China Zhejiang Huier Coating Environmental Protection Equipment Co., Ltd Company News

For advanced equipment such as spraying machines, it not only improves the efficiency of our spraying operations, but also makes the spraying more uniform and beautiful. Knowledge of usage is essential, and any device may experience minor malfunctions during use. Therefore, it is necessary to have knowledge of maintenance. Here, we have provided various considerations and methods for usage and maintenance, as follows:   usage method:   1. For materials that have already been sprayed, they should be covered and the spraying equipment used should not collide with protective facilities.   2. For various pipelines, it is necessary to wrap the pipe opening before spraying.   3. When spraying edges such as doors and windows, it is important to cover them.   Remember to block the area that needs to be blocked before using the sprayer, otherwise the previous completed project will be in vain.   Repair method:   For equipment failures, they are inevitable during use, but as long as you know how to self repair after a failure occurs, it is easy to solve and eliminate the problem.   Fault 1: Automatic paint spraying machine does not spray oil   Exclusion method:   1. Check whether the oil pump is pumping oil, whether the air pressure and oil pressure valve are adjusted to a certain pressure, whether the oil circuit is blocked and cleaned;   2. Is the spray gun start switch high enough, and does the top pin of the spray gun pop up when pressed to start; If the oil still does not come out, clean the inside and cap of the spray gun, and be careful not to immerse the spray gun oil seal in corrosive liquids such as toluene to prevent deformation and damage   Fault 2: The automatic paint spraying line conveyor does not move   Exclusion method:   1. Check if the frequency converter is started and if the parameters are correct;   2. Whether the chain is stuck or broken;   3. Is the motor running and is the overload protection switch reset   Fault 3: The robotic arm of the automatic spraying line does not move   Exclusion method:   1. Check if there is an alarm signal on the robotic arm, and ask professional maintenance personnel to solve the problem based on the alarm signal;   2. Press the robotic arm again to return to the origin and observe whether it returns to the origin and is in a normal state;   3. Loosen the wire end of the servo motor of the robotic arm and re plug it tightly;   4. Please notify the manufacturer for repair when the servo motor malfunctions.

In the production process of spray painting and baking paint for some products, there will be a large amount of process exhaust emissions, which pose a significant threat to the natural environment and the health of operators. Specifically, processes such as spray painting and baking require the use of a large amount of volatile compounds such as benzene, toluene, ethylbenzene, and ethyl acetate as coating solvents and diluents. These organic solvents will not adsorb onto the surface of the workpiece during spraying, but will evaporate completely into the air and become organic waste gas. These exhaust gases have characteristics such as low boiling point and easy volatilization at room temperature, which have a significant impact on the surrounding environment and the health of operators.   The content of volatile organic compounds in the air of some large cities in China is several times higher than that of cities in the United States, and the organic waste gas emitted from industrial production has become the main factor of urban air pollution in China. When these gases evaporate, they produce irritating odors that pose a great threat to the health of operators. Short term exposure can cause nausea, dizziness, and damage to the internal organs and nervous system of the human body when absorbed in large quantities. Therefore, in industrial production activities, in addition to adopting necessary protective measures, it is also necessary to avoid the emission of organic waste gas as much as possible and comprehensively collect and purify organic waste gas.   1 Basic principle   This scheme uses honeycomb shaped activated carbon as an adsorbent, and achieves the goal of air purification by adsorbing, purifying, desorbing, regenerating, and concentrating volatile organic compounds (VOCs), as well as catalytic combustion. The high air volume and low concentration organic waste gas are adsorbed by honeycomb shaped activated carbon to achieve the goal of air purification. After saturation of activated carbon adsorption, the activated carbon is regenerated by hot air desorption. The concentrated organic matter obtained by desorption is sent to the catalytic combustion bed for catalytic combustion, and the internal organic matter is oxidized into harmless CO2 and H2O. The hot exhaust gas after combustion is heated by a heat exchanger to produce cold air. After heat exchange, the cooled gas is partially discharged and partially used for the desorption and regeneration of honeycomb activated carbon, achieving the goal of energy conservation. The entire equipment includes pre filters, adsorption beds, catalytic combustion beds, and fans.   