Q: Working principle of cooling tower
A: Cooling tower is a kind of equipment that uses the contact between water and air to dissipate the waste heat generated in industry or refrigeration and air conditioning through evaporation. The basic principle of its work is: the dry (low enthalpy) air enters the cooling tower from the air inlet network after being pumped by the fan; High temperature water molecules with high partial pressure of saturated steam flow to air with low pressure, and damp heat (high enthalpy) water is sprayed into the tower by the self seeding water system.
When water droplets come into contact with air, on the one hand, due to the direct heat transfer between air and, on the other hand, due to the pressure difference between the water vapor surface and air, evaporation occurs under the action of pressure. At present, it is to take away the latent heat of evaporation and take away the heat in the water, that is, evaporation heat transfer, so as to achieve the purpose of cooling.
When water droplets come into contact with air, on the one hand, due to the direct heat transfer between air and, on the other hand, due to the pressure difference between the water vapor surface and air, evaporation occurs under the action of pressure. At present, it is to take away the latent heat of evaporation and take away the heat in the water, that is, evaporation heat transfer, so as to achieve the purpose of cooling.
Q: Working process of cooling tower
A: Take the working process of circular countercurrent cooling tower as an example: the hot water main machine room will circulate the water pressure to the water sowing system of the cooling tower through the pipe, transverse throat, curved throat and central throat through the water pump at a certain pressure, and evenly sprinkle the water on the filler through the small hole on the water sowing pipe; The dry low Han value air enters the tower from the bottom air inlet network under the action of the fan. When the hot water flows through the filler surface, a water film is formed to exchange heat with the air. The hot air with high humidity and high Han value is extracted from the top, and the cooling water drops into the bottom basin and flows into the main engine through the outlet pipe.
Generally, the air entering the tower is the air with dry and low wet bulb temperature. There is an obvious concentration difference and kinetic energy pressure difference between water and air. When the fan is running, under the action of static pressure in the tower, water molecules continue to evaporate into the air and become water vapor molecules, and the average kinetic energy of the remaining water molecules will be reduced, Thus, the temperature of circulating water decreases.
From the above analysis, it can be seen that the evaporation cooling has nothing to do with the air temperature (commonly known as the dry bulb temperature) being lower or higher than the water temperature. As long as the water molecules can continuously evaporate into the air, the water temperature will decrease. However, the evaporation of water into the air will not continue endlessly. When the air in contact with water is unsaturated, the water molecules evaporate into the air continuously, but when the air on the water air contact surface reaches saturation, the water molecules cannot evaporate, but are in a state of dynamic equilibrium. The number of water molecules evaporated is equal to the number of water molecules returned from the air to the water, and the water temperature remains unchanged. It can be seen that the drier the air in contact with water, the easier evaporation will be and the easier the water temperature will be reduced.
Generally, the air entering the tower is the air with dry and low wet bulb temperature. There is an obvious concentration difference and kinetic energy pressure difference between water and air. When the fan is running, under the action of static pressure in the tower, water molecules continue to evaporate into the air and become water vapor molecules, and the average kinetic energy of the remaining water molecules will be reduced, Thus, the temperature of circulating water decreases.
From the above analysis, it can be seen that the evaporation cooling has nothing to do with the air temperature (commonly known as the dry bulb temperature) being lower or higher than the water temperature. As long as the water molecules can continuously evaporate into the air, the water temperature will decrease. However, the evaporation of water into the air will not continue endlessly. When the air in contact with water is unsaturated, the water molecules evaporate into the air continuously, but when the air on the water air contact surface reaches saturation, the water molecules cannot evaporate, but are in a state of dynamic equilibrium. The number of water molecules evaporated is equal to the number of water molecules returned from the air to the water, and the water temperature remains unchanged. It can be seen that the drier the air in contact with water, the easier evaporation will be and the easier the water temperature will be reduced.
Q: Application scope of cooling tower
A: The waste heat generated in the process of industrial production or refrigeration process is generally guided by cooling water. The function of the cooling tower is to heat exchange the cooling water with waste heat with the air in the tower, so that the waste heat is transmitted to the air and dispersed into the atmosphere. For example, in the thermal power plant, the boiler heats the water into high-temperature and high-pressure steam, pushes the steam turbine to do work, and makes the generator generate electricity. The waste steam after the steam turbine does work is discharged into the condenser for heat exchange with the cooling water, condensed into water, and then pumped back to the boiler for recycling. In this process, the waste heat of exhaust steam is transferred to the cooling water to raise the water temperature. The cooling water with waste heat transfers the heat to the air in the cooling tower and is discharged into the atmospheric environment from the air duct. Application scope of cooling tower: it is mainly used in air conditioning cooling system, refrigeration series, injection molding, tanning, foaming, power generation, steam turbine, aluminum profile processing, air compressor, industrial water cooling and other fields. The most widely used are air conditioning cooling, refrigeration and plastic chemical industries.
