Centrifugal dehydrator maintenance points and common faults analysis to ensure efficient operation

In today's industrial production and sewage treatment and many other fields, the centrifugal dehydrator is undoubtedly one of the key core equipment. Its stable and efficient operation is directly related to the production efficiency and product quality. From a professional perspective, this article deeply and meticulously analyzes the key points of centrifugal dehydrator maintenance, and elaborates on the causes of common faults and effective means of elimination, striving to provide a comprehensive and practical technical guide for equipment operators and maintenance personnel fighting on the front line, and to ensure that the equipment can always maintain efficient and reliable operation. The centrifugal dehydrator cleverly uses the physical principle of centrifugal force to forcefully throw out the water in the material at a very fast speed, thereby perfectly achieving solid-liquid separation. Whether it is the ore selection process in mining, the complex material handling link in the chemical industry, or the fine processing steps of raw materials in the food processing field, as well as the key stage of municipal sewage treatment, it plays an irreplaceable and important role. However, given that its working environment is often complex and harsh, there are many internal operating parts and it is always in a high-speed rotation state, which puts extremely high demands on its maintenance work. Once the equipment fails suddenly, it will not only bring the normal production process to a halt, but also very likely cause a series of safety hazards, with disastrous consequences. 2. Maintenance points of centrifugal dehydrators (I) Maintenance of mechanical parts 1. As key components directly involved in the core task of material separation, the wear condition of the drum and spiral must be paid special attention. During the continuous operation of the equipment, the material is continuously washed and rubbed, which will gradually erode their surfaces. Therefore, it is necessary to arrange shutdown operations according to the established cycle, use professional precision measuring tools to carefully measure the wall thickness changes, and observe the appearance in all directions for abnormal signs such as minor scratches and deformation. Once it is found that the degree of wear exceeds the prescribed safety limit, it must be replaced in time, otherwise it will have a negative impact on the separation effect, and will break the dynamic balance of the equipment, causing a series of chain problems. Before each startup, it is crucial to accurately ensure that the gap between the drum and the spiral is in line with the technical specifications of the equipment. If the gap is too small, it is very easy to induce interference between components, and even serious jamming; while if the gap is too large, it will inevitably reduce the dehydration efficiency and fail to achieve the expected production goals. Generally speaking, it is most convenient and reliable to measure the gap with the help of a professional tool such as a feeler gauge. After the measurement is completed, fine adjustments should be made strictly in accordance with the equipment operation manual. 2. Bearings Bearings are the core hub components that support the high-speed rotation of the drum and are subjected to huge radial and axial forces. In daily inspection work, it is important to always pay attention to the temperature fluctuations and vibration of the bearings. At this time, with the help of advanced professional tools such as infrared thermometers and vibration sensors, key data can be accurately obtained. Under normal operating conditions, the bearing temperature should be stably maintained within the specified range (generally speaking, not exceeding 70-80℃). If the temperature rises abnormally, it is very likely that there is a problem in the lubrication link, the equipment is overloaded, or the bearing itself has been damaged. Strictly follow the cycle carefully recommended by the equipment manufacturer and replace the bearing grease regularly. When choosing grease, be sure to select high-quality products that are suitable for the working conditions of the equipment to ensure that the bearings can be fully and long-term lubricated, thereby effectively extending their service life. It is worth noting that in the process of replacing grease, the bearing seat must be thoroughly cleaned, the old grease residue and various impurities must be thoroughly removed, and it must be resolutely prevented from contaminating the new grease and affecting the lubrication effect. (II) Electrical system maintenance 1. Motor As the power source of the centrifugal dehydrator, ensuring its smooth and normal operation is undoubtedly the foundation for the stable operation of the equipment. Regularly use a megohmmeter to accurately measure the insulation resistance of the motor. The measured value must strictly comply with the requirements of the electrical specifications. This step can effectively prevent short-circuit faults caused by adverse factors such as insulation aging and moisture, and ensure the safe operation of the motor. Always pay close attention to the heat dissipation of the motor, clean up the dust and debris accumulated on the surface of the motor in time, and make every effort to ensure that the heat dissipation duct is always unobstructed. It should be noted that the motor will continue to generate a lot of heat during operation. Once the heat dissipation link is blocked and the heat cannot be dissipated in time, the temperature will rise sharply, causing irreversible damage to the winding insulation, which will not only reduce the working efficiency of the motor, but in severe cases, it will even directly cause the motor to burn out, causing significant losses. 