The air cooler is designed to lower the temperature of gases or various liquids. These devices are involved mainly in technological processes. However, in industry they can also be found. When using a cooling apparatus, much depends on the pressure of the medium. The maximum threshold averages 16 MPa. In some cases, devices are used under vacuum. In this case, the residual pressure should not be lower than 650 Pa. The permissible temperature depends on the type of cooling unit.
What types are there?
By design, the cooling apparatus is divided into horizontal and vertical. There are still zigzag patterns. They can be installed with one or two fans. For cooling viscous substances, there is a separate type, which is divided into subspecies (low-flow, as well as block-modular). For compressors, cooling units are distinguished with and without a recirculation system.
Cooling devices "AVG"
The air cooler "AVG" is involved to condense and lower the temperature of vaporous and liquid means. It is used most often in the petrochemical industry. The design of this device is quite simple. It consists of an electric motor and pipe sections. Additionally there is a drive for a fan.
To adjust the air flow there are blinds. On some models, the flaps rotate automatically. There are 3 sections in the apparatus. The diameter of the fan wheel is within 3 m. The electric motor power is 37 kW. In some models, this parameter is 30 kW. The fan wheel speed is quite large. With a power of 37 kW, more than 300 rpm is performed. The coefficient of finning of pipes is 20. In one section, there can be from 4 to 8 rows of pipes. As a rule, they are installed lid type. The average pipe length in a section is 4 m.
What is the difference between devices for viscous products?
These devices use special bimetallic pipes. In this case, the viscosity index of the substance should be no more than 10 m 2 / s. These devices are most suitable for oil refineries. Their finning ratio is low. Only one fan is installed on this air-cooling unit.
The diameter of the carrier pipe is 38 mm. In this case, the sections are mounted in a special way. This is necessary so that the fan drive is in a separate frame. At the same time, its wheel rotates in the cavity of the collector. As a result, air passes between the pipes. The equipment of this cooling device depends on the manufacturer. If necessary, a humidifier can be applied to the device.
Blinds usually work automatically. However, a manual rotary damper is provided by the manufacturer. If we talk about the characteristics, then the pressure of the apparatus is kept at 37 MPa. There are three sections in total. The diameter of the fan is 2.8 m. The power of the electric motor ranges from 20 to 35 kW. The average wheel speed is 400 rpm. Coefficient of finning of pipes 7.8. In one section there can be up to eight pipes. The case is made of B2 steel . Sections are installed lid type. Pipes come in 4 as well as 8 m.
Description of the zigzag type apparatus "AVZ"
Zigzag type air cooler "AVZ" is suitable for cooling gaseous substances. Such devices are used only in the petrochemical industry. Their difference is the presence of six sections. They are made of bimetallic pipes. As the name implies, they have a zigzag shape. In this case, the angle is quite sharp. To fix the sections, special horizontal stops are provided.
The lower platform is pretty solid. The fan drive is mounted on a separate frame. The device wheel rotates in the manifold. In some cases, such devices may be equipped with a recirculation system. In this case, the blinds are located in the upper as well as in the lateral parts of the device. In this case, overcooling of the substance is prevented. This is especially true in the winter season. Directly fans can also be installed different. Some manufacturers produce them from composite materials. In this case, they are more durable.
The heat transfer area is 2650 to 8480 square meters. m. Pressure is kept at 5 MPa. The fan is installed with a diameter of 5 m. The electric motor power ranges from 30 to 70 kW. In total, one wheel is provided in the design. Its average rotation speed is 200 rpm. An average section consists of four pipes. Blinds withstand pressure only up to 0.6 MPa. The length of the pipes is 4 m.
Dual fan units
These types of air coolers are used, as a rule, in related industries. However, they cope well with the condensation of vaporous substances. It is also possible to cool the liquid in the apparatus. There are six pipe sections in total. They are located on a zigzag frame. Pipes are mainly mounted bimetallic. Horizontal supports in this cooling unit are provided. A drive with a wheel is mounted on the frame. The fan wheels are located in the collector cavity.
A humidifier is usually included. The calculation of the air cooling apparatus is based on the density indicator. Manual blinds are provided. There are panels with barriers on the side sections. They are located at the bottom of the device. Electric motors generally have a speed converter. All this reduces the power consumption of the device. The air line is automatically adjusted. In this case, the angle of the blades changes quite smoothly. The fans are easy to maintain. According to the characteristics of the cooling apparatus with two fans are not too different from other types.
