Matosinos321 stainless steel coiled platemonopoly

Four in one formula and process conditions Preparation of solution Take formula 1 as an example: mix the calculated amount of water for zinc oxide into a paste, slowly add it into the calculated amount of phosphoric acid under stirring until it is completely dissolved, then add zinc nitrate and tartaric acid, dilute it with water to 2/3 of the total volume add sodium alkosulfonate and OP emulsion, and stir to make it completely dissolved. Then add chromium dihydrogen phosphate dissolved in dilute phosphoric acid, and add titanium sulfate. After all materials are added, dilute them to the total volume, stir them to make the solution even, cool them to room temperature, put a large amount of iron filings in the solution and soak them for 2-3 days to make them contain enough ferrous ions. When the content of ferrous ion reaches above 7g/L, adjust the free acidity and total acidity of the solution to the specified value, and then the solution can be used at elevated temperature. When the ferrous ion reaches the above value, the phosphating speed is fast, the solution is stable, and the phosphating film is fine and dense. During operation, attention shall be paid to controlling the temperature. If the temperature is higher than 70 ℃, the degreasing technology of degreased copper pipe. How to make degreased copper pipe? The process flow of degreased copper tube? What are the characteristics of degreased copper tubes? Use of degreased copper tube? There are too many questions. Let's solve them at once. Everyone knows the copper tube. Nitrate reacts easily. The heater should be installed on the two walls of the tank, not on the bottom of the tank, to prevent local overheating. Stainless steel pipe or iron pipe should be used for heater, and lead pipe or copper pipe should not be used to avoid contamination of solution by impurities. What is degreased copper pipe? &The advantages of degreased copper pipe's comprehensive treatment of grease, rust removal phosphating and passivation are described. This comprehensive treatment process can simplify the process, reduce the work area, save equipment costs, shorten working hours, improve labor productivity and reduce costs. This method can only be used in the occasions where the requirements for coating quality are not high.However, in actual production, light and heavy rust, the consumption rate of each component in the solution is different, so attention should be paid to adjustment and control to maintain its due role. What is the degreasing copper tube? &I have roughly known the degreasing methods of degreasing copper tubes: solvent degreasing, alkali degreasing, ultrasonic degreasing, high pressure hot water degreasing, etc. 1 Solvent degreasing: use degreasing solvent to dissolve the oil on the surface of red copper pipe, collect it together into a container, volatilize,Matosinos321 stainless steel round steel, and separate the pollutants from the circulation system. This method was used in the early stage, which has problems such as low cleaning efficiency, difficult maintenance, and environmental pollution. In recent years, many kinds of surfactants have been developed.

The utility model relates to a connecting structure, in particular to a connecting structure of a copper tube and an aluminum row. At present, most of the copper aluminum transition joints have not been effectively protected. In this way, under the condition of long-time electrification and heating and affected by the water vapor or corrosive gas in the air, the parts at the connection point are more likely to be oxidized, resulting in the reduction of the effective contact area of the connection point, the increase of the contact resistance, and the excessive heating or even burning of the connection point.

Matosinos.Copper tube is also called copper tube nonferrous metal tube. It is a pressed and drawn seamless pipe, characterized by light weight, good thermal conductivity, high low-temperature strength and corrosion resistance. Because of these excellent properties of copper tubes, the use of copper tubes is very common. What are the differences between hard copper tubes and soft copper tubes in the use process? What are the differences between the two in terms of specific applications?

At the same time, it is also a necessary equipment in the family. With a table, no fingerprint disposal of medical copper tube is necessary in the catering industry. Only when you cook food can you have a place to enjoy it.

.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,MatosinosBronze tube, 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.

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, adhere to the wear form condition simulation criteria of the sample test, 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.

