tube sheet

When purchasing tube sheets, careful consideration and comparison should be made to ensure the selection of the correct product for the intended application. Whether used in heat exchangers, boilers, or pressure vessels, tube sheets play a crucial role in the overall performance and efficiency of equipment. The following are some important factors to consider when selecting the appropriate tube sheet: Material Selection: The material of the tube sheet should be compatible with the fluid or gas flowing through the pipeline. Factors such as corrosion resistance, thermal conductivity, and mechanical properties should be considered. Common materials used for tube sheets include carbon steel, stainless steel, copper alloys, nickel alloys, aluminum alloys, and titanium.   Tube Arrangement: The tube sheet design should accommodate the desired tube arrangement, whether it's a triangular, square, or staggered pattern. The number and size of tube holes should be carefully specified to ensure proper tube fit and alignment. Thickness and Strength: The tube sheet should have adequate thickness and strength to withstand the operating conditions and pressures within the equipment. The required thickness should be determined according to engineering calculations and standards, based on diameter, material, and pressure ratings.   Weldability: If it is necessary to connect the tubes to the tube sheets by welding, the material should have good weldability. Some materials may require preheating or post weld heat treatment to maintain the integrity of the joint.   Cladding or Coating: In applications where corrosion resistance is crucial, in order to reduce the use of high corrosion-resistant materials for the whole tube sheet, the tube sheet can be coated or clad with a higher alloy material. This provides effective protection against corrosive fluids or environments and extends the service life of the tube plate. The materials used for coatings usually include stainless steel, nickel, titanium, etc.   Quality Assurance: It is important to purchase tube sheets from reputable manufacturers or suppliers who comply with industry standards and quality control processes. Wuxi Changrun has 30 years of production experience and supply flanges, tube sheets, for well-known petrochemical industry giants in various countries, including PetroChina and Sinopec, BASF, Bayer, Chevron, Mobil, etc.    Customization: In some cases, it may be necessary to customize the designed tube plate to meet specific project requirements. Collaborating with experienced engineers and manufacturers can help design and manufacture customized tube sheets. Wuxi Changrun has a professional team of engineers and technicians who can manufacture customized products according to customer needs.   It is recommended to consult with industry experts, engineering consultants, or equipment manufacturers to ensure that the selected forged tube sheet meets the desired performance and longevity requirements. By considering these factors, the right tube sheet can be chosen to enhance the overall efficiency and reliability of the equipment in which it is used. Get more details from www.wuxichangrun.com.

What is the function of overlay welded tube sheets?   In industrial applications, corrosion resistance and structural integrity are very important, and welded overlay tube sheets have become essential components. Overlay welding also known as cladding, is a process of coating a corrosion-resistant alloy on the surface of a based materials. This technology provides an effective solution to protect the tube sheet from the impact of corrosive environments and extends its service life. And it can greatly reduce costs.   The main purpose of overlay welding tube sheets is to improve the performance and durability of heat exchangers, boilers, and other equipment using tube sheets. The following are some main advantages and precautions related to overlay welded tube sheets:   Corrosion Resistance: By cladding a layer of corrosion-resistant alloy to the tube sheet's surface, the weld overlay layer protects against corrosion caused by corrosive fluids, high temperatures, or harsh operating conditions. This corrosion resistance helps to minimize maintenance requirements and maximizes the service life of the equipment. Common corrosion-resistant overlay metals include copper, titanium, nickel, cobalt based alloys, and austenitic stainless steel. For example, stainless steel overlay welding is used on the inner walls of petrochemical containers. When welding, workers should pay attention to the dilution rate of the based plate on the welding layer to ensure the alloy content required for corrosion resistance of the welding layer.   Material Compatibility: Weld overlay tube sheets allow for the selection of different materials for the base material and the cladding layer. This flexibility enables the use of cost-effective base materials while ensuring optimal corrosion resistance and compatibility with the process fluids or gases. The chemical composition of the welding material should be similar as the base materials to ensure that the welding layer has good corrosion resistance and wear resistance. The welding material should have sufficient strength and toughness to ensure the structural performance and durability of the welding layer. The overlay welding material should have good welding performance, including melting point, fluidity, wettability, etc. The welding material should have good crack resistance to ensure that the welding layer will not crack due to vibration and deformation during operation. The welding material should have a certain degree of wear resistance to ensure that the welding layer does not excessively wear during operation.   