Q: Cooling Tower Operation and Maintenance
A: The normal operation of the cooling tower in terms of thermal performance mainly includes three factors: the tower's circulating water volume, air volume and heat conduction characteristics. When any one or more of these conditions change, the tower's operation will be affected.
In order to ensure the good performance of the cooling tower, the tower should be kept clean and the water distribution and air volume distribution should be uniform so as to obtain continuous and ideal cooling capacity. Do not allow dirt, algae, moss, etc. to accumulate to avoid clogging the water distribution system or the drainage (outlet) system. The measuring orifice plate should also be kept free of debris to ensure correct metering and control.
The following aspects cause changes in air flow: changing the static pressure point of the fan working point, changing the fan speed or changing the inclination angle of the fan blade. In addition, the accumulation of scale, grease, algae on the filler or water collector, and excessive water load flowing into the filler will also cause a reduction in air flow. The fan installed in the wind tube, if damaged, will increase the gap from the top of the blade to the inner wall of the wind tube and reduce the efficiency of the fan. After the shell plate of the tower falls, air leakage will also reduce the amount of air flowing through the filler. Deformation and shedding of fillers, nozzle blockage, and deposition of impurities in the water distribution pipes are all important factors that cause poor heat transfer effects.
If these problems are not properly maintained in time, they will cause serious damage to air flow, water flow, and heat conduction. However, the maintenance and management of cooling towers are often not taken seriously and are neglected by people. This problem was once common. The main reason was that people did not understand the importance and necessity of cooling tower maintenance and did not pay enough attention to it, which caused abnormal operation or failure of cooling towers.
In order to ensure the good performance of the cooling tower, the tower should be kept clean and the water distribution and air volume distribution should be uniform so as to obtain continuous and ideal cooling capacity. Do not allow dirt, algae, moss, etc. to accumulate to avoid clogging the water distribution system or the drainage (outlet) system. The measuring orifice plate should also be kept free of debris to ensure correct metering and control.
The following aspects cause changes in air flow: changing the static pressure point of the fan working point, changing the fan speed or changing the inclination angle of the fan blade. In addition, the accumulation of scale, grease, algae on the filler or water collector, and excessive water load flowing into the filler will also cause a reduction in air flow. The fan installed in the wind tube, if damaged, will increase the gap from the top of the blade to the inner wall of the wind tube and reduce the efficiency of the fan. After the shell plate of the tower falls, air leakage will also reduce the amount of air flowing through the filler. Deformation and shedding of fillers, nozzle blockage, and deposition of impurities in the water distribution pipes are all important factors that cause poor heat transfer effects.
If these problems are not properly maintained in time, they will cause serious damage to air flow, water flow, and heat conduction. However, the maintenance and management of cooling towers are often not taken seriously and are neglected by people. This problem was once common. The main reason was that people did not understand the importance and necessity of cooling tower maintenance and did not pay enough attention to it, which caused abnormal operation or failure of cooling towers.
Q: Cooling tower components
A: The cooling tower body is generally composed of the upper, middle and lower parts. Its internal structure is composed of a fan (referring to a mechanical ventilation countercurrent cooling tower), a water collector (removal), a water distribution system, a water spray filler, an air inlet window, and a chassis (or a water pool) from top to bottom.
Component introduction:
1. Water spray filler
It is the main component for cooling hot water in the tower, called the "gastrointestinal system". The hot water to be cooled is splashed into water droplets or forms a water film after multiple splashes, which increases the contact area between water and air and prolongs the contact time, promotes heat exchange between hot water and air, and cools the water.
Component introduction:
1. Water spray filler
It is the main component for cooling hot water in the tower, called the "gastrointestinal system". The hot water to be cooled is splashed into water droplets or forms a water film after multiple splashes, which increases the contact area between water and air and prolongs the contact time, promotes heat exchange between hot water and air, and cools the water.
2. Water distribution system
A: The function of the water distribution system is to evenly distribute the hot water on the entire filler. Whether the hot water is evenly distributed has a great impact on the cooling effect. If the water volume is unevenly distributed, it will not only directly reduce the cooling effect of the water, but also cause some cooling water droplets to splash and drift out of the tower, increasing water loss.
3. Ventilation equipment
In the wind tube of the upper tower body of the mechanical ventilation cooling tower, a fan driven by a motor is installed (the blower type is installed in the lower part), and the designed air flow (i.e. air volume) is generated by the rotation of the fan to ensure sufficient air and water for heat exchange and achieve the cooling effect.
4. Air distribution device
The air distribution device refers to the air inlet, shutters and air guide plates, etc., the purpose of which is to guide the air to be evenly distributed over the entire cross-section of the cooling tower, so that the air does not produce unevenness, vortex, reflux, etc. in the tower, and ensure uniform contact between water and air.
5. Ventilation duct
The function of the ventilator is to create good aerodynamic conditions, reduce ventilation resistance, send the hot and humid air discharged from the cooling tower into the sky, and prevent or reduce the reflux of hot and humid air. The ventilator of the mechanical ventilation cooling tower is also called the ventilator, which is basically made of fiberglass at present. The ventilator of the ventilator type natural ventilation cooling tower has a large diameter and is high. It plays the role of ventilation and sending humid air to the sky, and is cast with reinforced concrete.
