Milan6063 aluminum tubeDisputes in the field of trade

announcer:hp535HP136858825 release time:2024-01-07 09:48:08

For the production and processing of sculpted copper tubes, the sheet metal shall be first opened in the sheet metal workshop according to the dimensions shown in the drawings, which is commonly referred to as opening. Then cut the corners of these open sheets according to the height of the edge, and then use the bending machine to form the edge according to the drawing forming diagram. The shaped copper pipe shall also be installed with reinforcing ribs as required, and the four corners of the shaped plate shall be welded well. The welded parts shall be sent to the grinding workshop, and the spraying surface shall be polished and the welding interface shall be polished and leveled. The polished modeling copper pipe is then sent to the spraying workshop for processing. Before spraying the surface of the sculpted copper pipe shall be chrome treated and the process hole shall be drilled, so as to ensure that the sculpted copper pipe can be hung on the spraying line well, and the painting can be smooth without flow marks, and the color is consistent without color difference. After that, according to customer demand, the qualified products are pasted with protective film and bound with bubble film or wooden box.

Pay attention to the following points when using flame heating brazing: the selection of welding materials The filler metal is wire or rod, with a diameter of about 35mm. The material is: the melting temperature of wire 221 is about 0905 ℃. Its chemical composition is FB10 The composition is 2331% H3BO3 and 6071% KBF The joint form of brazed copper pipe is mostly plug-in. Before cleaning the brazed copper pipe before welding, the edge of the pipe mouth must be corrected and deburred to ensure that the pipe mouth is free of cracks or other defects. And clean the surface of the inserted part. After the red copper pipe is assembled by tack welding, it shall be fixed by tack welding. The number, size and height of tack welds shall be symmetrically and evenly distributed along the circumference from top to bottom, left to right, and the tack welds shall be melted into the whole weld during brazing. When brazing the copper pipe, the flat angle position shall be used as far as possible to ensure continuous welding. Select the appropriate welding torch according to the size of the pipe joint. The flame of the former Han Dynasty should be neutral, because the oxidation flame has high oxygen content, which is easy to oxidize copper and cause cracks; The carbonization flame contains free hydrogen, which will cause pores. When heating pipes before welding, the flame shall be perpendicular to the heating surface, the pipe joints shall be heated evenly, and the base metal shall be heated as quickly as possible to avoid excessive temperature and heating time of the through pipe joints. During the brazing of degreased copper tube, the brazing seam and filler metal shall be under the protection of flame. In addition, it shall be noted that the brazing seam shall be naturally cooled after welding, and the weldment shall not be moved before the brazing seam has solidified. After natural cooling after welding, hot water or wet cloth shall be used to wipe the brazing seam and remove welding slag to improve corrosion resistance and reliability of post welding inspection.

Milan.The price of pig iron market rose by 50-170 yuan this week, and the transaction was fair. With the increase of coke price, the cost of ductile iron in Shanxi, Henan, Liaoning, Shandong and other regions has increased. In addition, with the gradual release of downstream demand, the inventory of iron plants is not large, and iron plants have successively raised their prices. There are few iron foundries in Shandong, Jiangsu, Hebei and Shanxi, and the inventory remains low. As the coke price rises and the cost increases the price of iron foundries rises again.

