XigenAluminum rodStable operation of the industry

The medical copper tube 6 is superior to the exterior wall hanging plate decorative building materials. It will be affected by microorganisms in the air all year round accelerating the loss of its service life. 7 If the wall interface is not properly treated, the board surface also needs to be treated with interface mortar, the construction process must be strictly required, and the later maintenance work must be done well. 1 Place it in the rainproof shed, and do not place heavy objects on the surface.

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, which is a kind of non-ferrous metal processing bar, 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 wave dispersion when free electrons flow in a directional direction causing lattice distortion of the copper bar, 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, 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, which can ensure excellent touch, 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, an appropriate amount of iron, 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.

Xigen.Red copper is a kind of relatively pure copper, which can be generally considered as pure copper, with good conductivity and plasticity, but poor strength and hardness.

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, the chromium content on the metal surface will, 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, low alloy steel or cast iron, 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, 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, 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,XigenAluminum row of cold storage, so that the original service properties of the base metal can be maintained.

.Some problems. For example, in the preliminary manufacturing of copper tubes for air conditioners for automobiles, the materials for air conditioners can be selected according to the actual size required by users, and then the copper tubes for air conditioners for automobiles can be manufactured, followed by pickling. The produced copper tubes for air conditioners are put into the pickling tank for pickling, and then stretched. Then the pickled copper tubes for air conditioners are stretched according to their size requirements.

However, it may cause recoverable temporary damage to people who have been away from these radioactive sources for a long time. The DC brushless motor with small volume and large power is adopted, which can operate without fault for a long time even if it is opened or closed. Target There will be no sharp decline in the price of copper tubes in Linyi at the end of the month. The price of plastic coated copper pipe will continue. Pop up the position line and line, select PVD chromium nitride ring and molybdenum spraying ring as the matching materials for the plastic coated copper pipe, use the self-developed opposed reciprocating wear tester, carry out the load level test, wear test, lean oil test, and research the load. As for the corrugated process of the finished plastic coated copper pipe as claimed in claim 1, the radiation source for the engineering design of the integrated rigid flexible connection plastic coated copper pipe belongs to the low hazard source. Basically, it will not cause artificial damage. The basic principle of the foundation of the integral rigid flexible connection plastic coated copper pipe sluice discussed the influence of process parameters and heat treatment process on the microstructure, phase distribution and mechanical properties of the alloy, and obtained some important research results. The number of joints of steel pipes and plastic coated copper pipes on the same section shall not exceed 50% of the number of pipes. Before installation, the pipe shed shall sweep and clean the hole with drill bit or high-pressure air, and the scum in the hole shall be removed, Ensure the aperture (The hole diameter shall not be less than 127cm, and the hole depth shall meet the requirements to prevent hole plugging. Most of the seamless steel pipes produced now are hot-rolled. Because of the high temperature, the deformation resistance is relatively small, and generally the steel plate is used for rolling. In this operation, the detailed thickness of the steel plate shall also be considered. If it is about the harmful elements with relatively low accuracy requirements, plastic coated copper pipes must be required. The pipe shed can be installed, extended section by section, and What does plastic coated copper pipe with a diameter of 1 reflect in life when the weld length is added to 30 for the joint steel pipe of the pipe extension joint? Plastic coated copper pipe can also produce welded pipes with different pipe diameters from billets of the same width. However, it can be compared with straight seam pipes of the same length. The rental production rate is low.

The selection of medical copper tube table, these problems are natural.

Plastic coated copper pipe is one of the safe carbon fiber products. Its specific content is a new structural composite building decoration material that can be produced according to the development trend of production and manufacturing by using a glass fiber as the synergist and resin as the adhesive based on the application of full intelligent technical automatic control system equipment.

Copper is light.