6. Water collector
The water droplets carried in the wet air to be discharged from the tower are separated from the air by a water collector in the tower to reduce the loss of escaping (drifting) water and the impact on the surrounding environment.
7. Tower body
Refers to the outer shell of the cooling tower. The tower body of the mechanical ventilation cooling tower and the wind tube type natural ventilation cooling tower is closed, and its function is to support, enclose and organize appropriate airflow; the tower body of the open cooling tower is made open along the tower height to allow air to enter the tower naturally.
8. Water collection tank
It is located at the bottom of the cooling tower (for small and medium-sized towers, some have a chassis at the bottom without a water collection tank), collecting cooling water falling from the water-spraying filler of multiple towers. The water collection tank has a certain volume and sometimes plays a role in regulating the amount of water.
9. Inlet and outlet pipes
The water inlet pipe transports hot water to the water distribution system of the cooling tower. A valve is installed on the water inlet pipe to adjust the amount of water entering the tower. The outlet pipe (located under the chassis of small and medium-sized towers) sends cooling water to water-using equipment or a pool. There is a pool under the large tower, and there is no outlet pipe. Generally, it refers to the water pipe that the water pump pumps from the pool to the water-using equipment. There are also supplementary water pipes, sewage pipes, overflow pipes, vent pipes, etc. in the water collection pool.
3. Ventilation equipment
In the wind tube of the upper tower body of the mechanical ventilation cooling tower, a fan driven by a motor is installed (the blower type is installed in the lower part), and the designed air flow (i.e. air volume) is generated by the rotation of the fan to ensure sufficient air and water for heat exchange and achieve the cooling effect.
4. Air distribution device
The air distribution device refers to the air inlet, shutters and air guide plates, etc., the purpose of which is to guide the air to be evenly distributed over the entire cross-section of the cooling tower, so that the air does not produce unevenness, vortex, reflux, etc. in the tower, and ensure uniform contact between water and air.
5. Ventilation duct
The function of the ventilator is to create good aerodynamic conditions, reduce ventilation resistance, send the hot and humid air discharged from the cooling tower into the sky, and prevent or reduce the reflux of hot and humid air. The ventilator of the mechanical ventilation cooling tower is also called the ventilator, which is basically made of fiberglass at present. The ventilator of the ventilator type natural ventilation cooling tower has a large diameter and is high. It plays the role of ventilation and sending humid air to the sky, and is cast with reinforced concrete.
6. Water collector
The water droplets carried in the wet air to be discharged from the tower are separated from the air by a water collector in the tower to reduce the loss of escaping (drifting) water and the impact on the surrounding environment.
7. Tower body
Refers to the outer shell of the cooling tower. The tower body of the mechanical ventilation cooling tower and the wind tube type natural ventilation cooling tower is closed, and its function is to support, enclose and organize appropriate airflow; the tower body of the open cooling tower is made open along the tower height to allow air to enter the tower naturally.
8. Water collection tank
It is located at the bottom of the cooling tower (for small and medium-sized towers, some have a chassis at the bottom without a water collection tank), collecting cooling water falling from the water-spraying filler of multiple towers. The water collection tank has a certain volume and sometimes plays a role in regulating the amount of water.
9. Inlet and outlet pipes
The water inlet pipe transports hot water to the water distribution system of the cooling tower. A valve is installed on the water inlet pipe to adjust the amount of water entering the tower. The outlet pipe (located under the chassis of small and medium-sized towers) sends cooling water to water-using equipment or a pool. There is a pool under the large tower, and there is no outlet pipe. Generally, it refers to the water pipe that the water pump pumps from the pool to the water-using equipment. There are also supplementary water pipes, sewage pipes, overflow pipes, vent pipes, etc. in the water collection pool.
Q: Cooling tower introduction
A: A cooling tower is a device that uses the contact between water and air to dissipate waste heat generated in industry or refrigeration and air conditioning through evaporation. Waste heat generated in industrial production or refrigeration processes is generally directed away with cooling water. A certain amount of water is drawn from natural water bodies such as rivers, lakes, and seas as cooling water. The cooling process equipment absorbs waste heat to increase the water temperature and then discharges it into rivers, lakes, and seas. This cooling method is called direct current cooling. When direct current cooling conditions are not available, a cooling tower is required for cooling. The function of the cooling tower is to exchange heat between the cooling water carrying waste heat and the air in the tower, so that the waste heat is transferred to the air and dissipated into the atmosphere.
1. Basic working principle of cooling tower
After being pumped by the fan, dry (low enthalpy) air enters the cooling tower from the air inlet network; high-temperature water molecules with high saturated steam partial pressure flow to the air with low pressure, and humid (high enthalpy) water is sprinkled into the tower from the water seeding system. When water droplets come into contact with air, on the one hand, due to direct heat transfer between air and water, on the other hand, due to the pressure difference between the water vapor surface and the air, evaporation occurs under the action of pressure, taking away the heat in the water, that is, evaporation heat transfer, thereby achieving the purpose of cooling.