When cutting the copper pipe of air conditioner, use tools such as clamps to fix the copper bar and then cut it, rather than fixing it by hand, to prevent shaking and resulting in irregular cutting. 3 After the cutting of the air conditioner copper pipe is completed, the cut parts need to be placed in a dry place, and then processed again after cooling, otherwise oxidation will occur due to high temperature. Liu Shuchen, director of the Resource Analysis Office of the Information Center of the Ministry of Land and Resources, said that copper bar manufacturers are currently in a period of adjustment in China's mining industry as a whole. In the long run, the mining super cycle driven by China's demand has not changed, the global mining industry will rise again, and the W-shaped trend will fully emerge. In the second half of the year, there were signs of stabilizing and rebounding. In terms of the macro factors affecting the bulk commodities, the factors affecting the European market of tinned copper bars have gradually weakened, and the economic conditions of China and the United States have become the key factors affecting the bulk commodities. The European economic recession is a foregone conclusion, and the possibility of a crisis in the next period of time is also reduced. In recent years, the American market economy has shown the characteristics of better than expected in the first quarter and weaker than expected in the second quarter. Since January, the global price of medical copper tubes has gradually got rid of the main tone of this year's shock and decline. &Air conditioning copper tubes show signs of stabilizing and rebounding. The three-month copper on the London Metal Exchange once rebounded nearly 7% from the year's low point, and the market price has rebounded to around 7600 dollars per ton. Driven by this, products including aluminum, zinc and other products have also rebounded. Only nickel, a basic metal product, has remained weak.

.In addition, brass has a unique sound, so the gongs, cymbals, bells, horns and other instruments in the East, as well as the western brass instruments, are all made of brass, with good processing performance and high conductivity. It is mainly divided into copper tube (copper zinc alloy, cheaper). The manufacturing principle of copper tube: All elements without exception reduce the conductivity and thermal conductivity of the copper bar. All elements are dissolved in the copper bar, causing lattice distortion of the copper bar, causing wave dispersion when free electrons flow in a directional direction, increasing the resistivity. On the contrary, there are no or few elements with solid solution in the copper bar which has little impact on the conductivity and thermal conductivity of the copper bar, Special attention should be paid to the fact that the solid solubility of some elements in the copper bar decreases sharply with the decrease of temperature. The precipitation of simple substances and metal compounds can not only strengthen the copper bar alloy by solid solution and dispersion, but also reduce the conductivity slightly. This is an important alloying principle for the study of high-strength and high conductivity alloys. Here, it should be pointed out that the alloy composed of iron, silicon, chromium and copper bar is a very important high-strength and high conductivity alloy; As the influence of alloy elements on the properties of copper bars is superposition, CoCrZr series alloys are * high-strength and high conductivity alloys; It is not easy to heat. Semi continuous casting copper tube has excellent conductivity. Copper tube has excellent conductivity. Alloy copper to ensure safety and fatigue resistance. Tin phosphor bronze jack adopts hard wire electrical structure without rivet joint or conflict contact, good elasticity and smooth dial. Phosphor bronze has high corrosion resistance, wear resistance, and will not produce sparks when stamping. It is used for medium speed and heavy load bearings. The working temperature is up to 250 ° C, and the active centering is insensitive to deflection. The bearing force is uniform, and the bearing capacity is high. It can withstand radial load and self lubrication without protection. The company is a manufacturer specializing in the production of various bronze tubes, bronze rods, bronze plates and profiled bronze profiles. Technical advantages: The maximum diameter of bronze bars and pipes can reach 300mm while that of plates can reach 600mm. The wall thickness of bronze tube can be as small as 4mm. The copper tube is a common bronze material. The aluminum content of copper tube generally does not exceed 5%. Sometimes, nickel, manganese and other elements are added to further improve the performance. It has high strength and good wear resistance. It is used for copper sleeves and wear resistant parts with high strength. The outstanding feature of t2 copper tube is its good wear resistance. The difference between copper tube and copper tube The copper tube is a copper based alloy with aluminum as the main alloy element. The copper tube is a copper based alloy with tin as the main alloy element. The mechanical properties of copper tube are higher than that of copper tube. The aluminum content of the copper tube in practical application is between 5% and 12%, the aluminum content is 5% and the 7% copper tube has good plasticity and is suitable for cold working.

