased from 2.5 million pounds in 1987 to nearly 3.5 million pounds in 1996. Continuous casting steel rods conform to the specifications of ASTM B49, which is the standard specification for hot rolled copper tempered rods used in power. Continuous or semi-continuous casting is also used at the same time to produce a cast block for remanufacturing it into discs, sheets, strips, or to produce a continuous casting block and then sawing it into billets. , to become a transitional product for the production of pipes, pipes and steel rods.
8. Technologically innovative products: More and more manufacturers have transformed their multi-alloy, multi-product production lines into a single product line with a limited number of alloys. For example: pipe products, strip products and rod products, the production of these products are due to processing technology improvements.
9. Analytical control: Both refiners and copper mills benefit from analytical configurations that quickly determine the chemical composition of the molten metal in the holding furnace and control the contents before casting.
10. Seamless steel tubes: Advances in the production of seamless steel tubes for pipelines, refrigeration, medical air, natural gas and liquefied petroleum vapors have made copper a preferred material for use in residential, commercial and industrial buildings. From a historical point of view, the production of seamless copper tubes was first to transform a solid billet into a hollow shell by a piercing process. Extrusion shells with a thin wall thickness were introduced to the market in the 1950s, when large extruders were available, which had higher extrusion speeds. In addition, these housings are also suitable for cold drawing on cold drawing machines and cold drawing on a larger unit weight roller box type drawing drum on cold drawing tables than in the past. One of the major advances in the design of cold drawing machines is the widespread use of rotators or continuums in pipe removal. This principle has evolved from the wire industry. The high-speed merging machine cleans, straightens, inspects, marks and cuts the pipe according to a certain size, and then transfers the product to the tying device according to a strict size, or rewinds the product. The purpose is to use the cord. Can be annealed. The irregular pipe wall thickness in ASTM B88 and the specification of seamless copper pipes turned to 0% a few years ago. People are now re-examining it on the basis of in-depth engineering assessments. Seamless pipes for air conditioning applications are increasingly being produced through the Schumag program, during which a carbonized float is required for a straight pass. This procedure uses a high degree of attention to improve the control of the wall thickness. Pipes used for medical and natural gas or LP steam applications require high internal surface cleanliness. This requirement is achieved by immersing the tube in an appropriate chemical cleaning machine and then testing the tubular product by the procedure in the regulations of B 819. These regulations are specific to medical air seamless copper tubes, B837 , seamless copper tubes for natural gas and liquefied petroleum gas fuel distribution systems.
11. Welded pipes: In the 1960s, soldered copper and copper alloys produced with copper instead of filler metals became quite commercialized. The copper strips in the expenditure coil were consolidated in the next few steps. The shape of the tube is then welded using one of several alternative methods. Its main specifications are: ASTM 447, welded copper tubes and ASTM B 543, and copper and copper alloy heat exchange tubes. The main advantages are: There is an opportunity to Utilizing extra copper strip capacity, it is possible to produce selective pipe lengths without any metal waste, producing long coils suitable for cooling and air conditioning, as well as other uses in gasoline and oil production lines. Tight pipe wall thickness is another advantage. In residential houses, the application of welded brass pipes in the laying of pipes, sewer pipes, construction and in the production of headboards, footboards and lampposts shows a slow and steady increase.
12. Enhanced pipe surface: The modified ASTM B 359 specification, instant specification for copper and copper alloy seamless condenser and heat exchanger pipes with integrated heat sinks, is specifically for advanced surface condensers and other specialty The air-conditioning equipment was designed and manufactured. A similar specification for the application of welded pipe plates is also in the making. Such pipe has its own inner surface or outer surface, or both, to produce a whole by a cold forming method. An enhanced surface is obtained, thereby improving the heat transfer associated with the nucleic acid salt. According to the Monroe agreement of 1995, this development is actually driven by the denial of worldwide production of specific olfactory oxygen layers such as R11 and R12. The refrigerants used for substitution are R134 and R123. Although they show no destructive behavior, they are not very thermodynamically effective; therefore, we need pipes with higher heat exchange characteristics.