Xiao Bian would like to talk about the production of a copper tube for automotive air conditioners to help you better understand this product. During the production of automotive air conditioning copper tubes, and the tubes should be straightened to meet the requirements of automobiles for automotive air conditioning copper tubes. The air conditioner copper pipe straightener uses vertical and horizontal rubber rollers to straighten it attention should be paid to the use of straighteners in production, so that the air conditioner copper pipe can be used by users to a certain extent.Nowadays, most straighteners can only straighten some copper pipes for automobile air conditioners with low accuracy, while most straighteners with high accuracy can only straighten some copper pipes for automobile air conditioners with small defects. Therefore the straightening equipment used for rectangular pipes with different bending degrees is different, which brings a lot of inconvenience to the production of copper pipes for automobile air conditioners. Therefore, some other construction processes should be used, To solve some problems arising from the above production. For example, in the preliminary manufacturing of medical copper tubes for automobiles, the air conditioner copper tube materials can be selected according to the actual size required by the user, and then the air conditioner copper tubes for automobiles can be manufactured, followed by pickling, putting the produced air conditioner copper tube materials into the pickling tank for pickling, and then stretching, and then stretching the pickled air conditioner copper tubes according to their size requirements. The warehouse shall not be mixed with acid Alkali, salt cement and other materials that are corrosive to steel are stacked together. Air conditioning copper pipe is based on carbon structural steel. The phenomenon of torsional deformation of air conditioning copper pipe requires weeds and all sundries on the site. One or more alloy elements shall be added appropriately to improve the mechanical properties, it refers to a kind of air conditioner copper tube with equal side length. The automobile air conditioner copper tube is made of strip steel as raw material toughness and hardenability of the annealing steel. The automobile air conditioner copper tube is also called the air conditioner copper tube. In fact, and then processed and rolled by relevant processes. It is generally made into a circle after the strip rod is unpacked, straightened, curled and welded. Among them, hardness is an index to measure the degree of hardness and softness of automotive air conditioner copper tubes. At present, the commonly used hardness method for measuring product hardness in production refers to the use of an indenter with a certain geometric shape to measure the hardness value of the metal surface being tested under a certain load according to its degree of coverage. The air conditioner copper pipe in the automobile air conditioner copper pipe is also divided into weld and seamless. Seamless air conditioner copper pipe is a metal material formed by directly using seamless round pipe. The plasticity of the air conditioner copper pipe refers to the ability to deform under a certain load without its original performance. The copper pipe for automobile air conditioner is a hollow and square section. The light thin-walled copper pipe for air conditioner is also known as steel cold-formed profile. It is a square section steel made of strip or coiled plate after processing in the cold bending area and high-frequency welding. In addition to being used in the automobile industry, the air conditioning copper pipes are used in construction, machinery manufacturing, steel construction and other projects, shipbuilding, solar power generation support, steel structure engineering, electric power engineering, power plants, glass curtain walls, boiler construction, highway railings, pressure vessels, oil tanks, power station equipment, lifting and transportation machinery and other high load welding structures. In addition to the thickening of the wall, the size and external straightness of the extra thick wall air conditioning copper tube can both exceed the water content of the resistance welded cold formed air conditioning copper tube. Therefore, this kind of automobile air conditioning copper tube has better comprehensive mechanical properties and has the advantages of hot processing, cold processing, weldability and corrosion resistance.

Copper tube has good bearing capacity. For example, in large cities, road bridges and undersea bridges often appear. Most road bridges are built with plastic coated copper pipes. With plastic coated copper pipes, engineering construction in large cities will become stronger and stronger. The actual operator shall carry out the actual operation of the heating furnace, yze the materials of the heating furnace, determine the cleaning, because this kind of seamless steel pipe for heating furnace is mainly used for machining parts. Because the seamless steel pipe must be heated at high temperature during production and processing. What are the plastic coated copper tubes to prevent wear. What are the plastic coated copper tubes to prevent wear. We all know that all objects will wear in application, so how to prevent the wear of oil cracked pipes. Now let's introduce it to you. The packaging of petroleum cracking tubes shall be able to prevent and damage during normal loading, unloading, transportation and storage. If the Demander has special requirements for packaging materials and packages of petroleum cracking tubes, it shall be indicated in the contract; If it is not marked, the supplier shall select packaging materials and packaging. Packaging materials shall comply with relevant requirements. If the material is not packaged, it should be suitable for the intended use and avoid obvious and natural purification. If the customer stipulates that the surface layer of the cracked tubing should not be damaged by bumps, it can be considered to repair and install the cracked tubing in the middle. Rubber sleeves, tree trunks, straw ropes, fiber cloth, plastics, pipe caps, etc. can be used for maintenance and installation. The thick wall petroleum cracking pipe can choose the internal fulcrum or external structure. Because thick walled tubes are thin. The supporting frame and frame are made of steel, which is inconsistent with the plastic coated copper pipe. If the customer needs a packer, the petroleum cracking tube can be weighed in a decentralized way. However, the specification must be 159MM500MM.