Handle carefully to prevent damage and scratches. 2 When installing the keel, avoid collision between the basket and the keel. When installing the external wall hanging plate, protect it from impacting the medical copper pipe. 3 After the installation of thermal insulation curtain wall, in order to prevent personnel from approaching, special personnel should check the distance from the ground curtain wall. 4 For each process close to the curtain wall, the medical copper pipe shall be temporarily protected before construction and can be covered with fiberboard. Even after the construction is completed, some temporary protective measures should be taken to achieve the effect of later use. 3 On the premise of considerable cohesiveness, the exterior wall external thermal insulation decorative integrated board of high-rise buildings should meet the principle of flexible gradual change, and disperse and absorb seismic stress as far as possible to reduce the impact on medical copper pipes. 4 The medical copper pipe shall be made of waterproof and moisture permeable external insulation materials to avoid damage to the wall caused by water or steam migration. 5 Under the action of negative wind pressure, the volume expansion of the air layer in the insulation layer will damage the insulation layer. The aging of medical copper pipe will affect the use of building materials to a certain extent. When it reaches its service life, it needs to be replaced to prevent the trouble of aging in life. 6 The thermal expansion and cold contraction caused by the temperature difference change will cause the volume change of the non structure of the medical copper tube. Such medical copper tube has a shorter service life than the plate in normal use, and needs regular maintenance according to regulations.

Manufacture gear,Milan40Mn2 alloy steel plate, shaft sleeve, worm gear and other high-strength wear-resistant parts and high corrosion resistance elastic components. Key points of semi continuous casting process for copper tube: The copper tube has strong air absorption, easy oxidation and slag formation, large solidification shrinkage, poor thermal conductivity and other casting properties, and poor casting performance; Before casting, some alkaline earth metal compounds, such as Na3A lF6 and NaF mixture, are used as slag removers to purify the copper liquid which is effective for improving the purity of liquid metals and the crystal structure of ingots. The pouring temperature of copper pipes is generally 1120~1180 ℃, and the pouring temperature of large-sized ingots is generally lower. The casting speed of the copper tube is low, ensure that the liquid level in the funnel is always kept at a certain height so that the scum on the liquid level cannot flow into the crystallizer from the funnel hole; The copper tube ingot is easy to produce air holes and concentrated shrinkage cavities. At the end of pouring, the joint coating must be carefully carried out to avoid concentrated shrinkage cavities in the ingot. The red copper tube is a bar shaped object made of copper and zinc alloy, named after its yellow color. Copper content is 56%~68% brass, and its melting point is 934967 degrees. Brass has good mechanical properties and wear resistance, ship parts, gun casings, etc. Different zinc content also has different colors. For example, when the zinc content is 18%, 20% will be red and yellow, while when the zinc content is 20%, 30% will be brown and yellow.


Milan6063 aluminum tubeDisputes in the field of trade



The material cost of medical copper tube will not be less than 40 yuan. The better the material is, the higher the price will be. It is called &one cent one cent&. Moreover, in addition to the production and operation costs, labor costs, factory rent, etc. you must pay attention to the quotation below 45 yuan/square. Medical copper tubes are more and more widely used in the decoration of building exterior walls. In cold cities in the north, the quality and firmness of medical copper tubes have been improved. However medical copper tubes can play a very good role in decoration and insulation. With the continuous progress of science and technology, as long as the decoration materials are used, they will inevitably crack during installation and construction. As time goes by, there will be aging to varying degrees in daily life. Next, Zhongsheng Thermal Insulation Technology will introduce how to prevent the cracking of medical copper tubes and how to prevent the aging of medical t2 copper tubes? Let's talk about these two issues. How to prevent cracking of medical copper pipes To avoid cracks, buildings should be fully insulated, including awnings and other components. Through the quality and construction methods of external medical copper pipes, the construction quality can reach By reducing the ratio of the linear expansion coefficient of external thermal insulation materials of the building structure to the linear expansion coefficient of materials such as external decoration leveling mortar and external decoration surface, gradual changes will occur between medical copper pipes layer by layer, and the stress can be flexibly released, To prevent cracking. How to prevent medical copper tube from aging? The insulation layer of high-rise buildings shall have fire resistance , and shall have the characteristics of preventing fire spread and releasing smoke or toxic gas in case of fire. The strength and volume of materials shall not be reduced too much, and the surface shall not burst or collapse. Medical copper tube Medical copper tube is a new type of plate which is popular in China in recent years. It has many advantages such as good heat preservation, fire insulation, sound insulation, beautiful appearance, and is deeply welcomed by the industry. The medical copper pipe may fall during use. In order to reduce the occurrence of this kind of phenomenon, Jinan Zhongsheng Thermal Insulation Technology made a detailed ysis. Next, we will introduce the reasons for the fall of the external wall of the medical copper pipe and how to protect the medical copper pipe during installation. Reasons for the fall of the external wall of the medical copper pipe The medical copper pipe was not firmly fixed and moved, forming a push-pull effect, leading to the fall of the insulation layer. 3 At the connection between the concrete beam column and the masonry, the medical copper pipe is easy to fall off due to the deformation of the masonry. 4 Scaffold holes are not solid, forming insulation layer, and local base course is not firm and damaged. 5 The surface load of the medical copper tube is too large, or the anti negative wind pressure measures are unreasonable.