13. Discs, Sheets, and Strips: These products originally appeared as direct, chilled, cast blocks whose size increased from the very first 7,000 lbs to the current 55,000 lbs (3,200 kg to 25,000 kg). Due to the production of large coils, both the quality of the metal and the production efficiency have been improved. Precise setting of the copper strip width limit, free edge setting, and other improvements have been basically standardized. There is also a strip annealing furnace which has been introduced into the production operation process. It can provide advanced particle size control, reduce the demand, and save the area of ​​the plant compared with the conventional bell-type annealing furnace. In the domestic production plants, the rolling process has largely replaced the pull-out process, thereby improving product quality and production efficiency. During World War II, the U.S. copper industry made a less well-known contribution to the Manhattan project. In Tenn, Oak Ridge, a copper busbar is very urgently needed in the uranium 235 refining facility. Because all copper is used for warfare, this requires a material with similar conductivity. (Silver's conductivity is 104% IACS, while copper's chargeability is 100% IACS, so silver is a fairly suitable alternative.) There are about 700 million troy ounces of pure copper (equivalent to today's ASTM B413, which is a regulation of refined silver, was borrowed from the U.S. Department of the Treasury and shipped to U.S. Metal Refining Company (USMR) in NJCarteret, where it was re-melted and then cast into pure silver wire ingots. These wire ingots are then transported to Phelps Dodge;s Elizabeth, located in NJ, and these devices are rolled into busbars (equivalent to today's ASTM B187 regulations for copper rods, buses, and rods). In the late 1970s, silver busbars were removed from service projects, transferred back to the USMR for melting, refining, and casting into ingots weighing 1,000 troy ounces and returned to the Ministry of Finance.
14. Copper rods: The brass and brass rod industries produced nearly 1.1 million pounds of brass rods and brass rods in 1996, and this industry has now introduced a semi-continuous type of large-scale mass extrusion ingots. The casting method also increased the capacity of the extruder from 2,000 tons to 6,000 tons. This eliminates the drawbacks of the extrusion process and allows large-scale coils to be produced with higher production efficiency, and the increase in production efficiency, if combined with improved correction equipment, can be produced for multi-axis applications. More advanced products used in screw machines.
15. Copper wire: Natural diamonds used for die casting have largely been replaced by polycrystalline artificial diamonds. The continuously enhanced die design improves the surface condition by greatly reducing surface oxides, while also achieving higher mechanical properties. Multi-wire drawing machines are now very common and are also equipped with advanced insulating paints, making them suitable for high-temperature conductive applications. In magnet wire applications, the size of the motor can also be reduced because its temperature capability has been improved.
16. Main Markets: A wide variety of copper alloys are present in myriad applications where they have become the material of choice for merchants with their unique characteristics. Here are some of the main market uses introduced:
1) Residential and other line products: The residential line is the largest copper consumer market in the United States. In 1997, the use of copper was about 1.4 billion 1bs, which accounted for 16.9% of all copper metal shipped. In the cable industry, the second largest copper market is magnetic wire, which is about 700 million 1bs. It is mainly used for motors, generators and transformers and accounts for about 18% of all copper products shipped. A relatively small but very desirable application of copper is in the field of power cables.
2) Automotive power: In 1997, the consumption of automotive wires and cables was 300 million 1bs. The modern bus power system is very complex and consists of various parts, cables and terminals. This reflects the enhancements in power, lighting, control equipment, entertainment facilities and all other convenience facilities that are expected in modern cars and light trucks. At the same time, several new alloys have also been developed for the application of temperature standards, such as catalytic converters.
3) Computers: Recently, copper alloy C66300 (only nominally 86% copper, 2.2% tin, 2% cobalt, and the remainder zinc) has been successfully used in the computer industry to produce a leadframe. Connector.
4) Pipeline system: In the three pipe wall thickness plans already established, copper pipes are still a major factor in engineering construction. In 1997, the copper used for laying pipelines was 652 million 1bs, accounting for 18.9% of the total copper shipped in the United States. Its main specification is B88, a seamless copper water pipe.