Compared with other organic waste gas treatment methods, this method is a comprehensive treatment mode that draws on the advantages of other modes. The technology is more mature and reliable, and it has significant advantages in treating high air volume and low concentration organic waste gas.   Process design for 2 treatments   2.1 Preprocessing   For organic waste gas, people should first carry out water spraying to remove impurities and soluble organic matter inside the waste gas. After spraying, the gas contains a large amount of moisture and a small amount of dust inside. To avoid the influence of moisture and dust on the effective operation of the activated carbon adsorption bed, people need to use high-efficiency filters for filtration during treatment.   2.2 Adsorption operation   The pre treated organic waste gas is introduced into the adsorption bed under the action of a fan and evenly distributed on the surface of activated carbon. According to the van der Waals forces between molecules, activated carbon will adsorb organic waste gas on the surface. This process takes less time, but the longer the time, the more thorough the adsorption. There is no significant chemical reaction between the two, while the organic waste gas achieves a high purification effect. After purification, the clean exhaust gas can meet the emission standards of relevant atmospheric pollutants. With the action of the fan, it can meet the emission standards of a 15m high exhaust pipe. Each exhaust gas purification treatment system contains adsorption beds at different levels, with two sets for adsorption and one set for desorption. The three sets of equipment can be operated alternately.   2.3 Desorption and Catalytic Combustion   The specific reaction equation is: After the activated carbon adsorption reaches saturation, switch to the desorption bed, which requires additional heat. The heating device is installed inside the catalytic oxidation bed, and the catalyst is preheated simultaneously when turned on. After the catalytic oxidation bed reaches the set temperature, hot air is introduced into the desorption bed, and the organic waste gas is completely desorbed from the surface of the activated carbon under the heating effect.   High concentration organic waste gas enters the oxidation bed under external force, and is burned and decomposed into H2O and CO2 through the catalytic action of platinum metal. The waste gas is purified through this operation. The characteristics of this combustion process are low temperature, fast and flameless, and generate a large amount of heat. People can reuse activated carbon in the desorption and combustion oxidation of organic waste gas, thereby reducing energy consumption.   When the concentration of organic waste gas is high, excessive heat generated by combustion can lead to a higher temperature in the catalytic oxidation bed, which in turn affects the safety of the entire waste gas treatment system. Therefore, the system designed in this article includes a cold air supplement device, which can introduce fresh air to reduce the reaction temperature and ensure the safety of system operation.   2.4 Sewage treatment   After water spray pretreatment, wastewater containing impurities and organic matter is introduced into the sewage treatment tank of the paint spraying workshop for sedimentation, removing large particles of impurities. Wastewater containing organic matter exhibits weak acidity. To reduce the corrosion of equipment caused by wastewater reuse, a small amount of caustic soda needs to be added to carry out neutralization reactions and adjust its acidity and alkalinity. After thorough purification, the wastewater can be recycled and reused in the water spray pretreatment module, and there is basically no discharge of sewage from the sewage treatment unit. The products of sewage centrifugal analysis and the paint residue sediment generated by sedimentation are considered hazardous waste. According to the relevant national requirements for hazardous waste management, qualified hazardous waste disposal units should be commissioned to carry out safe disposal operations.   This plan has numerous advantages. Firstly, a new and efficient activated carbon is used with a stable and reasonable adsorption bed structure, greatly improving the adsorption effect. Secondly, catalytic combustion is carried out using platinum metal to decompose organic waste gas into non-toxic and harmless H2O and CO2, achieving efficient and thorough purification; Again, the combustion process has a lower temperature and is safe. The heat generated during the combustion process can be recycled, resulting in less heat loss and a significant reduction in energy consumption; Finally, the design and installation of system equipment adopt various measures to eliminate safety hazards, with simple operation and ease of later use and management.   