At the opening this morning, the market price of Zhengzhou copper bar was basically stable. According to the monitoring data of the Lange cloud business platform, the current market price of 57 * 5mm Linyi copper bar was 5400 yuan (ton price, the same below), the 108 * 5mm copper bar was 5250 yuan, and the 219 * 8mm copper bar Henan copper bar was 5200 yuan.

The price can be changed, and the transaction is affected. According to the feedback from the spot operation, the morning market transaction did not follow the temperature rise: after 9:00, the dealers took turns to raise the price which was in disorder; Before ten o'clock, it was not as expected, and users were very cautious in purchasing; Around 11:00, the surrounding markets became loose and the price was low. High hanging, low selling, and low volume. The market transaction is carried out in such a trilogy, which is different from the opening. In this process the mentality of traders has changed: from &turning to shipping&, after all, it has promoted the steel mill to sell before entering their own mouth? This is a &manic& market again: failed to continue to rise, and the market transaction is weak - this week's trading days, the spot price rose, and the transaction was less than expected. As of noon, the sales volume of large inventory customers was hundreds of tons, and the shipment was not much. Judging from the transaction in the morning, the selling price of leading resources rose generally. Among the resources in Kuti, the base price of t2 copper tube was 5050 yuan/ton, and the price of earthquake resistant spiral snail was 5350 yuan; Among the resources provided by the factory, the basic price of threads of Zhongtian, Yonggang and Shagang is 5130 yuan, and the differential between spiral and t2 copper pipes is 360-380 yuan/ton. In terms of the market, the leading market Tangshan narrow band mainstream fell by 30-120 in the early opening. The overall trading situation of copper bars was weak. Some small factories cut prices significantly, and the low price trading was acceptable. Limited production continues, market resources are average, weak market, and downstream procurement is cautious. 355 is the consolidation of the medium broadband market. Today's futures continue to fluctuate. Traders are less willing to ship at low prices and have a strong mood. However, under the pressure of futures, the trading atmosphere in the spot market is not good. Copper bars continued to fluctuate in the morning, and traders were affected by multiple factors to make a small weak tone trial deal. From the commercial account, we know that there are few high market transactions, few inquiry calls, and a slightly pessimistic attitude. The overall market transaction atmosphere is light, and most merchants operate on the market. At present, the downstream demand is still low, the demand for terminal replenishment is low, and the purchasing enthusiasm is not high. According to traders' feedback, the current market is in a weak situation of supply and demand. Downstream feedback shows that many projects are shut down and there is a great pressure on funds. However, the relevant economic data and side news are too bearish, so the futures market is difficult to rebound, and the spot market is mainly responsible for the subsequent drop. However, some traders are still willing to maintain their prices, which is mainly due to the high price of post settlement resources and the low inventory at present. The invention relates to a manufacturing method for a double seal socket flexible connection structure of a large diameter spiral welded steel pipe.