Enhanced Strength and Integrity: Weld overlay also improves the mechanical properties of forged tube sheet, including strength and toughness. It has higher hardness and wear resistance, and can withstand longer periods of wear and impact. The cladding layer adds an extra level of protection and reinforcement to the base material, reducing the risk of failure or leakage during operation.   Customization and Precision: Weld overlay tube sheets can be tailored to specific project requirements, such as the size and pattern of the tube holes, the thickness and composition of the cladding layer, and the welding techniques used. This customization allows for precise fitting and dependable performance in various applications.   When selecting weld overlay tube sheets, several factors should be considered:   1.Corrosion Environment: Assess the nature of the operating environment, including the temperature, pressure, and the types of fluids or gases being processed. This information helps determine the appropriate corrosion-resistant alloy for the cladding layer.   2. Base Material Compatibility: Consider the compatibility between the base material and the cladding layer to ensure optimal bonding and long-term performance.    3. Cladding Thickness: Determine the appropriate thickness of the cladding layer based on the severity of the corrosion environment and the desired service life of the equipment.   4. Manufacturing Standards: Verify that the weld overlay tube sheets comply with relevant industry standards and quality assurance processes to ensure their reliability and performance.   In summary, weld overlay tube sheets play a crucial role in enhancing the corrosion resistance and durability of heat exchangers, boilers, and other equipment. The careful selection of materials, customization options, and adherence to manufacturing standards are key considerations when choosing weld overlay tube sheets for optimal performance and long-term reliability. https://www.wuxichangrun.com/

What is condenser? The condenser is one of the main heat exchange equipment in refrigeration equipment. The function of the condenser is to cool and condense the high-temperature and high-pressure refrigerant discharged from the compressor into liquid. The heat released by the refrigerant in the condenser is carried away by the cooling medium (water or air).   What is condenser Tube Sheet? The condenser tube sheet is a component of heat exchange in various industries, including power plants, chemical plants, refrigeration systems, and HVAC (Heating Ventilating and Air Conditioning). Its main function is to provide safe connections for the condenser tubes and promote effective heat transfer. Therefore, the working state of the condenser tube sheet directly affects the performance and efficiency of the condenser. Let's explore in more detail the importance and application of condenser tube sheets.   In power plants Firstly, condenser tube sheets are crucial in power plants, where they play a vital role in converting steam into water and facilitating the generation of electricity. The tube sheets offer structural support for the condenser tubes, allowing the transfer of heat from the steam to the cooling medium, typically water. This heat transfer process is essential for converting high-pressure steam into liquid water, which can then be recycled and reused in the power generation cycle.   In chemical plants In chemical plants, condenser tube sheets are used for various purposes, such as cooling and condensing volatile substances, recovering valuable chemicals or solvents, and facilitating heat exchange in chemical processes. The tube sheets provide a stable platform for the condenser tubes, ensuring efficient heat transfer and enabling the separation and collection of desired substances from gas or vapor streams.   In refrigeration systems Condenser tube sheets also find application in refrigeration systems, where they aid in the cooling and condensation of refrigerants. These systems rely on the expansion and compression of refrigerants to transfer heat from the conditioned space to the surrounding environment. The condenser tube sheets help facilitate this heat transfer process by providing a surface for the refrigerant to release heat, enabling its transition from a high-pressure vapor to a low-pressure liquid state.   In HVAC In HVAC (Heating, Ventilation and Air Conditioning) systems, condenser tube sheets are utilized in air-cooled condensers. These systems use the condenser tube sheets to support the tubes through which the refrigerant flows. As the refrigerant releases heat to the ambient air, it condenses into a liquid state before flowing back to the evaporator, enabling the cooling and conditioning of indoor spaces.   The material of condenser tube sheets To ensure the effective functioning of condenser tube sheets, proper material selection is essential. Factors such as corrosion resistance, strength, and thermal conductivity play a significant role in determining the suitable material for the tube sheet. Stainless steel, carbon steel, copper alloys, and titanium are commonly utilized due to their excellent corrosion resistance and mechanical properties.   Regular inspection and maintenance of condenser tube sheets are critical to identify any signs of corrosion, erosion, or leaks. Timely repairs or replacements can prevent system failures and ensure prolonged operational efficiency.   In conclusion, wuxichangrun condenser tube sheets are essential components in various industries, enabling efficient heat transfer, condensation, and cooling processes. Their proper selection, installation, and maintenance are crucial to maintaining optimal system performance, energy efficiency, and reliability.