The operation is very convenient. The forward and reverse switches are set on the front panel and can be toggled up and down. The advantage is power saving (efficiency 90%, time saving (only two thirds of the time of the original rectifier, or even shorter), material saving (at the same time, raw materials can be saved 30%, and efficiency is high (more than one third of the output value of each savings). The degreased copper tube has less deformation resistance and is easier to form. The original color of copper should be orange or rose, but it is easy to oxidize into purple in the air, so it is also called degreasing copper tube. In terms of conductivity and thermal conductivity, brass rod has no hardness of copper rod, and degreased copper tube is inferior to copper wire. The defatted copper tube Huangtong brand has its own advantages and disadvantages, but the differences are also luminous points. Can affect people's lives, copper bus is widely used in electrical equipment, especially in complete power distribution equipment. The UVW phase bus and PE bus in the general distribution cabinet are copper bus; In use, copper bus bars are generally marked with colored letters or painted with colored paint.

Statistics.When I need to use more quantity, what are the factors that cause the surface corrosion of copper tubes. Introduce the factors that cause the surface corrosion of copper tubes. Surface pollution: The oil, dust acid, alkali, salt, etc. attached to the surface of the workpiece will be converted into corrosion medium under certain conditions, which will react with some components in the stainless steel parts to produce chemical corrosion and rust.

In addition, the stress corrosion cracking inside the stainless steel plate will cause the transition film on the surface of the stainless steel plate. Therefore, the surface of plastic coated copper pipe shall be cleaned to a certain extent to ensure its service life. The oil cracking tube circuit breaker must be selected. The fracture of the plastic coated copper pipe shall be kept on a true circle, so moderate energy shall be used when cutting square steel pipe. What matters should be paid attention to when purchasing plastic coated copper tubes.

Some problems. For example, in the preliminary manufacturing of copper tubes for air conditioners for automobiles the materials for air conditioners can be selected according to the actual size required by users, and then the copper tubes for air conditioners for automobiles can be manufactured, followed by pickling. The produced copper tubes for air conditioners are put into the pickling tank for pickling, and then stretched. Then the pickled copper tubes for air conditioners are stretched according to their size requirements.

The large diameter coated medical copper tube can deform to prevent the risk of ductile damage; The medical copper tube has sufficient plastic deformation, and the medical copper tube is capable of deformation. It is stipulated that the plastic deformation and ductility of medical copper tubes are good. Good plastic deformation can ensure that the structure can have significant deformation before destruction. In some peak periods of the structure, the tectonic stress will be redistributed, which makes the tectonic stress spread gently. Good ductility indicates that under dynamic and static loads more kinetic energy should be digested and absorbed when the structure is destroyed, which is the risk water of ductile destruction. For the structures with plastic deformation design scheme and the structures in disaster areas, the size of the deformation working capacity of medical copper tubes has a particularly critical practical significance. 3 Production and processing characteristics of medical copper tubes. It can be integrated with cold and heat treatment, and will not cause great harm to compressive strength, plastic deformation and ductility due to such production and processing. 4 Weldability of medical copper tube. The welding of medical copper tube is a rapid heating and cooling process. The metal materials in the welding and heat affected zone need to go through heating and melting, cooling and crystallization, and solid state change in a very short time. The industry trend is a kind of medical copper tube. Because there is no seam in the middle, it has more advantages in strength. Medical copper tubes have many different s in practical application, and each different will make the medical copper tube work well.Advantages of medical copper tubes: compared with solid copper tubes such as round steel, torsional strength and tensile strength, and their net weight is relatively light. One is plastic copper tubes cut for social and economic development, which are widely used in the production and processing of spare parts and mechanical parts, such as oil drilling equipment, rotating shafts, bicycle frames, and steel medical copper tube frames used in engineering construction. This kind of welded medical red copper pipe is developed under the special conditions that the temperature is all over and the composition is extremely unbalanced. After this kind of welding, it can produce detailed welding joints to maintain special performance indicators, which is the specified weldability. 5 Performance of medical copper tube. It refers to the service life of medical copper tube. The production and processing of annular parts with medical copper tubes can achieve the utilization rate of raw materials, simplify the production process, save raw materials and manufacturing hours such as needle bearing throw rings, etc. At present, medical copper tubes have been widely used for production and processing. Disadvantages of medical copper tubes: medical copper tubes are also indispensable raw materials for various strategies. Drums must be produced and processed by medical copper tubes. Medical copper tubes can be divided into round medical copper tubes and profiled steel according to their different cross-sectional areas. Due to the large circle area under the same diameter specification, the annular pipe can be used to transport many large diameter medical copper pipes. Large diameter coated medical copper pipes are widely used in tap water, natural gas petroleum, chemical industry, communication, power, marine and other engineering fields. There is no solvent in the coating and no leakage, so it will not pollute the medium transported, without aging and cracking, so it can be used in cold areas and other harsh conditions. When processing medical copper tubes, the medical copper tube factory will use pickling, which is an indispensable part of most medical copper tubes, Pickling process is the treatment after removing surface oxide scale (Carbon steel - stainless steel - lime saponified phosphorus butter, oil, copper and aluminum pipes - and the old ones,XigenAluminium tube, and then wire drawing processing. Then what are the points to be noted when washing? 1 When washing the medical copper pipes, they need to be carried out in the flowing clear water tank, so as to avoid secondary pollution. When washing, the medical copper pipes need to be fully immersed in water. At this time, the sling should be relaxed, and it can be lifted up and down three to four times. If the medical copper tube is not acid resistant, the surface may be oxide and oil, and the phosphating solution cannot remove nuclear energy. However, after acid washing of medical copper tubes, water washing is also required. 2 When the medical copper tube is washed, the water in the medical copper tube needs to be cleaned to avoid water corrosion and oxidation of the medical copper tube. Therefore, it is necessary to carry out solvent treatment as soon as possible. 4 When the medical copper tube is washed, the iron salt content must be controlled within a certain range, and it cannot exceed the standard, otherwise the medical copper tube may be damaged.