Click to view.There are also some serious corrosivity, and some fine sand or vegetable oil coating will appear when the plastic coated copper tube packaging materials and packaging are stored according to special requirements. It can adhere to the surface layer and form excellent passivation effect on the surface layer of the plastic coated copper pipe. When cleaning, a cleaning plan is required. The plastic coated copper pipe must transport some raw oil in the industry. The plastic coated copper pipe has good air tightness to ensure no leakage of gasoline and diesel. It is a good transmission pipeline.

For the production and processing of sculpted copper tubes the sheet metal shall be first opened in the sheet metal workshop according to the dimensions shown in the drawings, which is commonly referred to as opening. Then cut the corners of these open sheets according to the height of the edge, and then use the bending machine to form the edge according to the drawing forming diagram. The shaped copper pipe shall also be installed with reinforcing ribs as required, and the four corners of the shaped plate shall be welded well. The welded parts shall be sent to the grinding workshop, and the spraying surface shall be polished and the welding interface shall be polished and leveled. The polished modeling copper pipe is then sent to the spraying workshop for processing. Before spraying, the surface of the sculpted copper pipe shall be chrome treated and the process hole shall be drilled, so as to ensure that the sculpted copper pipe can be hung on the spraying line well, and the painting can be smooth without flow marks, and the color is consistent without color difference. After that, according to customer demand, the qualified products are pasted with protective film and bound with bubble film or wooden box.

The degreased copper tube is made of oxygen free copper rod, which has good processing characteristics and can be punched, bent and other process design requirements. The surface can be subject to anti-corrosion treatment, such as nickel plating, tin plating, zinc plating, etc. The surface anti-corrosion can reach 72 hours of fog test. The surface tin plating is environment-friendly lead-free tin, and the surface tin layer supports soldering. T2 degreased copper tube is mainly used for communication cabinet transformer, charging pile, box type substation and other electrical facilities. The copper bar is harder than the plastic pipe and has the degree of common metal (the strength of the cold drawn degreased copper pipe is equivalent to that of the steel pipe with the same wall thickness). It is not easy to corrode and is resistant to high temperature and high pressure. It can be used in various applications. The main material of copper bar is copper. The melting point of copper is as high as 1083 ℃, so as long as it is used correctly, there is no need to worry about safety. When choosing to decorate the house, few people ask about the water supply pipe of the house. In fact, the material of water supply pipeline will greatly affect people's health. T2 copper tube has strong capacity. Escherichia coli in the water supply will not continue to breed in the degreased copper tube, and more than 99% of the water will disappear after entering the degreased copper tube for 5 hours. This biological characteristic is that there is a small amount of copper ions dissolved in water in the degreased copper tube, and copper ions have a strong ability. Copper and zinc plating can avoid rusting and show a zinc protective film to metal materials. The conductive metal material repair and color enhancement care agent I can generate the thickness of the metal material epoxy protection layer and the pipeline cathodic protection layer, which can resist extreme weather and is suitable for the long-term surface of metal materials. The actual effect of salt and water corrosion resistance is good. The copper bar tin plating can prevent the air oxidation of the copper bar and the connection surface of the copper bar. In addition, the melting of metal tin and copper will produce aluminum alloy, which will improve the adhesion of copper strip coating. In addition, the conductivity of metal tin is good. The purpose of copper and tin plating: effectively prevent copper from becoming verdant due to moisture, and also prevent copper from oxidizing/sulfurizing and blackening and affecting electricity. The service life of the tinned copper tube is several times or even more than ten times, which greatly increases the service life of the copper and plays a considerable role in protecting the copper. The of tinned metal surface treatment on copper bar is to avoid air oxidation. As the air in industrial production air, marine climate or cold air is easy to turn black or produce copper green when oxidized, the copper bar surface shall be tinned for the total area, the resistance and conductivity of the steel bar lap surface.With the continuous development of industry, the demand for plastic coated copper tubes is gradually increasing. Then how to apply wood grain paint on alloy pipes. Wood like paint is a kind of wood like paint. It is used for spraying plastic coated copper pipe and its process flow. Plastic coated copper pipe is mainly used to manufacture high-pressure alloy pipe for heating surface of water tube boiler with high pressure and above. In the morning market, the mainstream spot price quoted by Lianzhong was 7900-7950 yuan/ton, part of the producing areas recalled 50 yuan, and the mainstream tax inclusive base price in the market changed from strong to weak in the 7900-8100 plastic coated copper pipe supply and demand relationship. It was difficult for the price of plastic coated copper pipe in the Guangzhou market to fall sharply this week. Second, plastic coated copper tubes are widely used in superheaters, headers and main steam ducts of domestic HP, UHP and subcritical power plant boilers. Third, large diameter pipes are mainly used as headers and main steam pipes with steam parameters below 565 ℃.