3. Operation methods for each component module   3.1 Paint mist filter   Spray painting exhaust gas mainly appears on the spray painting workbench where the workpiece is applied. Many of the high-pressure air sprayed paint stays on the workpiece, while others are discharged with the exhaust gas and become paint mist. These paint sprays have low dust content and small particles, with the majority having a diameter of less than 10mm. If left untreated, it will quickly clog the micropores of activated carbon, causing it to lose its original function. Therefore, paint exhaust gas must first undergo coarse filtration treatment.   3.2 Selection and parameter setting of adsorbent   Activated carbon has the advantages of large surface area, strong adsorption capacity, and low cost. It is currently a common adsorbent for VOCs pollution. It is inconvenient to replace activated carbon in powder form. Activated carbon fibers contain regular micro crystalline structures, which have a large adsorption capacity and are prone to detachment, resulting in high costs. Honeycomb shaped activated carbon has high wind speed and low resistance, and can be applied to the adsorption of low concentration exhaust gases with high air volume. This article selects honeycomb shaped activated carbon, and the structure of the adsorption bed adopts a drawer style assembly mode, which is convenient for filling and disassembling during use.   3.3 Catalytic combustion design   3.3.1 Heat exchanger   The structure of the heat exchanger is relatively complex. In order to reduce production costs and facilitate subsequent installation, this article adopts a relatively simple fixed tube plate heat exchanger, with cold gas flowing through the shell and hot gas flowing through the tube side.   3.3.2 Electric heating chamber   In this scheme, the heating chamber only provides the heat required for preheating the gas during startup. After catalytic combustion of benzene, a large amount of preheating can be utilized, so the required thermal power is relatively low. It can be heated by electricity without the need for additional heating of natural gas or liquefied petroleum gas.   3.3.3 Treatment of insulation module   The temperature inside the catalytic combustion integrated equipment is much higher than room temperature, and insulation treatment needs to be added to avoid harm to the workers. The insulation cotton used for insulation is made of aluminum silicate fiber felt, designed based on the possible high temperature of 400oC in the combustion chamber. The thickness of the insulation cotton is 64mm.   3.4 Design of flame arrester   A flame arrester is composed of many small channels or gaps, and when the flame enters these small channels, many small flame streams are formed. Due to the large heat transfer area of channels or pores, the temperature of the flame decreases after heat exchange through the channel walls, and the flame extinguishes when it reaches a certain degree. Flame arresters are devices used to prevent the spread of flames caused by the evaporation of burning gases or flammable liquids. In VOCs catalytic combustion reactors, the presence of sparks can trigger gas flames and promote the combustion of the entire pipeline network. Therefore, the role of flame arresters is significant. The size of the shell of the flame arrester is directly related to the fluid resistance, and the diameter of the shell is usually about 4 times the diameter of the pipeline used in conjunction, that is, D=4d. This article is designed according to specifications, using open and closed ends of an open flame for ignition. This scheme adopts a flameless combustion method. If D=4d is used, the flame arrester will be too large. Based on actual operational requirements, the data value designed in this article is D=2d and the angle is 60o. The flame arrester is made of 1mm stainless steel, with a pipe diameter of 500mm × 200mm and a diffusion angle of 60o. The height of the front half of the shell is taken as 250 × sin60o=433mm.   4 Conclusion   This scheme adopts the adsorption catalytic combustion method to treat spray paint exhaust gas. Firstly, a filter is used to remove paint mist. Then, through system control, a honeycomb shaped activated carbon adsorption bed is used to continuously adsorb it, and at the same time, saturated activated carbon is desorbed. By using 80% hot air blowing, high air volume and low concentration organic waste gas is concentrated into low air volume and high concentration organic waste gas. At the same time, the catalytic combustion chamber is used to convert the organic gas into CO2 and H2O, while maintaining stable self combustion. Practice has proved that this treatment mode has the advantages of high purification efficiency, no secondary pollution and low operation cost compared with the traditional process.