2. Control cabinet The control cabinet integrates various key electrical components such as contactors, relays, and inverters. They work together to control the operation rhythm of the equipment. Regularly carry out comprehensive dust removal operations on the control cabinet to prevent dust accumulation, prevent electrical short circuit failures caused by dust, and ensure that the internal electrical environment is stable and reliable. At the same time, carefully check whether there is any looseness in each terminal, and make sure that the electrical connection is tight and reliable to avoid the problem of virtual connection, because virtual connection will cause current instability, which will cause abnormal fluctuations in equipment operation. For components such as frequency converters that play a key role in regulating the operation of equipment, according to their exclusive user manuals, regularly conduct rigorous verification of parameter settings to confirm whether they are correct, and pay close attention to whether there are any abnormal alarm messages pop up. It is necessary to know that the frequency converter parameters are directly related to the precise control of the motor speed and torque output. Once the parameters are set incorrectly, the centrifugal dehydrator will not be able to achieve the expected operating state. What's more, it may cause serious damage to the equipment and affect the production progress. (III) Daily cleaning and maintenance 1. Body cleaning After each use of the equipment, the material residues and water stains adhering to the surface of the centrifugal dehydrator body must be cleaned promptly and thoroughly. If the material residue accumulates for a long time, it will gradually corrode the shell of the machine body and reduce the overall structural strength of the equipment; and once the water stains penetrate into the internal electrical components, it is very likely to cause a short circuit fault and endanger the safety of the equipment. When cleaning the machine body, it is recommended to use a damp cloth to gently wipe the shell. For those stubborn dirt that is difficult to remove, you can use a mild and non-corrosive detergent to carefully handle it, but be sure to avoid the detergent flowing into the sensitive and delicate areas inside the equipment to prevent damage to the internal components. 2. According to the established cycle, the feed and discharge pipelines should be strictly checked regularly for the patency of the feed and discharge pipelines, and the scale and various blockages that may be formed inside the pipelines should be cleaned in time. Poor feeding will cause uneven distribution of materials when entering the drum, which will seriously affect the dehydration effect; and the blockage of the discharge will make it impossible for the separated materials to be discharged smoothly in time, causing a sharp increase in the internal pressure of the equipment, which will not only damage the seals and cause leakage risks, but also impact the operating stability of the entire equipment. In the face of pipeline blockage problems, professional tools such as flushing and unblocking can be flexibly used for efficient cleaning and maintenance. 3. Common troubleshooting of centrifugal dehydrators (I) Abnormal vibration 1. Cause analysis Drum imbalance: The material is not evenly distributed in the drum, or the drum itself is worn due to long-term use, and the dynamic balance is not accurately calibrated after repair. These factors may cause the center of gravity of the drum to shift. When the drum rotates at high speed, it will produce violent and extremely destructive vibrations. Bearing damage: As detailed in the previous article, once the bearing fails, the support stability of the drum will be completely lost, which will cause strong vibrations. In addition to common wear and fatigue damage, if the installation process is improperly operated, resulting in the inner ring of the bearing and the shaft, the outer ring and the bearing seat are too loose or too tight, it will also cause the vibration amplitude to increase sharply, posing a great threat to the operation of the equipment. Loose components: After a long period of continuous operation, the bolts and nuts connecting the drum, spiral, motor and other key components are prone to looseness, which will directly destroy the integrity of the equipment, allowing the vibration to be transmitted and amplified between the