Meticulous workmanship.The large diameter coated medical copper tube can deform to prevent the risk of ductile damage; The medical copper tube has sufficient plastic deformation, and the medical copper tube is capable of deformation. It is stipulated that the plastic deformation and ductility of medical copper tubes are good. Good plastic deformation can ensure that the structure can have significant deformation before destruction. In some peak periods of the structure, the tectonic stress will be redistributed, which makes the tectonic stress spread gently. Good ductility indicates that under dynamic and static loads, more kinetic energy should be digested and absorbed when the structure is destroyed, which is the risk water of ductile destruction. For the structures with plastic deformation design scheme and the structures in disaster areas, the size of the deformation working capacity of medical copper tubes has a particularly critical practical significance. 3 Production and processing characteristics of medical copper tubes. It can be integrated with cold and heat treatment, and will not cause great harm to compressive strength, plastic deformation and ductility due to such production and processing. 4 Weldability of medical copper tube. The welding of medical copper tube is a rapid heating and cooling process. The metal materials in the welding and heat affected zone need to go through heating and melting, physical reflection, cooling and crystallization, and solid state change in a very short time. The industry trend is a kind of medical copper tube. Because there is no seam in the middle, it has more advantages in strength. Medical copper tubes have many different s in practical application, medical copper tubes have the same tensile strength, torsional strength, and tensile strength, and their net weight is relatively light. One is plastic copper tubes cut for social and economic development, which are widely used in the production and processing of spare parts and mechanical parts, such as oil drilling equipment, bicycle frames, and steel medical copper tube frames used in engineering construction. This kind of welded medical red copper pipe is developed under the special conditions that the temperature is all over and the composition is extremely unbalanced. After this kind of welding, simplify the production process, save raw materials and manufacturing hours such as needle bearing throw rings, hydraulic jack sleeves, etc. At present, medical copper tubes have been widely used for production and processing. Disadvantages of medical copper tubes: medical copper tubes are also indispensable raw materials for various strategies. Drums must be produced and processed by medical copper tubes. Medical copper tubes can be divided into round medical copper tubes and profiled steel according to their different cross-sectional areas. Due to the large circle area under the same diameter specification the annular pipe can be used to transport many large diameter medical copper pipes. Large diameter coated medical copper pipes are widely used in tap water, natural gas, petroleum, chemical industry, communication, power, marine and other engineering fields. There is no solvent in the coating and no leakage, so it will not pollute the medium transported, thus ensuring the purity and hygiene of the fluid. The temperature range from - 40 ℃ to+80 ℃ can be used alternately in cold and hot cycles, without aging and cracking, so it can be used in cold areas and other harsh conditions. When processing medical copper tubes, the medical copper tube factory will use pickling, which is an indispensable part of most medical copper tubes, Pickling process is the treatment after removing surface oxide scale (Carbon steel - stainless steel - lime saponified phosphorus, butter, oil, copper and aluminum pipes - and the old ones, and then wire drawing processing. Then what are the points to be noted when washing? 1 When washing the medical copper pipes, they need to be carried out in the flowing clear water tank, so as to avoid secondary pollution. When washing, the medical copper pipes need to be fully immersed in water. At this time, the sling should be relaxed, and it can be lifted up and down three to four times. If the medical copper tube is not acid resistant, the surface may be oxide and oil, and the phosphating solution cannot remove nuclear energy. However, after acid washing of medical copper tubes, water washing is also required. 2 When the medical copper tube is washed, the water in the medical copper tube needs to be cleaned to avoid water corrosion and oxidation of the medical copper tube. Therefore, it is necessary to carry out solvent treatment as soon as possible. 4 When the medical copper tube is washed the iron salt content must be controlled within a certain range, and it cannot exceed the standard, otherwise the medical copper tube may be damaged.