The appearance of dust particles during the coating process plays an important role in the coating quality of the product.     Reason for formation:   1) During spraying, dust falls onto the surface of the paint film from the spray booth, spraying tools, and air.   2) Dust accumulates on the surface during polishing.   3) The oil cylinder coating has deteriorated or been contaminated.   4) There is dust on the staff's clothes.   5) Plastic parts have static electricity and absorb dust.   6) Moving (walking) around the workpiece causes dust to rise.   7) The air pressure inside the grill is too low.   8) The filter cotton is clogged.   9) There is dust on the floor of the grill.   10) The walls of the grill are very dirty.   11) The ceiling cotton is not suitable.   12) The air ducts are very dirty.   13) There are fibers falling off the torn part of the masking paper.     Resolvent   1) Thoroughly clean the area around the spraying zone.   2) After polishing the paint film and putty, the dust must be blown off.   3) Before spraying, carefully wipe the surface to be coated with a dust cloth and store the dust cloth in a clean polyethylene (plastic bag).   4) Filter the coating with a copper mesh of 140-180 mesh.   5) Wear clean, fiber free, anti-static spray coating work clothes (nylon).   6) Treat with anti-static agent. Do not degrease plastic parts again thereafter.   7) Do not walk around freely in the grill.   8) Regularly check the pressure in the baking room.   9) Regularly replace the filter cotton.   10) Keep the baking room floor clean. Do not place any unnecessary items inside the grill.   11) Regularly clean the grill.   12) Use suitable ceiling cotton.   13) Use an old cloth to clean the 2m long air pipe under the spray gun. When spraying, do not let this pipe fall on the floor. After spraying, hang the air pipe.   14) Use high-quality masking paper to fold the torn edge inward and ensure that the smooth surface of the paper faces outward.   15) When spraying, the needle tip can be used to remove the dust mixed in the paint film. Small dust inside the dry coating can be removed by polishing treatment. If dust settles in the deep layer of the coating, the surface should be polished and re sprayed.

On the morning of February 25, 2021, Min Yun, deputy mayor of Huzhou People's Government and chairman of Huzhou Municipal Committee of the Democratic Revolution, came to Deqing to carry out "three services" activities, visited Zhejiang Huer Painting Environmental Protection Equipment Co., LTD., a company of party members of the Democratic Revolution, and visited Shen Qi, a temporary cadre of the Central Committee of the Democratic Revolution in Germany, in the high-tech zone Management Committee.County Party Committee Standing Committee, Minister of United Front Work Department Xiong excellence, High-tech Zone Party Working Committee member, deputy director of the management committee Shen Qi, county CPPCC Social Law Committee director, Democratic Revolution Deqing grassroots Committee of the party Committee Shen Jianzhong, deputy minister of the United Front work Department of the county Party Committee Fan Yumin accompanied.   Min Yun visited the enterprise exhibition hall of Zhejiang Huier Painting Environmental Protection Equipment Co., LTD., and had a discussion and exchange, listened to the resumption of work and operation of the enterprise during the visit, and gave policy analysis and directional guidance on some problems encountered by the enterprise.   In the discussion, Min Yun pointed out: One is to start the sprint. It is hoped that the party members of the Democratic Revolution entrepreneurs will make new achievements in the New Year, take the initiative to benchmark, seize opportunities, and thrive.Second, we need to innovate and overcome difficulties. In the new development pattern of double cycles at home and abroad, we keep innovating, devote ourselves to research, and strive to make breakthroughs in key links such as enterprise core technology and independent research and development, and take the lead in making scientific and technological innovation.Third, we must serve the overall situation. Under the leadership of the Deqing County Party Committee and the county government, under the guidance of the United Front Work Department of the County Party Committee, we should go all out to prepare for the fourth Moganshan Conference of the Central Committee of the Democratic Revolution.Accelerate the implementation of the signed projects, determine the theme of the new session as soon as possible, and present a gift for the 100th anniversary of the founding of the Communist Party of China.  