components, seriously affecting the normal operation of the equipment. Resonance: When the speed of the centrifugal dehydrator is unexpectedly close to or exactly equal to its natural frequency, resonance will occur, and the vibration amplitude will increase exponentially. The reason for this phenomenon may be the result of many factors such as the insufficient stability of the equipment foundation, the loosening of the anchor bolts, or the strong vibration source interference in the surrounding area. 2. Elimination method For the problem of unbalanced drum, first of all, the machine must be stopped decisively and the materials in the drum must be thoroughly cleaned. If the vibration problem still persists, the drum must be professionally dynamic balanced. If necessary, the worn parts must be re-processed and repaired to ensure that the drum is restored to the optimal balance state. If there is a problem with the bearing, the machine should be stopped immediately, the damaged bearing should be replaced quickly, and the accurate assembly should be carried out in strict accordance with the installation process standard requirements. It is imperative to ensure that the matching accuracy between the components reaches the ideal state and ensure that the bearing can stably support the rotation of the drum. Carry out a comprehensive tightening inspection of all connecting parts of the equipment, tighten the loose bolts one by one in strict accordance with the specified torque, and conduct regular re-inspections in subsequent daily inspections to form a long-term supervision mechanism to prevent the loosening problem from occurring again. In order to effectively avoid the risk of resonance, on the one hand, the basic design of the equipment should be optimized and upgraded, and the foundation structure should be reinforced to ensure that the anchor bolts are tightened without loosening, so as to improve the stability of the equipment from the root; on the other hand, the variable frequency speed regulation technology can be fully utilized to flexibly adjust the equipment running speed, cleverly avoid the resonance range, and ensure the smooth operation of the equipment. (II) Poor dehydration effect 1. Cause analysis The feed concentration is too low or too high: When the feed concentration is too low, it is difficult for the material to condense in the drum to form an effective precipitation layer, which makes it very easy for the liquid to be thrown out with the solid phase, and finally leads to a significant reduction in the dehydration rate; on the contrary, if the feed concentration is too high, the fluidity of the material will become extremely poor, and it is easy to accumulate and clog in the drum, which seriously hinders the dehydration process and cannot achieve the expected separation effect. Abnormal gap between the drum and the spiral: The problem of too large a gap has been mentioned in the previous article. This will greatly shorten the dehydration time, making it too late for the water to be fully thrown out, affecting the dehydration quality; if the gap is too small, it will cause the material to pass through and even cause the drum to be blocked, which will also have a negative impact on the dehydration effect and reduce production efficiency. Insufficient speed: As we know, centrifugal force is proportional to the square of the speed. Once the speed is not enough, the centrifugal force generated will be difficult to meet the requirements of completely separating water. There are many reasons for insufficient speed, which may be sudden failure of the motor, incorrect setting of inverter parameters, or slippage of the belt when using belt drive, etc. These factors will hinder the normal dehydration operation of the equipment. Filter blockage: The filter is responsible for intercepting solid materials during the operation of the equipment. However, as the use time increases, fine particles will gradually block the pores of the filter, making the water seepage blocked, which will lead to a continuous decrease in dehydration efficiency and cannot meet production needs. 2. Elimination method According to the unique characteristics of the material itself and the specific requirements of the equipment, strictly control the feed concentration to stabilize it in a reasonable range. If necessary, an adjustment device such as a stirrer, concentration equipment, etc. can be cleverly added to the front end of the feed to ensure that the feed concentration is appropriate through pretreatment means, laying a good foundation for subsequent dehydration operations. Once the dehydration effect is found to be abnormal, the machine should be stopped immediately, and the gap between the drum and the spiral should be accurately measured and adjusted to ensure that it returns to a reasonable range; at the same time, in the daily operation process, the monitoring of the gap should be strengthened to timely discover and deal with the gap change problem in time to ensure the continuous and efficient operation of the equipment. For the problem of insufficient speed, quickly check the motor and transmission system faults. If the motor winding is damaged, repair