Tube sheet refers to the plate used for supporting and protecting pipelines. Pipelines are usually connected to the tubesheet through mechanical fixation or welding after drilling. In addition to serving as a fixing function, the pipe plate can also withstand the fluid and pressure inside the pipeline, reducing vibration and damage during operation. Carbon steel tube sheet, as a common tube sheet material, has a wide range of applications.     Carbon steel tube sheets are mainly composed of iron and carbon, which contain a high proportion of carbon elements, usually between 0.2% and 2.1%. In addition, it may also contain small amounts of elements such as manganese, silicon, and phosphorus, which can improve the strength and corrosion resistance of carbon steel plates. Here are some main advantages and disadvantages of carbon steel pipe sheets:   Advantages: 1. High cost-effectiveness: Carbon steel, as a common and economical material, is more affordable compared to other high alloy materials, making carbon steel pipe sheets the preferred choice in many applications.   2. High strength: Carbon steel is a type of steel with high strength, and its tensile strength is usually between 400-550MPa. This enables carbon steel plates to have high strength and rigidity under heavy loads and high pressures, enabling carbon steel pipe plates to maintain stability and reliability in high temperature and high pressure environments.   3. Good wear resistance: Carbon steel plates can achieve higher hardness and good wear resistance after heat treatment. Therefore, in some situations where wear resistance is required, carbon steel plate is the preferred material.   4. Easy to process and weld: Due to its low carbon content, carbon steel plates have good plasticity and weldability, and can be processed through various methods such as cold processing and hot processing. This makes the manufacturing and installation process of carbon steel pipe sheets relatively simple and efficient, reducing production costs and time.   5. Good environmental performance: Compared to other materials, carbon steel plates have better environmental performance. It can be recycled and reused to reduce resource waste and also reduce environmental pollution.         Disadvantages: 1. Easy to corrode: Carbon steel plates are prone to rusting, which is one of their biggest drawbacks. Due to the high content of iron in carbon steel plates, rust will occur when they react with oxygen in the air. This not only affects the appearance, but also leads to corrosion and damage to the surface of the board. Compared to stainless steel and other high alloy materials, carbon steel is more prone to corrosion in corrosive environments such as humidity, acidity, and alkalinity, which may lead to damage and shortened lifespan of the tube plate. To address corrosion issues, surface coatings or the use of anti-corrosion coatings can be used to enhance the corrosion resistance of carbon steel pipe sheets.   2. Not suitable for high temperature and strong acid environments: Carbon steel has lower temperature and acid resistance than high alloy materials, so in some applications that require high temperature or acidic media, carbon steel pipe sheets may not be suitable. This drawback can be avoided by welding other alloy materials to alter the performance of the contact surface.   3. Heavy weight: Compared to some lightweight alloy materials, carbon steel pipe sheets are relatively heavy, which may increase installation and maintenance difficulties.     In summary, carbon steel pipe sheets have advantages such as high cost-effectiveness, high strength, and ease of processing. However, their corrosion resistance, temperature resistance, and weight need to be evaluated based on specific application environments, and suitable materials should be selected to meet the requirements.

Tube sheets are mainly used in chemical containers, such as heat exchangers, pressure vessels, boilers, condensers, central air conditioning, evaporators, and seawater desalination, to support and fix the column pipes. The metal material not only makes them highly rigid, but also has great thermal conductivity. There are different types of tube plates, each designed for specific applications. The following are some common types of tube sheets and their specific explanations:     1.Floating tube sheet Floating tubesheets are an important component of floating head heat exchangers. It plays a stabilizing role by being installed inside the floating head heat exchanger and supporting the structure of the tube bundle. When the tube bundle is subjected to the impact of the working medium and the pressure flowing through the tube bundle, the floating tubesheet will play a supporting role in preventing the vibration of the tube bundle, thereby ensuring the smooth flow of the medium and the safety inside the heat exchanger. During the operation of the heat exchanger, the tube bundle will expand due to heating and contract after cooling. This kind of thermal expansion and contraction will generate huge stress on the tube bundle, which is prone to cracking and deformation. The floating tube sheet can move up and down, allowing the tube bundle to freely expand and contract with temperature changes, thereby offsetting the stress generated by the tube bundle. Avoiding fatigue damage and leakage of the tube bundle can increase the fluid dynamic interaction between the tube bundle and the shell, and improve the heat transfer efficiency of the heat exchanger. Floating tube sheets are widely used in various types of heat exchangers, especially in fluids with high convective heat transfer coefficients, and their effects are more pronounced. When designing a heat exchanger, parameters such as the length, width, thickness, and floating rod length of the floating tube plate need to be selected according to specific circumstances to ensure the stability and efficiency of the heat exchanger.     2. Fixed tube sheet Fixed tube sheet also known as tube fixing fixture. It is a device used to fix and protect pipeline systems. It can ensure the stability and safety of pipeline systems. It is usually used to fix tube plate heat exchangers, and the two end tube plates are connected and fixed to the shell by welding. The structural feature is that a tube bundle is installed in the shell, and the two ends of the tube bundle are fixed on the tube plate through welding or expansion joint. The tube plates at both ends are directly welded to the shell, and the inlet and outlet pipes on the shell side are directly welded to the shell. The flange at the outer edge of the tube plate head is fastened with bolts, and the inlet and outlet pipes on the tube side are directly welded to the head. Several baffles are set inside the tube bundle according to the length of the heat exchange tube. The tube side of the heat exchanger can be divided into any number of channels through a diaphragm.   Fixed tube sheet heat exchangers have the advantages of simple structure, low manufacturing cost, convenient cleaning, multiple tube passes, double shell passes, and wide specification range, and have been widely used in engineering. It is difficult to clean the shell side. Not suitable for dirty or corrosive media. If the expansion difference is large, we can install an expansion joint on the shell to reduce the thermal stress caused by the temperature difference on the shell side. It has the advantages of small bypass seepage, less use of forgings, low cost, no internal leakage, and a heat transfer volume 20%~30% larger than that of floating head heat exchangers.    