The average length of the pipe is 4 m. In this case, the sections are installed of the roof type. The tube finning ratio ranges from 9 to 20. The fan wheels rotate at a maximum speed of 400 rpm. Moreover, the electric motor power is 37 kW. The diameter of the wheel is 2.8 m. The operating pressure is at around 6 MPa. The heat transfer area is 3450 per 11,400 square meters. m
Low-threaded type of devices "AVM"
"AVM" air coolers are used to cool liquids. They are most in demand at various industrial enterprises. Their designs can be horizontal or vertical. In this case, a section in the device is provided for one. It consists of finned tubes. The fan is axial type. He pumps air quite quickly. In this case, the flow passes along the pipes.
Electric motors for these models are special. They differ from other devices in explosion-proof execution. The blinds of the device can be manual or automatic. An air heater is also provided. A recirculation chamber is also present. The supporting structure of the cooling unit is very durable. It withstands seismicity of up to nine points.
Characteristics of devices "AVM"
The heat exchange surface area is 105 per 375 sq. m. In this case, the pressure is maintained at a maximum of 4 MPa. Electric motor power is 3 kW. A fan wheel averages around 1,500 rpm. The length of one heat exchanger pipe is 1.5 m. In total, the section has 8 rows. The finning coefficient is at level 20. Frames are made of steel grade "B1" or "B2". This air-cooling unit weighs 4200 kg.
Block-modular cooling device "ABO"
The air cooler "ABO" is used in technological processes for the condensation of gaseous substances. It is used in the oil refining and petrochemical industries. The design of the models is horizontal. Thanks to this, the fans are installed in the lower part. Additionally, there is a special box on the frame. It is necessary for air injection.
In sections rolled pipes are used. Blinds are installed for air recirculation. There are also heaters that will prevent the substance from overcooling. In winter, this problem is especially relevant. There are a lot of modifications of this type of apparatus. The average area of heat transfer pipes is 595 per 1565 square meters. m. At the same time, a maximum of 1795 devices are produced per 4735 square meters. m. The diameter of the fan wheel is 1.6 m.
There is one section in the apparatus. The power of a low-speed electric motor can reach 15 kW. The number of wheels in the device depends on the modification. On average, there are 6 pipes per section. The fan wheel makes over 700 revolutions in one minute. The length of the section can reach 12 m. The heat exchanger "AVO" air-cooling apparatus has only a chamber type.
Description of devices with recirculation
These devices are used to lower the temperature of sulfur-containing gases. At the same time, they are equipped with input and output collectors. Most often, gas air cooling devices can be found at booster compressor stations. They are also actively exploited on gas pipelines. They are single and joined.
In the first embodiment, the device operates independently. Docking devices are usually connected in a row to increase power. Sections in them are installed horizontally. They consist of bimetallic pipes. At the same time, air is forced by the fan. It is installed, as a rule, of the axial type. There is a fan in the lower part of the cooling unit, on the frame. Next to it there is a low-speed electric motor.
In cold climates, air-cooled gas chillers feel great. Fan wheels are usually made of composite materials. A speed converter is provided. At the same time, electricity consumption is quite moderate. All this indicates the economy of this type of device. The angle of the blades can be adjusted manually. In general, the fans are very simple to maintain. A trolley can be supplied with the device. It is necessary to remove the electric motor. At the same time, wheel repair can also be done with it.
What are the characteristics of recirculation apparatus?
The heat exchange area is 9930 square meters. m. The design pressure is 7.5 MPa. The calculation of the air cooling apparatus is based on the pressure indicator. In total, the device has 3 sections. The diameter of the fan wheel is exactly 5 m. The electric motor power is 37 kW. The average rotation speed reaches 250 rpm. The coefficient of finning of pipes is 20. A welded chamber is installed in CT20 class. There are 6 pipes in the section. The collector and plugs in the cooling apparatus are made of steel.
Cooker hoods
This air cooler is used to condense water vapor. As a rule, it is an integral part of the turbine unit. 6 axial fans are located on it. Water vapor enters the collector directly through pipes. In a special chamber, it condenses.
Steam is removed using a fitting. All residues fall into the upper section. In it, the condensation process is completed. Sometimes sections can freeze. To avoid such problems, the devices have blinds. They are located on all sides. Manual adjustment of the flaps is naturally possible. In general, the device is difficult and quite difficult to maintain.