5) Air Conditioning and Refrigeration: Copper's outstanding anti-corrosion and heat exchange characteristics have made copper applications in the refrigeration field growing, especially in the "sun belt countries." Population and industrial development are directly linked to refrigeration equipment. To a large extent, this is achieved through the use of copper in its equipment. Imagine the entire process from the air-conditioned house to the car to the shopping mall and finally to the production facility. Its main specifications are: B280, a seamless copper tube for air conditioning and refrigeration base service companies.
6) Car Radiator: Although the market share of automotive radiators has been surpassed by aluminum, it is still the single largest brass strip market in the United States. ASTM B 569, a specification for narrow and light brass strips for heat exchanger tubes, has been used to meet the production needs of thin walled water pipelines for heat exchangers in internal combustion engines and other closed system heat sources. 7).Coins: In the past fifteen years, the Canadian government once withdrew the issuance of one dollar and two dollar bills, replaced by copper metal coins, often called "Loonies" and "Toonies". (This name is used to represent the image of a loon on the back of a dollar coin.) In February 1998, the American Coin Federation met with representatives of the U.S. Department of the Treasury and the U.S. Mint, and reviewed the technical history of the one dollar coin together. . This coin is expected to be made of a copper alloy and started casting in 2000 as part of public international law. This law stipulates that the diameter of this new coin must be the same as the diameter of the current Susan B. Anthony coin, its color must be gold, and its edges should be conspicuous, and coins and their parts (including bar and block products) must be produced in the United States. . The design and safety requirements, that is, the unique electromagnetic signatures of automatic currency recognition machines, are also very important. The mint carefully examined two gold-plated metal systems - one was a gold Nordic coin (similar to the Swedish krona) and the other was a modified British pound. The acceptance of new coins in public and commercial settings will ultimately determine whether old notes will be cancelled.
8) Copper Roofing: In the United States, the use of copper and copper strips as roofing materials has been on the rise in the past few decades. The ASTM B 370 specification, the construction of copper strips and copper blocks, has become the basis for specifications and purchases in a variety of models and thicknesses. The competitive quantity of copper metal and confidence in copper continue to drive the development of this healthy market. The most recently approved specification is ASTM B882, a pre-rusted copper used in construction. Architects and engineers have long expected production to use this product because they are eager to develop this commendable green with copper roofs and crossbars.
9) Low-lead and lead-free forged and cast copper alloys: The impact of lead leachate into water on human health has led to a rethinking of existing copper alloys and the development of a new alloy for drinking water. The pressure tightness of castings and the superior machinability of forged and cast parts provided by lead appendages are all requirements that must be met. Forged and cast lead-free crucibles containing alloys must have the following characteristics: Meet ANSI/NSF 61 health requirements and component water system health requirements. Nowadays, people have begun to remove lead stains on the machine with an acidified sodium acetate detergent. However, certain sectors of the industry have raised concerns about mixed swarf because they believe that a small amount of niobium in these mixed swarf will cause the metal's hot brittleness during processing. ISRI and Brass and Bronze Casting Manufacturers (BBIM) are working on a strict control program and segmentation procedures for scrap recycling.
10). Household products: In household products, people choose copper because copper has the following characteristics: beautiful shape, reliable quality, high goodwill, good design factors, better material and mechanical properties to longer The service life. Electric lighting fixtures and stove equipment have become major household product categories. 11) Service: The traditional method for determining the sensitivity of copper raw materials to stress corrosion cracking is the mercury nitrite test. (ASTM B154) In response to requests from the ASME Boiler and Pressure Vessel Code and the US Coast Guard, the B-5 Commission converted the stress corrosion-immune IS0 6957 copper alloy ammonia test to ASTM form. This is entirely due to their consideration of test solutions and sample handling. ASTM B858M, a method of using ammonia vapor in copper alloys to determine its sensitivity to stress corrosion cracking, is now an officially used method. This test method stimulates the development of service conditions under which stress corrosion cracking may occur and overcome the disadvantages of the mercury nitrite test.
12) Future Outlook: The world economy is becoming more and more global. With the advent of the 21st century, third-world countries are establishing telecommunication links, becoming the main consumers of electricity. They are building homes, factories and commercial buildings, which require large amounts of copper to meet their needs. Copper has been used as a raw material for engineering for 10,000 years. Its contribution to human beings is pyramidal and growing. Without copper, I can't imagine what the future world will look like.