A CNC machined tube plate refers to a tube sheet or plate that has undergone precision machining using a Computer Numerical Control (CNC) machine.  CNC machining involves the use of computer numerical control to automate and control the movement of machining tools and equipment. This technology allows for precise and accurate shaping, cutting, and drilling of materials, including metal plates used in various applications.   Information on CNC machining tube plates 1. Tube Sheet in Heat Exchangers: In the context of heat exchangers, a tube sheet is a plate that separates the fluid in the tubes from the fluid in the shell of the heat exchanger. CNC machining can be used to create precise holes in the tube sheet for the tubes to pass through.   2. CNC Tube Cutting: This could refer to the process of using CNC machines to cut tubes into specific lengths or shapes. CNC tube cutting is commonly used in industries such as automotive, aerospace, and construction.   3. Tube Plate in Structural Engineering: In structural engineering, a tube plate might be a component used in the construction of steel structures, such as trusses or frames. CNC machining can be employed to create precise cuts and holes in these plates.     CNC machining tube plate 1. Hole Drilling: CNC machines can accurately drill holes in tube plates to accommodate tubes in heat exchangers or other systems. The hole patterns need to be precisely designed to ensure proper alignment and fit.   2. Milling and Cutting: CNC milling machines can be employed to cut and shape tube plates according to specific designs and requirements. This can include creating intricate patterns or features on the surface of the tube plate.   3. Surface Finishing: CNC machining can be used to achieve a smooth and precise finish on the surface of the tube plate. This is important for both functional and aesthetic reasons, depending on the application.   4. Customization: CNC machining allows for a high level of customization. Tube plates can be machined to exact specifications, accommodating different sizes, hole patterns, and materials based on the requirements of the specific application.     CNC machined tube plates are commonly used in the construction of heat exchangers, boilers, and similar equipment where precise alignment and secure attachment of tubes are essential for efficient heat transfer. The use of CNC machining ensures the production of high-quality, accurate, and repeatable tube plates in various industrial settings.    Relying on the top processing equipment cluster, wuxi changrun can provide multiple processes from material to cutting, beveling, welding, heat treatment, vertical turning, drilling and so on; Capable of processing tube plates and folding plates made of diversified materials such as pure titanium, stainless steel composite, high-specification stainless steel and various high-strength steels.