Abstract: Shrinkage hole is one of the common defects in painting shop, because it is difficult to repair online, often cause rework. There are many causes of shrinkage holes, this paper mainly introduces the types, causes and solutions of several shrinkage holes in actual production, and provides some references for the analysis and solution of similar problems in other sites. introduction In the painting process, the shrinkage hole defect is difficult to avoid and the repair work is large.There are many reasons for shrinkage, such as defects of the electrophoretic layer, pollution of the electrophoretic layer, pollution of the environment before spraying, pollution of the spraying equipment, pollution after spraying, paint problems, etc.The occurrence of shrinkage holes not only increases the rework cost, but also takes time and effort and is not easy to solve. Therefore, it is a very meaningful research direction to improve the level of coating process and reduce production cost to analyze the causes of shrinkage holes in automobile painting process, find corresponding solutions and eliminate shrinkage holes as much as possible. Causes of shrinkage holes   1.1 Introduction to coating process After the BIW enters the painting workshop for pre-treatment electrophoresis, the sealant process is carried out, and then the BIW arrives at the electrophoresis grinding station, where some paint slag, residual glue, welding slag and other defects affecting the next top paint process are disposed of, and then the biW enters the spray booth for spraying. The spray painting process uses the IP2 process, also known as the no-medium paint process, in which the color paint coating is BC1 primer layer and BC2 color paint layer, BC2 spray into the flash dry oven, then spray varnish, and finally into the top paint oven.   1.2 Form of shrinkage hole Defect description: The crater on the surface of the paint film (see Figure 1), which can be large or small in diameter, usually between 0.2-1.0mm visible to the naked eye. Foreign bodies can be observed in some depressions, but not in others. Some shrinkage holes can be observed in the wet film state. The difference between the shrinkage hole and the pinhole: 1) the shrinkage hole is generally larger than the pinhole, the boundary is clear, and the depth is shallower than the pinhole; 2) Pinhole holes are small. Like a hole pierced with a needle, the center looks black when observed because of its small and deep; 3) Pinholes are generally caused by the ejection of air bubbles or solvent bubbles formed by the paint layer.   1.3 Causes of shrinkage holes The main reason for shrinkage holes is that foreign pollutants (dripping, splashing, purging, volatilization, etc.) cause changes in the surface tension of the substrate or coating, resulting in uneven film formation. It is generally divided into the following aspects: 1) there is pollution in the paint; 2) There is environmental pollution in the process; 3) personnel introduce pollution; 4) Cleaning supplies pollution; 5) Replacement of relevant materials (such as compressed air, chamber glass glue); 6) Introduction of non-standard materials; 7) No certified oil or grease is used.   1.4 Several conventional material shrinkage evaluation test methods The test methods generally include: rubbing the sample with the test plate or coating it on the test plate, spraying it and observing the wet film state; Dry film test; Sample and paint mixing test; There are also differences in factory methods such as contamination testing after mixing samples with solvents. The general test process is to simulate the situation and conditions of the sample to be tested in actual use.   2.Problem Solved 1) For the indoor and outdoor spray painting departments, the top paint engineer takes the lead and involves several departments including production, maintenance, cleaning and planning to jointly develop the inspection list and conduct detailed investigation from five aspects: human, machine, material, method and environment; 2) It was found that there was reconstruction construction under the conveyor chain from electrophoresis grinding to painting booth by the planning department, which was carried out only during the day and stopped after 17:00, which basically coincided with the occurrence of shrinkage hole defects. Moreover, after finishing, cleaning and standardized operation of the construction site, the proportion of shrinkage holes decreased significantly, and the same problem was solved.   03 Conclusion Shrinkage problems are common in actual production, and they are always in the cycle of problem occurrence, investigation and solution. The special feature of shrinkage hole problem is that we can not always find the real root cause and eliminate the defects from the source, but the solution of the problem cannot be stopped. Only by constantly summarizing experience, summarizing methods, looking for rules, and sorting out the problem solving process can we not be busy when encountering problems and accurately find the starting point. The more common cause of shrinkage problems is pollution, whether it is the electrophoretic layer, the conveying environment, the spraying material, the spraying environment, the spraying equipment will have pollution (especially silicone) problems, in these links need to make great efforts to manage. 1) Materials and accessories: including the use of Vaseline, lubricants, robot overalls, pipes, sealing materials replacement, use, brand change, etc., should be recorded and documented. Paint material is also a very key one, factory shrinkage test is to ensure the shrinkage of the material problem is the first checkpoint, materials into the factory after the system, daily spot inspection and observation of equipment operation, circulation system temperature, pressure is also essential; 2) Personnel management: the wearing of gloves at key stations, the use of skin care products, and the standardization of personnel operations. The maintenance of equipment, whether it is spraying robots or conveying equipment, should be carried out in accordance with the requirements of regular maintenance, cleaning, inspection and other work; 3) Environment: The cleanliness of the environment is the first important event for painting, which is not only very important for avoiding shrinkage defects, but also the most important for common coating defects such as particles and fibers. In short, the management of shrinkage hole defects is a system management problem, involving all aspects, and a lot of work needs to be done before the problem occurs. After the problem occurs, we should be patient to sort out, look for changes, and improve and solve the problem.