2. Working process of cooling tower
Take the working process of circular countercurrent cooling tower as an example:
Hot water is pumped from the main engine room through the pipe, horizontal throat, curved throat, and center throat at a certain pressure to press the circulating water into the water spreading system of the cooling tower, and the water is evenly spread on the filler through the small holes on the water spreading pipe; dry low-humidity air enters the tower through the bottom air inlet net under the action of the fan, and the hot water forms a water film and exchanges heat with the air when it flows through the surface of the filler. The hot air with high humidity and high humidity is extracted from the top, and the cooling water drips into the bottom basin and flows into the main engine through the outlet pipe.
Generally speaking, the air entering the tower is dry air with a low wet-bulb temperature. There is an obvious concentration difference and kinetic pressure difference of water molecules between water and air. When the fan is running, under the action of the static pressure in the tower, water molecules continue to evaporate into the air and become water vapor molecules. The average kinetic energy of the remaining water molecules will decrease, thereby reducing the temperature of the circulating water.
From the above analysis, it can be seen that evaporative cooling has nothing to do with the air temperature (usually the dry-bulb temperature) being lower or higher than the water temperature. As long as the water molecules can continue to evaporate into the air, the water temperature will decrease. However, the evaporation of water into the air will not continue endlessly.
When the air in contact with water is unsaturated, water molecules continue to evaporate into the air, but when the air on the water-gas contact surface reaches saturation, the water molecules cannot evaporate out, but are in a dynamic equilibrium state. The number of water molecules evaporated is equal to the number of water molecules returned from the air to the water, and the water temperature remains unchanged. From this, it can be seen that the drier the air in contact with water, the easier it is to evaporate and the easier it is to reduce the water temperature.
1. Basic working principle of cooling tower
After being pumped by the fan, dry (low enthalpy) air enters the cooling tower from the air inlet network; high-temperature water molecules with high saturated steam partial pressure flow to the air with low pressure, and humid (high enthalpy) water is sprinkled into the tower from the water seeding system. When water droplets come into contact with air, on the one hand, due to direct heat transfer between air and water, on the other hand, due to the pressure difference between the water vapor surface and the air, evaporation occurs under the action of pressure, taking away the heat in the water, that is, evaporation heat transfer, thereby achieving the purpose of cooling.
2. Working process of cooling tower
Take the working process of circular countercurrent cooling tower as an example:
Hot water is pumped from the main engine room through the pipe, horizontal throat, curved throat, and center throat at a certain pressure to press the circulating water into the water spreading system of the cooling tower, and the water is evenly spread on the filler through the small holes on the water spreading pipe; dry low-humidity air enters the tower through the bottom air inlet net under the action of the fan, and the hot water forms a water film and exchanges heat with the air when it flows through the surface of the filler. The hot air with high humidity and high humidity is extracted from the top, and the cooling water drips into the bottom basin and flows into the main engine through the outlet pipe.
Generally speaking, the air entering the tower is dry air with a low wet-bulb temperature. There is an obvious concentration difference and kinetic pressure difference of water molecules between water and air. When the fan is running, under the action of the static pressure in the tower, water molecules continue to evaporate into the air and become water vapor molecules. The average kinetic energy of the remaining water molecules will decrease, thereby reducing the temperature of the circulating water.
From the above analysis, it can be seen that evaporative cooling has nothing to do with the air temperature (usually the dry-bulb temperature) being lower or higher than the water temperature. As long as the water molecules can continue to evaporate into the air, the water temperature will decrease. However, the evaporation of water into the air will not continue endlessly.
When the air in contact with water is unsaturated, water molecules continue to evaporate into the air, but when the air on the water-gas contact surface reaches saturation, the water molecules cannot evaporate out, but are in a dynamic equilibrium state. The number of water molecules evaporated is equal to the number of water molecules returned from the air to the water, and the water temperature remains unchanged. From this, it can be seen that the drier the air in contact with water, the easier it is to evaporate and the easier it is to reduce the water temperature.
Q: Contents and steps of annual maintenance of cooling tower
A: 1. The surface of cooling tower frame and water basin shall be cleaned of dirt, and the filler shall be cleaned with clean water.
2. Check whether the cooling tower sprinkler system is blocked. If there are impurities, eliminate the blockage.
3. Check whether the water basin and floating ball system of the cooling tower are leaking. If there are problems, solve them.
4. Check whether all fasteners of the cooling tower are loose and lock the loose fasteners.
5. check the motor of the cooling tower, replace the grease in the motor, add oil to the bearing and replace the oil seal. During the adjustment of motor bearing, pay attention to make the magnetic gap uniform, and use instruments to detect, so as to make the current uniform during operation and prolong its service life. (Note: the motor bearing can be replaced every two years)
6. replace the lubricating oil of the reducer of the cooling tower, check whether the oil level is appropriate, add oil to the bearing and replace the oil seal. Disassemble the reducer and clean the internal parts every 10000 hours.