Disadvantages of copper pipe As far as copper pipe is concerned, high production cost and high price are its biggest disadvantages. Compared with other pipe fittings, the cost of copper pipe is much higher, and the connection at the copper pipe interface requires high construction technology level.

The automobile air conditioner copper tube is also called the air conditioner copper tube. In fact, it refers to a kind of air conditioner copper tube with equal side length. The automobile air conditioner copper tube is made of strip steel as raw material, and then processed and rolled by relevant processes. It is generally made into a circle after the strip rod is unpacked, straightened, curled and welded. Among them, the commonly used hardness method for measuring product hardness in production refers to the use of an indenter with a certain geometric shape to measure the hardness value of the metal surface being tested under a certain load according to its degree of coverage. The air conditioner copper pipe in the automobile air conditioner copper pipe is also divided into weld and seamless. Seamless air conditioner copper pipe is a metal material formed by directly using seamless round pipe. The plasticity of the air conditioner copper pipe refers to the ability to deform under a certain load without its original performance. The copper pipe for automobile air conditioner is a hollow and square section. The light thin-walled copper pipe for air conditioner is also known as steel cold-formed profile. It is a square section steel made of strip or coiled plate after processing in the cold bending area and high-frequency welding. In addition to being used in the automobile industry, the air conditioning copper pipes are used in construction, machinery manufacturing, steel construction and other projects, shipbuilding, solar power generation support, steel structure engineering, electric power engineering, power plants, agricultural and chemical machinery, glass curtain walls, boiler construction, highway railings, housing construction, pressure vessels, bridges, power station equipment, lifting and transportation machinery and other high load welding structures. In addition to the thickening of the wall, cold processing this kind of automobile air conditioning copper tube has better comprehensive mechanical properties and has the advantages of hot processing, it is an improved spray type passivation box for t2 copper pipe production line. The installation step of the connection structure 100 between t2 copper pipe and aluminum bar belongs to the improvement of the spray type passivation box structure for t2 copper pipe production line. The passivation solution spray box is set above the side of the passivation solution box, the passivation solution spray box with downward sloping bottom is connected with the inlet of the passivation solution box by the outlet set on the box wall at the bottom of the inclined bottom, the inlet of the passivation solution box is located on the box wall above the passivation solution box, the upper side of the passivation solution box is installed with a passivation pump, and the inlet pipe of the passivation pump is connected with the passivation solution box, it is convenient for operators to add passivation liquid to the passivation box, clean colloidal crystals at the bottom of the passivation box avoid equipment blockage, avoid crystals adhering to the zinc layer on the surface of galvanized pipe, and improve the surface quality of galvanized steel pipe.

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.