What is heat exchanger baffle? A heat exchanger baffle is a plate or barrier that is inserted into a heat exchanger to enhance heat transfer efficiency. The primary function of a baffle is to direct the flow of fluid inside the heat exchanger in a specific pattern, such as cross-flow or counter-flow, to maximize heat transfer.   Baffles are commonly used in shell and tube heat exchangers, which consist of a bundle of tubes enclosed in a shell. The baffles are placed inside the shell, perpendicular to the tube bundle, and divide the shell into several chambers. The fluid flows through the tubes and is directed by the baffles through each chamber, which increases the time the fluid spends in contact with the tube surface, thereby enhancing heat transfer efficiency.       The types of baffle plates The design and placement of baffles in a heat exchanger depend on the specific application requirements, including the type of fluid being heated or cooled, the flow rate, temperature, and pressure, and the desired heat transfer rate. The size, shape, and thickness of the baffles may also vary depending on the application. The baffle plate is installed on the shell side, which can not only improve heat transfer efficiency but also play a role in supporting the tube bundle. There are two types of baffles: arched and disc-shaped. Arched baffles are available in three types: single arched, double arched, and triple arched.     What is the function of a baffle? 1. Extend the flow channel length of the shell side medium, increase the flow velocity between tubes, increase the degree of turbulence, and achieve the goal of improving the heat transfer efficiency of the heat exchanger.   2. Setting baffle plates has a certain supporting effect on the heat exchange tubes of horizontal heat exchangers. When the heat exchange tube is too long and the pressure stress borne by the tube is too high, increasing the number of baffle plates and reducing the spacing between baffle plates while meeting the allowable pressure drop of the heat exchanger tube side can play a certain role in alleviating the stress situation of the heat exchange tube and preventing fluid flow induced vibration.   3. Setting baffle plates is beneficial for the installation of heat exchange tubes.       Heat exchange baffles can be made of various materials, such as stainless steel baffle plates, carbon steel baffle plates, or titanium baffle plates, depending on the corrosive or erosive nature of the fluid being processed. In some cases, baffles may also have holes or slots to allow for more fluid flow and heat transfer.   Wuxi Changrun has provided high-quality baffle plate, tube sheets, nozzles, flanges, and customized forgings for heat exchangers, boilers, pressure vessels, etc. to many well-known petrochemical enterprises at home and abroad. Our customers include PetroChina, Sinopec, Chevron, Bayer, Shell, BASF, etc. Send your drawings to sales@wuxichangrun.com We will provide you with the best quotation and the highest quality products.  

1. Theoretical basis for tube sheet calculation   The structure of shell and tube heat exchangers is complex, and there are many factors that affect the strength of the tube sheet. In particular, the tube sheet of fixed tube sheet heat exchangers is subjected to the most complex force. The design specifications of various countries basically consider the tube sheet as a circular flat plate that bears uniformly distributed loads, is placed on an elastic foundation, and is uniformly weakened by the tube holes (Figure 1).   Due to the many factors that affect the strength of the tube sheet, it is difficult and complex to accurately analyze the strength of the tube sheet. Therefore, various countries simplify and assume the formula for calculating the thickness of the tube sheet to obtain an approximate formula.   The loads that cause stress on the tube sheet include pressure (tube side pressure Pt, shell side pressure Ps), thermal expansion difference between the tube and shell, and flange torque. The mechanical model of the calculation method for the tube sheet of the heat exchanger is shown in Figure 2.   1.1 The design specifications of various countries consider the following factors to varying degrees for the tube sheets: 1) Simplifying the actual tube sheet into a homogeneous equivalent circular flat plate based on equivalent elasticity weakened by regular arrangement of tube holes and reinforced by tubes has been adopted by most countries' tube plate specifications today. 2) The narrow non piping area around the tube sheet is simplified as a circular solid plate based on its area. 3) The edge of the tube sheet can have various types of connection structures, which may include shell side cylinders, channel cylinders, flanges, bolts, gaskets, and other components. Calculate according to the actual elastic constraint conditions of each component on the edge of the tube sheet. 4) Consider the effect of flange torque on the tube sheet. 5) Consider the temperature difference stress caused by the thermal expansion difference between the heat exchange tube and the shell side cylinder, as well as the temperature stress caused by the temperature difference at various points on the tube sheet. 6)Calculate various equivalent elastic constants and strength parameters converted from porous plates with heat exchange tubes to equivalent solid plates.     1.2 Theoretical basis for GB151 tube sheet calculation The mechanical model considers the tube plate as an axial symmetry structure and assumes that the tubesheets at both ends of the heat exchanger have the same material and thickness. For fixed tube sheet heat exchangers, the two tube sheets should also have the same boundary support conditions.   