7. Check whether there is any accumulation of soil or scale on the fan of the cooling tower. If so, carefully remove the soil and scale to maintain the balance of the fan.
8. Check the tightness of the cooling tower belt and accurately adjust the motor belt to the best position to prolong the service life of the belt.
9. Brush the motor and reducer of the cooling tower with antirust paint. Check whether the galvanized parts of the cooling tower are damaged and corroded. If they are treated with antirust paint and anti-corrosion materials.
10. Comprehensively check the operation of the cooling tower: the fan shall rotate clockwise, the wind direction shall be upward, whether the fan operates stably, whether the rotating water distributor operates normally, whether the water distribution of the nozzle is uniform, whether the moisture-proof measures of the motor are tight, etc. After inspection, it can be determined that the maintenance is completed and delivered to Party A for use.
2. Check whether the cooling tower sprinkler system is blocked. If there are impurities, eliminate the blockage.
3. Check whether the water basin and floating ball system of the cooling tower are leaking. If there are problems, solve them.
4. Check whether all fasteners of the cooling tower are loose and lock the loose fasteners.
5. check the motor of the cooling tower, replace the grease in the motor, add oil to the bearing and replace the oil seal. During the adjustment of motor bearing, pay attention to make the magnetic gap uniform, and use instruments to detect, so as to make the current uniform during operation and prolong its service life. (Note: the motor bearing can be replaced every two years)
6. replace the lubricating oil of the reducer of the cooling tower, check whether the oil level is appropriate, add oil to the bearing and replace the oil seal. Disassemble the reducer and clean the internal parts every 10000 hours.
7. Check whether there is any accumulation of soil or scale on the fan of the cooling tower. If so, carefully remove the soil and scale to maintain the balance of the fan.
8. Check the tightness of the cooling tower belt and accurately adjust the motor belt to the best position to prolong the service life of the belt.
9. Brush the motor and reducer of the cooling tower with antirust paint. Check whether the galvanized parts of the cooling tower are damaged and corroded. If they are treated with antirust paint and anti-corrosion materials.
10. Comprehensively check the operation of the cooling tower: the fan shall rotate clockwise, the wind direction shall be upward, whether the fan operates stably, whether the rotating water distributor operates normally, whether the water distribution of the nozzle is uniform, whether the moisture-proof measures of the motor are tight, etc. After inspection, it can be determined that the maintenance is completed and delivered to Party A for use.
Q: Common formula for cooling tower selection
A: Common formula for selecting cooling tower with known basic conditions:
Cooling water volume = refrigerating capacity of main engine (kw) × one point two × one point two five × 861/5000(m3/h)
Cooling water volume = heat load of main condenser (kcal / h) × 1.2/5000(m3/h)
Cooling water volume = heat load of main condenser (m3 / h) × 1.2(m3/h)
Cooling water volume = refrigerating capacity of main engine (cooling ton) × 0.8(m3/h)
Cooling water volume = heat load of main evaporator (kcal / h) × one point five × 1.25/5000(m3/h)
Cooling water volume = heat load of main evaporator (m3 / h) × one point two × 1.25(m3/h)
Cooling water volume = heat load of main engine evaporator (cooling ton) × one point two × one point two five × 3024/5000(m3/h)
Note: the above: 1.2 is the selection allowance, and 1.25 is the condenser load factor.
For example, the refrigerating capacity of lithium bromide host per 1 million kcal is:
Working condition ①: 37.5/32/28, (cooling water flow: 300 ~ 330m3 / h) with 350-400 towers;
Working condition ②: 37 / 30 / 28, (cooling water flow: 248m3 / h) with 450 tower.
Cooling water volume = refrigerating capacity of main engine (kw) × one point two × one point two five × 861/5000(m3/h)
Cooling water volume = heat load of main condenser (kcal / h) × 1.2/5000(m3/h)
Cooling water volume = heat load of main condenser (m3 / h) × 1.2(m3/h)
Cooling water volume = refrigerating capacity of main engine (cooling ton) × 0.8(m3/h)
Cooling water volume = heat load of main evaporator (kcal / h) × one point five × 1.25/5000(m3/h)
Cooling water volume = heat load of main evaporator (m3 / h) × one point two × 1.25(m3/h)
Cooling water volume = heat load of main engine evaporator (cooling ton) × one point two × one point two five × 3024/5000(m3/h)
Note: the above: 1.2 is the selection allowance, and 1.25 is the condenser load factor.
For example, the refrigerating capacity of lithium bromide host per 1 million kcal is:
Working condition ①: 37.5/32/28, (cooling water flow: 300 ~ 330m3 / h) with 350-400 towers;
Working condition ②: 37 / 30 / 28, (cooling water flow: 248m3 / h) with 450 tower.
Q: Purchase conditions of cooling tower
A: 1. The specific design parameters of the cooling tower shall be subject to the parameter requirements of the air conditioning host in the design drawing
2. It must meet the design requirements of inlet and outlet water temperature, hourly cooling water volume under wet bulb temperature and ultra-low noise indicators. The supplier must provide the equipment model, specification, performance index, external dimension, dry weight, operating weight, noise index and other data calibrated by the manufacturer.