Use the medical copper tube table to eat. Because of the unique of the medical copper tube, when the oil drops on the table, it will only stick to the table, but not penetrate the table. Only with a slight wipe of the rag, the oil stains will be easily disappeared. In this case, when cleaning large canteens, the liquidators do not need to spend much effort but are relaxed. They just need to prepare a rag and a basin of clean water, and then carefully scrub it. t2 Medical Copper Tube Company thinks that the medical copper tube table is only made of the surface of the medical copper tube, and its exterior is not made of the medical copper tube. The price is cheaper than the wooden table, which is extremely suitable for a small amount of purchase. The medical copper tube has a natural bright and beautiful feeling. The color is extremely blended, and can stop the very good embellishment and reaction with the color in the surrounding situations. Now, let's understand some STEPs of the appearance processing of medical copper tubes. There are about five different methods for the appearance processing of medical copper tubes. Connect to t2 Medical Copper Tube Company and introduce them to the master. In addition, these methods can also stop the combined processing and create more medical copper tubes with different appearances. No matter which method is used, the following STEPs should be followed. First, before processing, the agreement should be stopped with the manufacturer, and then a sample should be selected as the standard for future consumption. The second part, when using it, we should guarantee that the coils of the base we choose to use and the coils that are not yet used are the third of the same model and batch. If they are used in some construction, such as elevators, we should pay attention to the unexpected selection of materials. In some places with extraordinary contrast, it is not appropriate to use the mirror t2 medical copper tubes. When processing, it is necessary to select the appropriate manufacturing process, such as weld grinding, how to restore the appearance. Class For the processing of the appearance of some textured t2 medical copper tubes, pay attention to the bias, which is also called unidirectionality. For example, if the lines used are vertical rather than horizontal, it is not easy to apply the dirty residue on the appearance of t2 medical copper tubes. It is extremely easy when they are clean. When finishing, STEP of the process used should be added, so the cost also needs to be added. Therefore, when selecting the appearance of the processing, and when selecting the planning and design staff, they should have a full understanding of the appearance of t2 Medical Copper Tube. Since the birth of medical copper tube, chemical industry, crude oil, machine manufacturing and other industries for its superior . It is precisely because of this kind of universal needs that people are increasingly demanding for medical copper tubes. Although this kind of situation is basically conducive to the development of the medical copper tube industry. Having said so much, the editor of this website will introduce the most popular technology in the medical copper tube industry -- the medical copper tube appearance fingerprint free disposal punishment technology. Mentioned here, I believe that many enemies have learned the greatest advantages of this kind of technology from the name. However, do you know that this is nothing more than a contrast of significant and abstract advantages. The most one-sided introduction is also my face. The medical copper tube after adopting this kind of technical treatment has a smooth appearance and soft hand feeling, and ordinary dust and impurities are not easy to adhere. Therefore, it is also extremely easy to clean. If the ordinary dust is probably dirt, just wipe it with a wet rag and you will lose the clean and smooth appearance. Because the implementation of this kind of craft is to use electroplating oil to shine the film on the red interior line, so it has the characteristics of being tough and not easily scratched. This prevents the possibility that some slight bumps may damage the medical copper tube. It also allows the medical copper tube to be used twice as quickly. Stop the fingerprint free disposal and punish the medical copper tube after the accident. It also loses great promotion in appearance. As the saying goes, a superior appearance can always leave the best impression. Therefore compared with the medical copper tube after the punishment and the medical copper tube without the punishment, it can often be welcomed by customers and enemies.Hot rolling and hot expansion. The main processing procedures include the blank sawing process, and the production process of the air conditioning copper pipe in the tower mainly includes cold drawing. Ring furnace heating process, piercing process, pipe rolling process,MatosinosAluminum row of cold storage, sizing process, cooling bed process, straightening process, pipe cutting soot blowing process, magnetic flux leakage detection process, surface inspection, length measurement and weighing to packaging and warehousing. Key points: yield strength limit: when the external force borne by the air conditioning copper tube sample exceeds the elastic limit of the material, although the stress no longer increases, the sample still has obvious plastic deformation. This phenomenon is called yield, that is, when the material bears an external force to a certain extent, its deformation is no longer in direct proportion to the external force, resulting in obvious plastic deformation. The stress when the air conditioning copper pipe yields is called the yield strength limit, and the corresponding S point in the tensile test curve is called the yield point. For air conditioning copper pipes with high plasticity, there will be an obvious yield point on the tensile curve, while for materials with low plasticity, there will be no obvious yield point, so it is difficult to calculate the yield limit according to the external force at the yield point. Therefore, in the tensile test method it is usually specified that the stress when the gauge length on the specimen produces 0.2% plastic deformation is taken as the conditional yield limit, expressed as 0. The yield limit index can be used as the design basis for requiring that the parts do not produce obvious plastic deformation during operation.

It is still necessary to pay attention to the materials used for pipes and the hardness of materials, so as to comprehensively consider and avoid problems. The polymer is thermally copolymerized with the polymer to form the big data of the molecules connected by the ion bond of the co thermal polymerization. The thermal copolymerization is carried out according to the DA reverse reaction. The disadvantage of such materials depends on the fact that if simple heat treatment process is improved without additional metal catalyst, chemical formula or other unusual surface treatment of metal materials will lead to ionic bond in the area to be repaired and can open the gap several times. Copper tube concrete based textile materials. Self repairing concrete is a basic concept that mimics the automatic basic metabolism of some chemicals of the injured part by biological tissues, so as to make the injured part heal. Hollow glass fiber or liquid core optical fiber may damage the hollow bag of concrete raw materials, damage the hollow glass fiber or liquid core optical fiber, and flow the adhesive to the damaged part, so that the gap medical copper tube can be healed again. Cause of surface damage of copper tube. Copper tube is also a kind of material commonly used in engineering. The surface shall also be protected from scratches. The surface of the copper tube is also easy to be damaged, whether it is processed or stored in the warehouse.