Milan6063 aluminum tubeDisputes in the field of trade



The demand for t2 copper tubes is increasing. At the same time, in the market, the quality identification method of t2 copper tube for grid fittings is currently accompanied by rapid economic development. There are many kinds of sales, different types, different purposes, and different quality. Therefore, when purchasing, you should be clear and have certain selection skills. Here we introduce the quality identification method of t2 copper tube. The color of t2 copper tube depends on the color of t2 copper tube. Although the external color is a visible factor, the color of the product is closely related to its production process and quality control. If the product is bright in color and high in glossiness, it is generally superior to the product with poor color. The t2 copper tube with uniform thickness should be selected. Because some small manufacturers are limited in technology and process, it is difficult to ensure that the product thickness is uniform and neat. Therefore, the thickness is also an important factor to test the quality of the pattern plate. Later, the casting process of t2 copper tube.

OK or not?.Air conditioning copper pipe is a common metal material in daily work of industrial production. The conductivity, heat conduction and corrosion resistance are excellent, and the W shape trend of air conditioning copper pipe is depressed due to the high copper content. Good machinability fusion welding and brazing are very good. The cutting of air conditioner copper pipe is a very energy consuming work. The following items need to be paid attention to in order to cut neat and beautiful parts. Before cutting the air conditioner copper pipe, the cutting machine should carry out calibration and other operations. You can try to use scrap metal first to prevent machine problems from causing me to cut off defective products.

[2] Welding process of copper pipe Clean the end and seven ports of steel pipe with steel wool. Do not use abrasive cloth or abrasive paper to clean, quartz sand is used as sand intercalation layer on the long distance uniform pavement in the middle of chemical fiber. Its wall thickness and structure are reasonable, and the plastic coated copper pipe laying process stipulates that the plastic coated copper pipe is a non-metallic material pipe with light quality, high strength and corrosion resistance. The glass fiber with epoxy resin based weight relief is coiled on the rotating hollow floor step by step according to the processing technology. It can make full use of the efficacy of raw materials, achieve the goal of applying compressive strength, improve the strength and stiffness, and ensure the reliability and stability of t2 copper tube. FRP sand pipe is accepted by many customers because of its excellent resistance to solvent erosion, light weight, strong durability, long service life compared with ordinary seamless steel pipe, low comprehensive project cost, convenient installation, reliability and other advantages. Plastic coated copper pipe is used in: gray and black metallurgy industry, nonferrous plate metallurgy industry, power industry, coal engineering, petroleum industry, chemical industry electromechanical engineering industry, cotton textile, vehicle and motorcycle processing and manufacturing industry, railway line for industrial production, shipbuilding, engineering construction, light industry, food industry, electronic industry, power, culture and art, sports culture and game entertainment, agriculture and animal husbandry, treatment and health and its national defense and civilian industries.

Air conditioning copper pipe is a common metal material in daily work of industrial production. The conductivity Diagnosis, and the W shape trend of air conditioning copper pipe is depressed due to the high copper content. Good machinability, fusion welding and brazing are very good. The cutting of air conditioner copper pipe is a very energy consuming work. The following items need to be paid attention to in order to cut neat and beautiful parts. Before cutting the air conditioner copper pipe, the cutting machine should carry out calibration and other operations. You can try to use scrap metal first to prevent machine problems from causing me to cut off defective products.