3. The manufacturing of cooling tower must comply with GB / t7190 1-2008 standard, the main technical requirements are as follows:
(1) The cooling capacity shall not be less than 95.0%
(2) The measured power consumption ratio shall not be greater than 0.035KW / (m) ³/ h).
(3) The bleaching rate shall not be greater than 0.015% of the nominal cooling water flow
(4) The noise level is ultra-low noise type C, and the nominal cooling water flow is 125 M ³/ H the noise index of the cooling tower shall not exceed 58.0db (a), and the nominal cooling water flow shall be 250m ³/ H the noise index of cooling tower shall not exceed 60.5db (a).
4. Cooling tower body
(1) The cooling tower body is an anti-seismic structure, and the specification, model and thickness of steel used for the structure shall comply with the provisions of relevant standards. All parts shall be subject to hot-dip galvanized surface treatment, and the connecting fasteners shall be stainless steel.
(2) The stiffness of the tower shall meet the requirements of relevant specifications, and shall meet the requirements of seismic fortification intensity of 7 in this area, and its wind resistance strength shall be more than 250kg / m2.
5. FRP parts
(1) It shall be made of glass fiber reinforced plastic (FRP) with corrosion resistance, weather resistance and impact resistance, and it is not allowed to contain talc and other impurities; The imported gel coat layer with good aging resistance and stability shall be adopted on the surface, and its thickness shall be controlled within the range of 0.3-0.5mm; The raw materials used shall comply with the provisions of relevant standards, and the resin content, curing degree, bending strength, Babbitt hardness and other indicators shall fully meet the requirements of the national standard of cooling tower; Flame retardant resin is required to be used, and its oxygen index detection value is ≥ 28. Other materials used on the surface of the tower shall also be flame retardant materials.
(2) The appearance gel coat layer of FRP body shall be uniform, with smooth surface, no crack and uniform color. There shall be no more than 3 bubbles with a diameter of 3-5mm on the outer surface of the tower within 1m2, and bubbles with a diameter of more than 5mm are not allowed. The inner surface of the lower tower shall be a resin rich layer with a resin content of more than 70%; The edge of the tower body shall be neat, the thickness shall be uniform, and there shall be no delamination. The cutting section shall be sealed with resin.
6. Fan
(1) The performance parameters of the fan shall meet the requirements of the design working conditions. The static balance test shall be conducted before the fan assembly, and the blades shall be positioned and numbered after balance.
(2) The matched motor and reducer shall be matched with the fan. The motor is fully enclosed outdoor type, with insulation grade above grade B and protection grade of 1p55 The brand and manufacturer shall be indicated, and the origin of imported motor shall be indicated.
(3) Reducer, shaft, bearing, belt and pulley are required to be high-quality parts, and the product brand, specification, model, material and manufacturer shall be indicated. The place of origin of imported parts shall be indicated.
(4) The fan blade shall have reliable strength, smooth surface, over uniform cross-section and no defects such as crack, notch and burr; On the surface of FRP fan blade, the visible bubble diameter shall not be greater than 3mm, and the number of bubbles in each 100mm area shall not exceed 3.
(5) the clearance between the blade and the inner wall of the air duct shall be uniform, and its value shall not be greater than 0.008 times the fan diameter.
(6) the fan drive bearing shall adopt external oil injection structure to facilitate daily maintenance; A reliable protective net shall be set above the fan to prevent foreign matters from entering the cooling tower.
7. Filler
(1) The cooling tower packing shall be flame retardant materials with high cooling efficiency and low ventilation resistance; It is forbidden to use recycled materials or part of recycled materials.
(2) During the installation of the filler, the gap shall be uniform, the top surface shall be flat, there shall be no collapse and lamination, the filler can bear 2.94kn per square meter, and the filler shall not be empty or broken.
8. Cooling tower water distribution system
(1) The cross flow tower should adopt the pool type water distribution with cover plate.
(2) The distribution tank shall be horizontal, the orifice shall be smooth, and the ponding depth shall not be less than 50mm.
(3) The water distribution shall be uniform.
9. The anti floating structure of the cooling tower shall be easy to load and unload, so as to facilitate the regular cleaning of the cooling tower packing.
10. The water make-up mechanism of the cooling tower shall be sensitive and reliable.
11. Provide product test reports and meet national inspection standards.
12. The patented technology adopted by the equipment shall have a written description, and the floating water index and energy-saving index shall have a detailed description.
13. The supplier shall provide the following documents with the product:
(1) Samples or product instructions: mainly including design wet bulb temperature, inlet and outlet tower water temperature, cooling water flow, air volume, motor power, standard point noise, main installation dimensions, basic dimensions, foundation load, installation and maintenance instructions; The thermal performance curve calculated according to the thermal test data shall be provided in the product sample or product manual for the user to determine the relevant parameters of the cooling tower under non-standard working conditions.
(2) Factory certificate.
(3) Details of vulnerable parts of the product.
(4) Packing list.