Scheme customization.One of the classification of copper tubes. The common wave shape is a single copper tube. Hyperbolic means that two different arcs overlap on the same surface, that is, starting from different circle centers, draw arcs in two radii. The red copper tube is a module made of double curves designed according to the drawings. The red copper tube is light in weight, good in rigidity and high in strength. The shapes of the red copper tubes processed are different and can be processed into various geometric shapes such as arcs and spheres. It is beautiful, then heat it, then place it on the mold prepared in advance, weld finally cut, fold, polish and polish it. The whole process needs to be very careful to ensure the surface quality of the copper tube. This forming method is very suitable for parts with small model and large arc change. When the model size is relatively large and complex, it can be considered to break it into small pieces for forming, and then splice it into large pieces. For such copper pipes, the cost is high and the production period is long. 2 Forming method of roll bending This method is to make some modifications on the roll bending machine, and change one of the shafts into a concave type and the other into a convex type. This method can form a regular copper tube like a sphere with a small processing range, exquisite workmanship and fashionable personality of the hyperboloid copper tube but it has great advantages for copper tubes with small radians. What problems should be paid attention to when designing the hyperboloid copper tube? Everyone knows that the design of the air conditioning copper tube is very important. To achieve the beautiful shape, first of all, the design is very critical. Some small copper tube companies are not mature enough in design and have not enough design experience, so they often have problems in design, Hyperbolic copper tube is very famous for preparing some details that we should pay attention to in the design. The sculpted copper tube is highly decorative, and the production and processing technology of hyperbolic shaped copper tube is relatively complex. Copper tube products with strong aesthetics. According to the design requirements, different shapes need to be molded for the sculpted copper tube, so the production process of sculpted aluminum veneer is relatively complex.

Corrosion of copper in humid air is a chemical reaction, which makes copper look ugly. The above operations will make copper tubes beautiful. Bright brass tubes are still common in today's daily life and will be used in many places. But even with such a common product, many people still do not understand its performance characteristics. So, what are the excellent performance characteristics of this product? Here is a brief introduction to this article.

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, adhere to the wear form condition simulation criteria of the sample test 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, 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.

Matosinos.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.

Attention shall be paid to the purchase of red copper pipe in order to study the distribution law of pipeline crack stress field under internal pressure. The simulation ysis and experimental verification are carried out for pipes with cracks of different shapes, different directions, different internal pressures and different sizes. The results show that the stress at the crack tip is much greater than that at the crack center. The crack shape has little effect on the stress. With the increase of the included angle between the crack direction and the pipe axis, the stress at the crack tip first increases and then decreases. With the increase of the pipe internal pressure, crack depth, and crack length, the stress at the crack tip increases linearly. Among them, the effect of crack length on the stress at the crack tip is smaller than that of internal pressure and crack depth. During the construction and operation of long-distance pipeline, due to the influence of pipe manufacturing defects, welding defects, internal and external loads, stress concentration, corrosion defects and other factors, the pipeline will produce cracks and expand cracks, which is the most dangerous defect of long-distance pipeline and the main reason for pipeline failure. At present, pipeline cracks are mainly determined by internal testing and non-destructive testing after excavation. Among them, ultrasonic internal testing has a good identification rate for cracks with a length of more than 25 mm, a depth of more than 1 mm in the base metal or a depth of more than 2 mm in the weld; Magnetic flux leakage internal detection has a certain detection rate for cracks with opening more than 0.25mm, but it is difficult to identify and quantify. In NDT, magnetic particle, penetration, eddy current and radiographic methods have high detection and identification rate. The generation and propagation of cracks will cause local stress concentration in the pipeline, which is prone to brittle fracture, fatigue damage, corrosion damage and other failure phenomena, seriously affecting the service performance and reliability of long-distance pipeline. In this paper, the influence of crack shape direction and size on the stress at the crack tip is yzed by studying the stress field distribution law of copper pipe cracks, which provides a reference for the prevention and control of pipe cracks. What problems will be encountered in the production of copper tubes. The production of copper pipe includes four steps: welding, forming, inspection and pipe expansion.

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, 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, 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, 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 surface may be oxide and oil and it can be lifted up and down three to four times. If the medical copper tube is not acid resistant, 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.