Veru2507 stainless steel plateOriented function

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, and the fracture line shall be inclined to the pivot of the plastic coated copper pipe. Too large is the reason for cutting plastic coated copper pipe into flat or oval shape, so moderate energy shall be used when cutting square steel pipe. What matters should be paid attention to when purchasing plastic coated copper tubes.

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,Veru304 stainless steel plate, the qualified products are pasted with protective film and bound with bubble film or wooden box.

Veru. Insert the pipe into the top of the bayonet, rotate the sleeve on the pipe to evenly apply the flux on the joint, then wipe off the excess flux, and the joint is assembled and can be heated.

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, 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, 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, but it cannot be transformed. Through experiments it can be found that there will be about 2% of retained austenite. At this time, 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, 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, they can only stand to eat and probably enjoy food in other places. In the catering industry, there are various kinds of tables and all kinds of tables are available. There are wooden tables and medical copper controlled tables. This table controlled by red copper in Chinese medicine is most common in large canteens such as schools, while wooden tables can often be found in small restaurants as one of the steel products of medical copper tubes. As his name is common, medical copper tubes have the ability to prevent rust. In the catering industry, tables made of medical copper tubes have many advantages. Next, the teacher of Medical Copper Tube Consumption Co., Ltd. will introduce you to the master. The medical copper tube table is easy to see in the large canteen. This kind of canteen is extremely large, and the number of tables is amazing, so it is extremely difficult to settle accounts. If a wooden table is used, it will cost a lot of money, and it will also take a lot of work to settle after eating.

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, 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, 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, t2 Medical Copper Tube Company revealed that Panbo consumers should carefully select according to the situation, 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, it has been widely used in food 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, 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, they can only stand to eat and probably enjoy food in other places. In the catering industry, there are various kinds of tables, and all kinds of tables are available. There are wooden tables and medical copper controlled tables. This table controlled by red copper in Chinese medicine is most common in large canteens such as schools, while wooden tables can often be found in small restaurants as one of the steel products of medical copper tubes. As his name is common, medical copper tubes have the ability to prevent rust. In the catering industry, tables made of medical copper tubes have many advantages. Next, the teacher of Medical Copper Tube Consumption Co., Ltd. will introduce you to the master. The medical copper tube table is easy to see in the large canteen. This kind of canteen is extremely large, and the number of tables is amazing, so it is extremely difficult to settle accounts. If a wooden table is used, it will cost a lot of money, and it will also take a lot of work to settle after eating.

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, so it is also called degreasing copper tube. In terms of conductivity and thermal conductivity, 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, because it can be applied to different aspects. As the conductivity of copper is better than aluminum, 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.

This week (23-2, the market price of red copper bar rose, and the transaction was not ideal. On the bidding day of Shagang last weekend, the price was stable to support the market, and the rising of billets at the weekend drove the market up in a wave, and the price of variety wire rods also rose by 50 yuan at the weekend. However, it was reported that the deal was very poor, which led to the price being stable for the next two days. Until Wednesday, due to the negative outlook on the future market and the reduction of steel billets in the afternoon spiral diving, Xinji rose 50 yuan on the 23rd; For the future market,VeruStainless steel welded pipe, the off-season is coming, the demand is weakening, and the market wait-and-see mood is getting stronger. But when winter comes, the environmental protection inspection is becoming more and more strict, which supports the market. It is expected that the price of variety wire rod will be adjusted in a weak way in the short term.

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, otherwise it will cause local hollowing of the insulation layer. How to protect the medical copper tube during installation? The medical copper pipe shall be installed in strict accordance with the installation requirements, 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.

Test conclusion.The copper tube warehouse of automobile air conditioner shall not be stacked with acid, alkali, salt, cement and other materials that are corrosive to steel. The air conditioning copper pipe is based on carbon structural steel. The phenomenon of torsional deformation of the 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, toughness and hardenability of the annealing steel.

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, otherwise it will cause local hollowing of the insulation layer. How to protect the medical copper tube during installation? The medical copper pipe shall be installed in strict accordance with the installation requirements, the construction process must be strictly required, and do not place heavy objects on the surface.

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, 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, t2 Medical Copper Tube Company revealed that Panbo consumers should carefully select according to the situation, and when selecting the planning and design staff,Veru201 stainless steel plate, they should have a full understanding of the appearance of t2 Medical Copper Tube. Since the birth of medical copper tube, it has been widely used in food, 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, 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, sizing process, cooling bed process, straightening 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.

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, 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.

Total quality management.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.

Air conditioning copper tube production technology Upward lead method: This production method is electrolytic copper after copper tube is directly melted.

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

Veru.In future work, try to protect the surface of the copper tube.

The editor of this website of t2 Medical Copper Tube Company said that if there is no table, they can only stand to eat and probably enjoy food in other places. In the catering industry, there are various kinds of tables, and all kinds of tables are available. There are wooden tables and medical copper controlled tables. This table controlled by red copper in Chinese medicine is most common in large canteens such as schools, while wooden tables can often be found in small restaurants as one of the steel products of medical copper tubes. As his name is common, medical copper tubes have the ability to prevent rust. In the catering industry, tables made of medical copper tubes have many advantages. Next, the teacher of Medical Copper Tube Consumption Co., Ltd. will introduce you to the master. The medical copper tube table is easy to see in the large canteen. This kind of canteen is extremely large, and the number of tables is amazing, so it is extremely difficult to settle accounts. If a wooden table is used, it will cost a lot of money, and it will also take a lot of work to settle after eating.

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, 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, t2 Medical Copper Tube Company revealed that Panbo consumers should carefully select according to the situation, 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, it has been widely used in food, 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, 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 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, 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, 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.