1) The supporting effect of tube bundle on tube sheet Consider the tube sheet as an equivalent circular flat plate uniformly weakened and placed on an elastic foundation. This is because in the structure of shell and tube heat exchangers, the diameter of the majority of tubes is relatively small compared to the diameter of the tube sheet, and the number of tubes is sufficient. It is assumed that they are uniformly distributed on the tube sheet, so the support effect of each discrete heat exchange tube on the tube sheet can be considered uniform and continuous, and the load borne by the tube sheet is also considered uniformly distributed.   The tube bundle has a restraining effect on the deflection and rotation angle of the tube sheet under external loads. The restraining effect of the tube bundle can reduce the deflection of the tube sheet and lower the stress in the tube sheet. The tube bundle has a restraining effect on the angle of the tube sheet. Through analysis and calculation of actual parameters, it was found that the restraining effect of the tube bundle on the angle of the tube sheet has a very small impact on the strength of the tube sheet and can be completely ignored. Therefore, this   The specification does not consider the constraint effect of tube bundles on the corner of the tube sheet, but only considers the constraint effect of tube bundles on the deflection of the tube sheet. For fixed tube sheet heat exchangers, the tube reinforcement coefficient K is used to represent the tube sheet.   The bending stiffness of the perforated tube plate is η D The elastic foundation coefficient N of the tube bundle represents the pressure load required to be applied on the surface of the tube plate to cause unit length deformation (elongation or shortening) of the tube bundle in the axial direction.   the pipe reinforcement coefficient K and substitute it into the expressions D and N, so that ν P=0.3: This coefficient indicates the strength of the elastic foundation relative to the tube plate's inherent bending stiffness, reflecting the enhanced load-bearing capacity of the tube bundle on the plate. It is a crucial parameter that characterizes the strengthening effect of the tube bundle on the plate. If the elastic foundation of the plate is weak, the enhancing effect of the heat exchange tubes is minimal, resulting in a small K value. Consequently, the plate's deflection and bending moment distribution resemble those of ordinary circular plates lacking an elastic foundation. Specifically, when K equals zero, the plate becomes an ordinary circular plate. Based on the theory of elastic foundation circular plates, the plate's deflection is not solely determined by the tube's strengthening coefficient K, but also by its peripheral support and additional loads, quantitatively represented by the total bending moment coefficient m.   When the periphery of the tube sheet is simply supported, MR=0, then m=0; When the periphery of the tube sheet is fixed, the corner of the edge of the tube sheet φ R=0, from which a specific value of m can be obtained (the expression is omitted); When the periphery of the tube plate only bears the action of bending moment, i.e. VR=0, then m=∞. Under certain boundary support conditions, as the K value gradually increases, the deflection and bending moment of the tubesheet exhibit a attenuation and wavy distribution from the periphery to the center. The larger the K value, the faster the attenuation and the more wave numbers. During the process of increasing K value, when passing through a certain boundary K value, new waves will appear in the distribution curve. At the center of the plate, the curve changes from concave (or concave) to concave (or concave). Solving the derivative equation of the distribution curve can obtain the K boundary value of the curve with an increase in wave number.   Taking the simple support around the tube sheet as an example, as the strengthening coefficient K of the tube increases, the radial bending moment distribution curve and the boundary K value when new waves appear are shown in Figure 31. At the same time, it can be seen that the radial extreme value also moves away from the center of the tube sheet towards the periphery as the K value increases.   For the elastic foundation plate with peripheral fixed support, the radial bending moment distribution shows a similar trend with the change of K value, as shown in Figure 3. The difference from a simply supported boundary is that the maximum radial bending moment of the elastic foundation plate supported by a fixed boundary is always located around the circular plate, while the extreme point of the second radial bending moment moves away from the center of the plate and towards the periphery as K increases.   For floating head and filled box heat exchanger tube sheets, the modulus K of the tube bundle is similar to the elastic foundation coefficient N of the fixed tube sheet, which also reflects the strengthening effect of the tube bundle as an elastic foundation on the tube sheet.   2) The weakening effect of tube holes on tube sheets The tube sheet is densely covered with dispersed tube holes, so the tube holes have a weakening effect on the tube sheet. The weakening effect of tube holes on the tube sheet has two aspects:   The overall weakening effect on the tube sheet reduces both the stiffness and strength of the tube sheet, and there is local stress concentration at the edge of the tube hole, only considering peak stress.   This specification only considers the weakening effect of openings on the overall tube sheet, calculates the average equivalent stress as the basic design stress, that is, approximately considers the tube sheet as a uniformly and continuously weakened equivalent circular flat plate. For local stress concentration at the edge of the tube hole, only peak stress is considered. But it should be considered in fatigue design.   