Disadvantages: Due to loose tissue and high pressure resistance, the pipe is only used to produce small air conditioning copper rods.

No heating and plating bath is required. The process is simple and easy to operate. The cold drawn degreased copper tube bright tin plating is one of the anti discoloration mirror bright brush tin plating and degreased copper tube tin plating mean copper bar partial or overall tin plating.

Xigen.Plastic coated copper pipe is one of the safe carbon fiber products. Its specific content is a new structural composite building decoration material that can be produced according to the development trend of production and manufacturing by using a glass fiber as the synergist and resin as the adhesive based on the application of full intelligent technical automatic control system equipment.

The large diameter coated medical copper tube can deform to prevent the risk of ductile damage; The medical copper tube has sufficient plastic deformation, and the medical copper tube is capable of deformation. It is stipulated that the plastic deformation and ductility of medical copper tubes are good. Good plastic deformation can ensure that the structure can have significant deformation before destruction. In some peak periods of the structure, the tectonic stress will be redistributed, which makes the tectonic stress spread gently. Good ductility indicates that under dynamic and static loads, more kinetic energy should be digested and absorbed when the structure is destroyed, which is the risk water of ductile destruction. For the structures with plastic deformation design scheme and the structures in disaster areas, the size of the deformation working capacity of medical copper tubes has a particularly critical practical significance. 3 Production and processing characteristics of medical copper tubes. It can be integrated with cold and heat treatment, plastic deformation and ductility due to such production and processing. 4 Weldability of medical copper tube. The welding of medical copper tube is a rapid heating and cooling process. The metal materials in the welding and heat affected zone need to go through heating and melting, physical reflection, cooling and crystallization, and solid state change in a very short time. The industry trend is a kind of medical copper tube. Because there is no seam in the middle, it has more advantages in strength. Medical copper tubes have many different s in practical application, and each different will make the medical copper tube work well.Advantages of medical copper tubes: compared with solid copper tubes such as round steel, medical copper tubes have the same tensile strength, torsional strength, and tensile strength, and their net weight is relatively light. One is plastic copper tubes cut for social and economic development which are widely used in the production and processing of spare parts and mechanical parts, such as oil drilling equipment rotating shafts, bicycle frames, and steel medical copper tube frames used in engineering construction. This kind of welded medical red copper pipe is developed under the special conditions that the temperature is all over and the composition is extremely unbalanced. After this kind of welding, it can produce detailed welding joints to maintain special performance indicators, which is the specified weldability. 5 Performance of medical copper tube. It refers to the service life of medical copper tube. The production and processing of annular parts with medical copper tubes can achieve the utilization rate of raw materials, simplify the production process, save raw materials and manufacturing hours, such as needle bearing throw rings, hydraulic jack sleeves, etc. At present, medical copper tubes have been widely used for production and processing. Disadvantages of medical copper tubes: medical copper tubes are also indispensable raw materials for various strategies. Drums must be produced and processed by medical copper tubes. Medical copper tubes can be divided into round medical copper tubes and profiled steel according to their different cross-sectional areas. Due to the large circle area under the same diameter specification, the annular pipe can be used to transport many large diameter medical copper pipes. Large diameter coated medical copper pipes are widely used in tap water, natural gas, petroleum, chemical industry, communication, power, marine and other engineering fields. There is no solvent in the coating and no leakage, so it will not pollute the medium transported, thus ensuring the purity and hygiene of the fluid. The temperature range from - 40 ℃ to+80 ℃ can be used alternately in cold and hot cycles, without aging and cracking, so it can be used in cold areas and other harsh conditions. When processing medical copper tubes, the medical copper tube factory will use pickling which is an indispensable part of most medical copper tubes, Pickling process is the treatment after removing surface oxide scale (Carbon steel - stainless steel - lime saponified phosphorus, butter, oil, copper and aluminum pipes - and the old ones, and then wire drawing processing. Then what are the points to be noted when washing? 1 When washing the medical copper pipes, they need to be carried out in the flowing clear water tank, so as to avoid secondary pollution. When washing, the medical copper pipes need to be fully immersed in water. At this time, the sling should be relaxed, and it can be lifted up and down three to four times. If the medical copper tube is not acid resistant, the surface may be oxide and oil, and the phosphating solution cannot remove nuclear energy. However, after acid washing of medical copper tubes, water washing is also required. 2 When the medical copper tube is washed, the water in the medical copper tube needs to be cleaned to avoid water corrosion and oxidation of the medical copper tube. Therefore, it is necessary to carry out solvent treatment as soon as possible. 4 When the medical copper tube is washed, the iron salt content must be controlled within a certain range, and it cannot exceed the standard, otherwise the medical copper tube may be damaged.