14. The service life of the cooling tower shall not be less than 15 years, and the warranty period is 2 refrigeration periods.
2. It must meet the design requirements of inlet and outlet water temperature, hourly cooling water volume under wet bulb temperature and ultra-low noise indicators. The supplier must provide the equipment model, specification, performance index, external dimension, dry weight, operating weight, noise index and other data calibrated by the manufacturer.
3. The manufacturing of cooling tower must comply with GB / t7190 1-2008 standard, the main technical requirements are as follows:
(1) The cooling capacity shall not be less than 95.0%
(2) The measured power consumption ratio shall not be greater than 0.035KW / (m) ³/ h).
(3) The bleaching rate shall not be greater than 0.015% of the nominal cooling water flow
(4) The noise level is ultra-low noise type C, and the nominal cooling water flow is 125 M ³/ H the noise index of the cooling tower shall not exceed 58.0db (a), and the nominal cooling water flow shall be 250m ³/ H the noise index of cooling tower shall not exceed 60.5db (a).
4. Cooling tower body
(1) The cooling tower body is an anti-seismic structure, and the specification, model and thickness of steel used for the structure shall comply with the provisions of relevant standards. All parts shall be subject to hot-dip galvanized surface treatment, and the connecting fasteners shall be stainless steel.
(2) The stiffness of the tower shall meet the requirements of relevant specifications, and shall meet the requirements of seismic fortification intensity of 7 in this area, and its wind resistance strength shall be more than 250kg / m2.
5. FRP parts
(1) It shall be made of glass fiber reinforced plastic (FRP) with corrosion resistance, weather resistance and impact resistance, and it is not allowed to contain talc and other impurities; The imported gel coat layer with good aging resistance and stability shall be adopted on the surface, and its thickness shall be controlled within the range of 0.3-0.5mm; The raw materials used shall comply with the provisions of relevant standards, and the resin content, curing degree, bending strength, Babbitt hardness and other indicators shall fully meet the requirements of the national standard of cooling tower; Flame retardant resin is required to be used, and its oxygen index detection value is ≥ 28. Other materials used on the surface of the tower shall also be flame retardant materials.
(2) The appearance gel coat layer of FRP body shall be uniform, with smooth surface, no crack and uniform color. There shall be no more than 3 bubbles with a diameter of 3-5mm on the outer surface of the tower within 1m2, and bubbles with a diameter of more than 5mm are not allowed. The inner surface of the lower tower shall be a resin rich layer with a resin content of more than 70%; The edge of the tower body shall be neat, the thickness shall be uniform, and there shall be no delamination. The cutting section shall be sealed with resin.
6. Fan
(1) The performance parameters of the fan shall meet the requirements of the design working conditions. The static balance test shall be conducted before the fan assembly, and the blades shall be positioned and numbered after balance.
(2) The matched motor and reducer shall be matched with the fan. The motor is fully enclosed outdoor type, with insulation grade above grade B and protection grade of 1p55 The brand and manufacturer shall be indicated, and the origin of imported motor shall be indicated.
(3) Reducer, shaft, bearing, belt and pulley are required to be high-quality parts, and the product brand, specification, model, material and manufacturer shall be indicated. The place of origin of imported parts shall be indicated.
(4) The fan blade shall have reliable strength, smooth surface, over uniform cross-section and no defects such as crack, notch and burr; On the surface of FRP fan blade, the visible bubble diameter shall not be greater than 3mm, and the number of bubbles in each 100mm area shall not exceed 3.
(5) the clearance between the blade and the inner wall of the air duct shall be uniform, and its value shall not be greater than 0.008 times the fan diameter.
(6) the fan drive bearing shall adopt external oil injection structure to facilitate daily maintenance; A reliable protective net shall be set above the fan to prevent foreign matters from entering the cooling tower.
7. Filler
(1) The cooling tower packing shall be flame retardant materials with high cooling efficiency and low ventilation resistance; It is forbidden to use recycled materials or part of recycled materials.
(2) During the installation of the filler, the gap shall be uniform, the top surface shall be flat, there shall be no collapse and lamination, the filler can bear 2.94kn per square meter, and the filler shall not be empty or broken.
8. Cooling tower water distribution system
(1) The cross flow tower should adopt the pool type water distribution with cover plate.
(2) The distribution tank shall be horizontal, the orifice shall be smooth, and the ponding depth shall not be less than 50mm.
(3) The water distribution shall be uniform.
9. The anti floating structure of the cooling tower shall be easy to load and unload, so as to facilitate the regular cleaning of the cooling tower packing.
10. The water make-up mechanism of the cooling tower shall be sensitive and reliable.
11. Provide product test reports and meet national inspection standards.
12. The patented technology adopted by the equipment shall have a written description, and the floating water index and energy-saving index shall have a detailed description.
13. The supplier shall provide the following documents with the product:
(1) Samples or product instructions: mainly including design wet bulb temperature, inlet and outlet tower water temperature, cooling water flow, air volume, motor power, standard point noise, main installation dimensions, basic dimensions, foundation load, installation and maintenance instructions; The thermal performance curve calculated according to the thermal test data shall be provided in the product sample or product manual for the user to determine the relevant parameters of the cooling tower under non-standard working conditions.