The tube hole has a weakening effect on the tube sheet, but also considers the strengthening effect of the pipe wall, so the stiffness weakening coefficient is used η And strength weakening coefficient μ。 According to elastic theory analysis and experiments, this specification stipulates η and μ＝ 0.4.   3) Equivalent diameter of tube sheet layout area The calculation of the reinforcement coefficient for fixed tube sheets assumes that all pipes are uniformly distributed within the diameter range of the cylinder. In fact, under normal circumstances, there is a narrow non pipe area around the tube sheet, which reduces the stress at the edge of the tube sheet.   The tube layout area is generally an irregular polygon, and now the equivalent circular pipe layout area is used instead of the polygonal pipe layout area. The value of the equivalent diameter Dt should make the supporting area of the tube on the tube sheet equal. The diameter size directly affects the stress magnitude and distribution of the tube plate. In the stress calculation of the fixed tube sheet in GB151, the stress located at the junction of the annular plate and the pipe layout area is approximately taken as the stress of the full pipe layout tube plate at a radius of Dt/2. Therefore, the standard limits this calculation method to only be applicable to situations where the non pipe layout area around the tube plate is narrow, that is, when the non dimensional width k of the non pipe layout area around the tube sheet is small, k=K (1)- ρ t) ≤ 1.   Whether it is a fixed tube sheet heat exchanger, or a floating head or filled box heat exchanger, when calculating the area of the tube layout area, it is assumed that the tubes are uniformly covered within the range of the tube layout area.   Assuming there are n heat exchange tubes with a spacing of S. For a triangular arrangement of tube holes, the supporting effect of each tube on the tube sheet is the hexagonal area centered on the center of the tube hole and with S as its inner tangent diameter, i.e;   For tubes with square arrangement of tube holes, the supporting area of each tube on the tube sheet is a square area centered on the center of the tube hole and with S as the side length, i.e. S2.   The tube sheet layout area is the area enclosed by connecting the supporting area of the outermost tube of the tube sheet, including the supporting area of the outermost tube itself.   For a single pass heat exchanger tube sheet with uniformly distributed heat exchange tubes, the supporting area of all n heat exchange tubes on the tube sheet is the area of the tube layout area.   4) Consider the bending effect of the tube sheet, as well as the tensile effect of the tube sheet and flange along their central plane.   5) Assuming that when the flange deforms, the shape of its cross-section remains unchanged, but only the rotation and radial displacement of the center of gravity around the ring section. Due to this rotation and radial displacement, the radial displacement at the connection point between the flange and the center surface of the tube sheet should be coordinated and consistent with the radial displacement along the center surface of the tube sheet itself.   6) Due to temperature expansion difference γ The axial displacement of the shell wall caused by the shell side pressure ps and the tube side pressure pt should be coordinated and consistent with the axial displacement of the tube bundle and tube sheet system around the tube sheet.   7) The corner of the tube sheet edge is constrained by the shell, flange, channel, bolt, and gasket system, and its corner should be coordinated and consistent at the connection part.   8) When the tube sheet is also used as a flange, the influence of flange torque on the stress of the tube sheet is considered. In order to ensure sealing, it is stipulated that the flange stress needs to be checked for the extended part of the tube sheet that also serves as a flange. At this time, when calculating the flange torque, it is considered that the tube sheet and flange jointly bear the external force moment, so the ground force moment borne by the flange will be reduced.     About us Wuxi Changrun has provided high-quality tube sheets, nozzles, flanges, and customized forgings for heat exchangers, boilers, pressure vessels, etc. to many well-known petrochemical enterprises at home and abroad. Our customers include PetroChina, Sinopec, Chevron, Bayer, Shell, BASF, etc. Send your drawings to sales@wuxichangrun.com We will provide you with the best quotation and the highest quality products.  

904L alloy steel has the following characteristics: 904L is a highly alloyed austenitic stainless steel with low carbon content. This steel is designed for environments with harsh corrosion conditions. Initially, this alloy was developed for corrosion resistance in dilute sulfuric acid. This feature has been proven to be very successful through years of practical application. 904L has been standardized in many countries and has been approved for use in the manufacture of pressure vessels. 904L alloy, like other commonly used CrNi austenitic steels, has good resistance to pitting and crevice corrosion, high resistance to stress corrosion cracking, good resistance to intergranular corrosion, good processability, and weldability. The maximum heating temperature during hot forging can reach 1180 degrees Celsius, and the minimum stop forging temperature is not less than 900 degrees Celsius. This steel can be hot formed at 1000-1150 degrees Celsius. The heat treatment process of this steel is 1100-1150 degrees Celsius, and it is rapidly cooled after heating. Although this steel can be welded using universal welding processes, the most appropriate welding methods are manual arc welding and tungsten inert gas arc welding. When using manual arc welding to weld plates with a diameter not exceeding 6mm, the diameter of the welding rod shall not exceed 2.5mm; When the plate thickness is greater than 6 millimeters, the diameter of the welding rod is less than 3.2 millimeters. When heat treatment is required after welding, it can be done by heating at 1075-1125 degrees Celsius and then rapidly cooling. When using tungsten inert gas arc welding, the filler metal can be used with the same welding rod. After welding, the weld seam must be pickled and passivated.     