Now let me talk about the damages that are easy to occur on the surface of the copper tube. In order to prevent the accumulation of process agents or products and/or dirt, scratches and other rough surfaces, mechanical cleaning must be carried out. If the copper pipe is heated to a certain high temperature in the air during welding or grinding, chromium oxide heat return color will appear on both sides, lower surface and bottom of the weld. The color after tempering is thinner than that of the oxidation protective film, and is clearly visible. The color depends on the thickness. The thicker oxide can be found in the rainbow color, blue, purple to brown. It is usually black. It is caused by being at high temperature or being at high temperature for a long time. When any of these oxide layers exist, and the corrosion resistance of these areas will. In this case, it is not only necessary to heat temper the color and other oxide layers, but also to clean the chromium poor metal layer under it. Free iron on the surface of t2 copper tube will rust, causing corrosion of stainless steel. Therefore, the powder that must float can usually be removed together with the dust. Some are very sticky and must be treated as embedded iron. In addition to dust, there are many surface iron sources, including cleaning with ordinary carbon steel wire brush and shot peening with sand, glass beads or other abrasives previously used on ordinary carbon steel, low alloy steel or cast iron, or regrinding non stainless steel products attached to copper pipe components and equipment. If there is no protection during cutting or hoisting, the wire ropes, slings and iron on the working surface can easily be embedded or dirty the surface. The copper tube shall be boiled in boiling water for 30 seconds before cold treatment. The effective internal stress is about 15%, and the residual austenite reaches the effect. Then, the cold treatment can be carried out as usual. Of course, the second suggestion is to choose the normal treatment at minus 60 degrees, and then conduct deep cooling at minus 120 degrees. The lower the treatment temperature is, the retained austenite will be rapidly transformed into martensite, but it cannot be transformed. Through experiments, it can be found that there will be about 2% of retained austenite. At this time,MilanRed copper tube, retained retained austenite can achieve a certain buffer effect. After cold treatment, the air conditioning copper pipes need to be taken out and put into hot water for heating, which can effectively heat about 40% of the cold treatment stress. Tempering and cold treatment should be carried out as soon as possible after gradual heating, and most of them can avoid cracks as soon as possible, so as to ensure that the products will not deform in later use and facilitate daily storage. The transformation characteristics of the area of each layer of the copper tube during empty drawing affect the asymmetry of the deformation of the metal material. One of its characteristics is that the natural widening of each layer along the wall thickness is not consistent. Of course, the external layer of the copper tube is less, the internal surface layer of the copper tube is larger, and the natural widening of the middle layers is slow from the external layer to the internal surface layer.The technical level of degreasing copper tube for mechanical equipment With the substantial improvement of the manufacturing level of mechanical equipment and the degree of control automation in China, there is still some gap between the technical level of domestic degreasing copper tube production line and the products of foreign counterparts. After years of reform and opening up. The quality of all aspects of degreased copper pipe has also risen by several grades, significantly narrowing the quality gap with the imported production line. The aluminum hose production line and aluminum can production line developed and produced by the company break the technological monopoly of foreign companies, can provide stable and reliable production equipment for domestic and international markets, and make great contributions to the aluminum packaging industry. With the continuous improvement of people's living standards, there will be more and more demand for degreased copper tube products, and its market potential is huge. Problems such as incomplete penetration, deformation, cracks and air holes are easy to occur during the fusion welding of degreased copper tubes. Compared with fusion welding, wood is not melted during brazing, which reduces the impact of large thermal conductivity of base metal on welding quality, prevents the formation of incomplete penetration, reduces the tendency to produce pores and cracks, and ensures the performance of weld. Because the base metal is not melted, the structure and properties of the base metal are almost unchanged, so that the original service properties of the base metal can be maintained.