The materials of the packer shall be packed with steel strip and added according to the diameter and weight of the petroleum cracking pipe. The degreased copper pipe from the pipe can be packed without a packer. If there are wiring ports on both sides of the cracked oil pipe, external thread devices shall be provided for safety protection. Brush the nozzle with clean oil or anti rust oil. For the cracks on both sides of the petroleum cracking pipe, branch pipe safety protectors can be installed on both sides as required. If the oil cracking pipe is installed in the container, the container shall be lined with waterproof devices, such as woven cloth and straw mats. In order to better distribute the textile petroleum cracking tubes in the tank, the packer can weld the safety protection support frame inside the petroleum cracking tubes. Previous page: How to clean plastic coated copper tubes. What problems will be encountered when cutting plastic coated copper pipe. What problems will be encountered when cutting plastic coated copper pipe. What problems will be encountered when cutting plastic coated copper pipe. When plastic coated copper pipe is cut, the position and direction shall be drawn with tape or other measuring tools and the disconnection line shall be marked in combination with the construction drawing and site conditions. When the petroleum cracking pipe is disconnected, please fix the equipment with square steel pipes such as vises, and cut it after fixing. In the area to be disconnected, use a towel or soft cloth to crack the oil stain or dirt on the surface of the pipe. As we all know, if steel pipes are exposed outdoors for a long time, or there are some, they will damage the air oxide layer on the surface of the stainless steel plate, and then oxidize and rust in the cold. Gas. Therefore, the steel pipe shall be placed in the sealing area as far as possible. However, plastic coated copper tube has incomparable advantages, because its surface is not easy to be oxidized, which is the key to constitute the raw material of plastic coated copper tube. The high-precision plastic coated copper pipe has an extremely thin, firm and smooth chromium rich air oxide film on its surface to prevent oxygen molecules from re penetrating and re oxidizing in the air, thus preventing rust. The description of the plastic coated copper pipe shows that the part with weak corrosion resistance of the transition film will produce pitting corrosion reaction due to the self-excited reaction, and the small holes will form highly corrosive aqueous solution. The chloride ion content will accelerate the corrosion rate.