904L metallographic structure 904L is a completely austenitic structure, and compared to austenitic stainless steels with high molybdenum content, 904L is not sensitive to the precipitation of ferrite and alpha phase.     Corrosion resistance of 904L Due to the low carbon content of 904L (maximum 0.020%), there will be no carbide precipitation under general heat treatment and welding conditions. This eliminates the risk of intergranular corrosion that occurs after general heat treatment and welding. Due to its high chromium nickel molybdenum content and the addition of copper, 904L can be passivated even in reducing environments such as sulfuric acid and formic acid. The high nickel content results in a lower corrosion rate even in the active state. In pure sulfuric acid with a concentration range of 0-98%, the usage temperature of 904L can reach up to 40 degrees Celsius. In pure phosphoric acid with a concentration range of 0-85%, its corrosion resistance is very good. Impurities have a strong impact on the corrosion resistance of industrial phosphoric acid produced by wet process technology. Among all types of phosphoric acid, 904L has better corrosion resistance than ordinary stainless steel. In highly oxidizing nitric acid, 904L has lower corrosion resistance compared to high alloyed steel grades without molybdenum. In hydrochloric acid, the use of 904L is limited to lower concentrations of 1-2%. Within this concentration range. The corrosion resistance of 904L is better than that of conventional stainless steel. 904L steel has high resistance to pitting corrosion. Its resistance to crevice corrosion is also very good in chloride solutions. The high nickel content of 904L reduces the corrosion rate in pits and crevices. Ordinary austenitic stainless steel may be sensitive to stress corrosion in an environment rich in chloride at temperatures above 60 degrees Celsius. By increasing the nickel content of the stainless steel, this sensitization can be reduced. Due to its high nickel content, 904L exhibits high resistance to stress corrosion cracking in chloride solutions, concentrated hydroxide solutions, and environments rich in hydrogen sulfide.     904L Tube sheet  A 904L tube sheet is a component used in various industrial applications particularly in heat exchangers and condensers. The 904L stainless steel tube sheet is specifically chosen for its superior resistance to aggressive environments, such as those containing sulfuric acid, phosphoric acid, and chloride solutions. It offers exceptional resistance to pitting, crevice corrosion, and stress corrosion cracking, making it highly suitable for applications in the chemical, petrochemical, and offshore industries. The use of 904L stainless steel tube sheets ensures the long-term reliability and performance of heat transfer equipment. Its corrosion resistance properties allow for extended service life and reduced maintenance requirements, resulting in cost savings and enhanced operational efficiency. Choose 904L tube sheets for superior corrosion resistance and reliable performance in demanding environments. Experience the benefits of this high-quality stainless steel alloy for your heat exchangers and condensers.     904L flange 904L flanges are commonly used in industries such as chemical processing, petrochemical, pharmaceutical, and offshore applications. Their resistance to corrosion makes them suitable for handling corrosive fluids and gases. Additionally, 904L flanges offer excellent strength, durability, and weldability, making them a reliable choice for critical applications. The use of 904L flanges can help ensure the integrity and longevity of piping systems by providing a robust and corrosion-resistant connection. They are available in various types, including slip-on, weld neck, blind, and threaded flanges, to suit different installation requirements. In summary, 904L flanges are specifically made from 904L stainless steel, which offers superior corrosion resistance in demanding environments. Their use can enhance the reliability and performance of piping systems, making them ideal for applications where corrosion resistance is paramount.   904L application areas: 904L alloy is a versatile material that can be applied in many industrial fields: 1. Petroleum and petrochemical equipment, such as reactors in petrochemical equipment. 2. Storage and transportation equipment for sulfuric acid, such as heat exchangers. 3. The flue gas desulfurization device in power plants is mainly used in the tower body, flue, door panels, internal components, spray systems, etc. of the absorption tower. 4. Scrubbers and fans in organic acid treatment systems.     Similar grades GB/T UNS AISI/ASTM ID W.Nr 00Cr20Ni25Mo4.5Cu N08904 904L F904L 1.4539     904L chemical composition C Si Mn P S Cr Ni Mo Cu Fe 0.02 1 2 0.045 0.035 19-23 23-28 4-5 1-2       Mechanical properties Tensile strength Yield Strength Elongation Density Melting point RmN/mm Rp0.2N/mm A5％ 8.0g/cm3 1300-1390℃       Wuxi Changrun has provided high-quality tube sheets, nozzles, flanges, and customized forgings for heat exchangers, boilers, pressure vessels, etc. to many well-known petrochemical enterprises at home and abroad. Our customers include PetroChina, Sinopec, Chevron, Bayer, Shell, BASF, etc. Send your drawings to sales@wuxichangrun.com We will provide you with the best quotation and the highest quality products.