(2) Factory certificate.
(3) Details of vulnerable parts of the product.
(4) Packing list.
14. The service life of the cooling tower shall not be less than 15 years, and the warranty period is 2 refrigeration periods.
Q: Precautions during operation of cooling tower
A: The cooling tower evenly sprays the circulating cooling water on the packing of the cooling tower to increase the residence time of the cooling water on the packing, so as to increase the contact time with the air and form additional hair. A cooling tower device that then achieves the effect of cooling. When we understand its operation principle, we will have a general understanding of it. When we repair the cooling tower, we will know what is wrong. My article explains to you the matters needing attention when the cooling tower works:
1. Check the oil level of the reducer of the cooling tower at an interval of one month to prevent oil shortage. In summer, add oil with high viscosity. After the first operation for 20 days, empty the butter and inject new oil.
2. The cooling tower fan shall be installed in strict accordance with the factory instructions. It is a circuit. If it is not wired according to the manufacturer, it will reverse and the motor speed cannot be adjusted.
3. If the quality of circulating water and make-up water is poor, water quality stabilization measures shall be taken, side filters shall be set, and sterilization and algae killing measures shall be taken if necessary.
4. FRP is a combustor, so open fire shall not be used during maintenance of cooling tower If open fire is used, corresponding safety measures must be taken and approved by the fire and safety department, with full-time firefighters Fire fighting facilities are present.
1. Check the oil level of the reducer of the cooling tower at an interval of one month to prevent oil shortage. In summer, add oil with high viscosity. After the first operation for 20 days, empty the butter and inject new oil.
2. The cooling tower fan shall be installed in strict accordance with the factory instructions. It is a circuit. If it is not wired according to the manufacturer, it will reverse and the motor speed cannot be adjusted.
3. If the quality of circulating water and make-up water is poor, water quality stabilization measures shall be taken, side filters shall be set, and sterilization and algae killing measures shall be taken if necessary.
4. FRP is a combustor, so open fire shall not be used during maintenance of cooling tower If open fire is used, corresponding safety measures must be taken and approved by the fire and safety department, with full-time firefighters Fire fighting facilities are present.
Q: What is cooling tower fill? And its function
A: For factories in summer, there is a very important thing-cooling tower filler. What is the main thing of cooling tower filler? It is mainly a material used in cooling towers. Speaking of cooling towers, it can also be understood from the literal meaning as a cooling effect. Today, let's explore what cooling tower filler is?
Filler is the most important part of the cooling tower. Its efficiency depends on the complete contact between the cooling water and the air in the filler. The filler has excellent properties of temperature resistance of 50℃~68℃, aging resistance, UV resistance and long life.
In short, the role of the filler in the cooling tower is to increase heat dissipation, increase the residence time of cooling water, increase the heat exchange area and increase heat exchange. But it is not to fill the tower with things that need to be cooled. It is a facility to cool the hot fluid to an effective temperature. Waste heat generated in industrial production or refrigeration processes is usually taken away by cooling water. The role of the cooling tower is to exchange heat between the cooling water carrying waste heat and the air in the tower, so that the waste heat is transferred to the air and dispersed into the atmosphere.
Cooling tower filler is used as the key core of cooling circulating water and heat dissipation treatment in industrial production. Its refrigeration pipeline is the medium of the entire central air-conditioning equipment. In my country's industrial manufacturing industry, it affects the cost and efficiency of my country's industrial manufacturing. Improper operation of cooling towers in industrial manufacturing can lead to risks such as mechanical equipment, untimely heat dissipation, stagnation of production and processing, and excessive water temperature. Therefore, cooling tower fillers must be cleaned regularly and maintained.
Filler is the most important part of the cooling tower. Its efficiency depends on the complete contact between the cooling water and the air in the filler. The filler has excellent properties of temperature resistance of 50℃~68℃, aging resistance, UV resistance and long life.
In short, the role of the filler in the cooling tower is to increase heat dissipation, increase the residence time of cooling water, increase the heat exchange area and increase heat exchange. But it is not to fill the tower with things that need to be cooled. It is a facility to cool the hot fluid to an effective temperature. Waste heat generated in industrial production or refrigeration processes is usually taken away by cooling water. The role of the cooling tower is to exchange heat between the cooling water carrying waste heat and the air in the tower, so that the waste heat is transferred to the air and dispersed into the atmosphere.
Cooling tower filler is used as the key core of cooling circulating water and heat dissipation treatment in industrial production. Its refrigeration pipeline is the medium of the entire central air-conditioning equipment. In my country's industrial manufacturing industry, it affects the cost and efficiency of my country's industrial manufacturing. Improper operation of cooling towers in industrial manufacturing can lead to risks such as mechanical equipment, untimely heat dissipation, stagnation of production and processing, and excessive water temperature. Therefore, cooling tower fillers must be cleaned regularly and maintained.