it in time; carefully check the inverter parameters and perform accurate calibration; if belt drive is used, carefully adjust the belt tension. If the belt is severely worn, decisively replace the new belt, and restore the normal speed of the equipment through a series of measures to ensure that the centrifugal force meets the standard and achieve efficient dehydration. Regularly clean the filter screen, and flexibly select scientific and effective methods such as chemical cleaning and high-pressure water washing according to the actual situation to ensure that the filter screen pores are always unobstructed; at the same time, pay close attention to the wear of the filter screen, and replace the new filter screen in time according to the degree of wear to ensure the stable and reliable filtering performance of the equipment. (III) Abnormal noise 1. Cause analysis Mechanical friction: If the lubrication condition between the drum and the spiral, bearings, seals and other parts is poor or the matching accuracy is deviated, it is easy to cause strong mechanical friction, which will produce sharp, harsh and disturbing noise. For example, the seals will age and deform due to long-term use, and excessive friction will occur between the rotating shaft; if the bearing is short of oil, dry friction will occur between the rolling element and the inner and outer rings. These frictions will cause a sudden increase in noise and affect the operating environment of the equipment. Material impact: When the feed speed is too fast, the material particles are too large, or the material particles are extremely unevenly distributed, the material will have a greater impact force on the internal components at the moment of entering the drum, and this impact force will be released in the form of noise. Especially when processing materials containing hard particles, since the impact force of hard particles is stronger, the impact noise generated is more obvious, posing a threat to the stability of equipment operation. Component damage: If key components such as drums and spiral blades have structural damage such as cracks and fractures, they will make abnormal noises during high-speed rotation due to the destruction of structural integrity. In addition, if the motor fan blades are damaged or unbalanced, the noise will increase when the fan is running, interfering with the normal operation of the equipment. 2. Elimination method Strengthen lubrication management, strictly check each lubrication point regularly according to the established cycle, and replenish grease or lubricating oil in time once it is found that the grease or lubricating oil is insufficient to ensure that all components are well lubricated; at the same time, seals, bearings and other parts that have been worn and deformed should be replaced decisively and promptly, and mechanical friction can be effectively reduced by optimizing the matching accuracy of parts to eliminate noise sources. According to the characteristics of the material, the feed speed should be adjusted reasonably to avoid feeding too fast. And according to actual needs, install an appropriate feed grid or crusher to pre-treat the feed, control the particle size of the material within a reasonable range, reduce the impact force of the material, and reduce the possibility of impact noise. Once abnormal noise is detected in the equipment, the machine should be shut down immediately, and the internal parts of the equipment should be fully inspected by using flaw detectors, visual inspections and other means to accurately find the damaged parts, and then quickly repair or replace the damaged parts; for the motor fan problem, it should be dynamically balanced in time. If the blades are seriously damaged, replace them with new blades directly to ensure that the fan runs smoothly and the noise returns to normal levels. 4. Conclusion In order to achieve efficient and stable operation of the centrifugal dehydrator, scientific, reasonable, rigorous and meticulous maintenance work is indispensable, as well as the ability to quickly and accurately eliminate the faults when they occur. By meticulously implementing the maintenance points of mechanical parts and electrical systems, and persistently strengthening daily cleaning and maintenance work, equipment operators and maintenance personnel can effectively prevent faults from occurring, greatly extend the service life of the equipment, and reduce the cost of equipment operation and maintenance. When the failure unfortunately occurs, with a deep insight and understanding of the common causes of the failure, quickly taking highly targeted elimination measures can minimize the equipment downtime and ensure that production activities can proceed in an orderly and smooth manner. Looking into the future, with the rapid development of science and technology, centrifugal dehydrators will surely move towards a new direction of intelligence and efficiency. The corresponding maintenance and fault diagnosis technologies also need to keep pace with the times and be continuously updated and upgraded to meet the growing production needs of the new era and help various industries to flourish.