Shandong heat exchanger cleaning, heat transfer operation technology, chemical principle, the material that is not clean and easy to scale flows through the tube that is easy to clean, Shandong heat exchanger cleaning, heat transfer operation technology, chemical principle (1) the material that is not clean and easy to scale flows through the tube that is easy to clean, is easy to clean; (2) the tube side should be selected for the fluid that needs to increase the flow rate to improve the heat transfer coefficient; (3) corrosive fluid should go through the tube side to avoid the corrosion of tube bundle and shell at the same time; (4) for the fluid with high pressure, the tube side should be selected to prevent the shell from being compressed; (5) the steam goes through the shell side, and the condensate is easy to be discharged; (6) the cooled fluid generally goes through the shell side, which is convenient for heat dissipation; (7) when the viscosity is large and the flow rate is small, the shell side re > 100 can achieve turbulence. It is stipulated in the series of standards φ twenty-five × 2.5mm, φ nineteen × 2 mm. The cleaning steel pipe length of heat exchanger in Shandong Province is usually 6m. According to the national standard, there are four specifications of 1.5m, 2m, 3M and 6m, among which 3M and 6m * are the most common. There are two kinds of arrangement of heat exchange tubes: equilateral angular arrangement and square arrangement. Equilateral angular arrangement is more important than square arrangement in the selection of heat exchange tube specification and arrangement. For example, first consider the requirements of fluid pressure, corrosiveness and cleaning, and then consider meeting other requirements. The cleaning principle of heat exchanger in Shandong chemical industry is equilateral triangle and square. Equilateral triangle arrangement is more compact than square arrangement, but square arrangement is convenient for cleaning. Heat transfer is always from high temperature to low temperature. In chemical industry, the heat transfer process is realized by heat exchanger, and the application of inter wall heat exchanger is widely. The heat transfer process of cold and hot fluids through the inter wall includes three steps: heat is transferred from the hot fluid to the side of the inter wall and from the side of the inter wall to the other side; heat is transferred from one side of the inter wall to the other side** From the wall to the cold fluid. There are two basic ways of heat transfer in inter wall heat exchanger: heat conduction and convective heat transfer. 5、 Type selection of tubular heat exchanger (1) problems to be considered in type selection of tubular heat exchanger 1. Selection of flow space 2. Selection of flow rate heat transfer operation technology chemical engineering principle 3. Inlet of heating agent (or coolant) Methods to determine the outlet temperature 4. Selection of cleaning tube type 5. Single pass and multi pass 6. Tube specification 7. Calculation of fluid flow resistance (pressure drop) through the heat exchanger (2) selection steps of tubular heat exchanger 1. According to the heat exchange task, determine the flow rate of two fluids, inlet and outlet temperature, operating pressure, physical property data, etc. 2. Determine the structure of the heat exchanger and the flow space of the fluid in the heat exchanger. 3. Calculate the heat load, calculate the average temperature difference, select the total heat transfer coefficient, and preliminarily calculate the heat transfer area according to the basic heat transfer equation, which can be used as the basis for selecting the type of heat exchanger, and determine the actual heat transfer area s of the primary heat exchanger, The actual heat transfer area of the primary heat exchanger and the required heat transfer coefficient K are determined. 4. Pressure drop check 5. Calculate the total heat transfer system Shandong heat exchanger cleaning number 6. Calculate the heat transfer area s, and then compare with the actual heat transfer area s of the heat exchanger. If s / s needs to be between 1.1 ~ 1.25 (or K / k), it is considered reasonable. Otherwise, select another K, and repeat the above calculation steps until it meets the requirements（ 3） The basic parameters of tubular heat exchanger are: 1. Nominal heat exchange area Sn; 2; ② Nominal diameter DN; ③ Nominal pressure PN; ④ Specification of heat exchange tube; ⑤ Length of heat exchange tube L; ⑥ Number of tubes n; ⑦ Tube number NP; wait. The model of tubular heat exchanger consists of five parts. 123451 -- Code of heat exchanger; 2 -- Nominal Diameter DN, mm; 3 -- tube number NP, I, II, IV, VI; 4 -- nominal pressure PN, MPa; 5 -- nominal heat exchange area Sn, M2. From the basic equation of heat transfer rate q = Ka Δ T can be seen, heat transfer speed training: heat exchanger operation 1, heat transfer Shandong heat exchanger cleaning rate influence factors analysis of heat transfer operation technology chemical engineering principle from the basic equation of heat transfer rate Qka Δ TM shows that heat transfer rate is related to heat transfer area a and heat transfer temperature difference Δ Therefore, changing these factors will affect the heat transfer rate. 1. Increasing the heat transfer area can improve the heat transfer rate of the heat exchanger. However, increasing the heat transfer area can not be achieved by simply increasing the equipment specification, because it will increase the volume of the equipment, increase the metal consumption and increase the equipment cost. Practice has proved that starting from improving the structure of the equipment, increasing the heat transfer area per unit volume can make the equipment more compact and more reasonable. At present, the heat transfer operation technology and chemical principle heat transfer area can make the equipment more compact and more reasonable, The heat transfer area per unit volume is much larger than that of tube and tube heat exchanger. At the same time, we also developed and successfully used a variety of effective energy heat transfer surface, such as the heat transfer tube with warping plate, which is often used in the tube heat exchanger in engineering. It can not only increase the heat surface, but also strengthen the turbulence degree of fluid and improve the efficiency of heat transfer α， The heat transfer rate is significantly increased. 2. Increasing the average temperature difference of heat transfer can improve the heat transfer rate of heat exchanger. The average temperature difference of heat transfer depends on the temperature and flow pattern of the two fluids.