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What is rotary valve

Rotary valve, also known as unloading valve and star unloader, is a mechanical device that changes the valve from the open position to the closed position by rotating a rotating component such as a rotating baffle.
A rotary valve is a device that achieves fluid control by rotating a valve. In a rotary valve, the opening and closing, regulation, distribution, etc. of the fluid in the pipeline are controlled through the rotation of the valve. Therefore, the rotary valve is often called a revolving door. Rotary valves usually consist of a valve body, a valve shaft and a valve sealing ring.

Rotary valve working principle

The working principle of the rotary valve is mainly based on its design structure and working mechanism. The rotary valve usually consists of a rotor blade.
When the material in the upper bin falls by its own weight and fills the space of the rotor blade, as the blade rotates, the material is taken to the lower outlet and discharged, thereby achieving continuous feeding and unloading. function of the material.
This design is particularly important in pneumatic conveying systems because it can not only supply materials, but also lock the air flow.
Through the low-speed rotation of the rotor and the extremely small gap between the rotor and the inner cavity of the housing, it effectively prevents the reverse flow of the air flow, thereby maintaining The air pressure in the system is stable and the materials are discharged normally.
The self-cleaning rotary valve is improved on the basis of ordinary rotary valves. By adding a cleaning blade (scraper), it can automatically remove the residual material on the rotor while dosing the material quantitatively.
It is especially suitable for sticky and easy-to-stick valves. block of special materials. Its working principle involves the coordinated work of two upper and lower rotors: the upper rotor is equipped with blades for quantitative feeding, while the lower rotor is equipped with a cleaning blade, which uses the difference in rotational speed of the upper and lower rotors to achieve self-cleaning while quantitatively feeding.
The working principle of the eccentric rotary valve is to use an eccentrically rotating sector-shaped ball valve to open and close the valve through the engagement and separation of the eccentric ball crown and the valve seat. When opening, the ball core separates from the valve seat; when closing, the ball core gradually contacts the valve seat, exerting a compressing force on the valve seat.

Rotary valve diagram

What is a rotary valve used for?

Specific uses for rotary valves include:
‌Unloading‌: In the negative pressure pneumatic conveying system, the rotary valve is installed under the cyclone separator and dust collector as an unloader to unload materials.
‌Air lock: Through low-speed rotation and a very small gap between the rotor and the inner cavity of the housing, the rotary valve effectively prevents the reverse flow of air and keeps the air pressure in the system stable.
Feeding‌: In the pneumatic conveying system, the rotary valve continuously supplies material to ensure the normal discharge of materials‌.
‌Prevent clogging‌: The rotary valve can transport materials evenly and continuously, prevent gas and solid materials from accumulating in the pipeline, and avoid blockage and leakage‌.

11 10 月 2024

Rotary valve feeder

The rotary feeder is also called a rotary valve, a star feeder, and an air lock.
The usual structure of a rotary feeder is that a rotor with several blades rotates in a cylindrical casing. Materials fall from the upper hopper and are filled.
In the space between the blades, it is discharged as the blades rotate to the lower part.
There is a pressure equalizing exhaust port on the side of the body, which can discharge the high-pressure gas brought by the rotation of the impeller, reducing the phenomenon of gas pushing and conducive to the smooth flow of materials.
The drop is one of the main components of the pressure-feeding and suction-feeding pneumatic conveying systems, and the rotary feeder type. It can feed materials into the clinker pipe evenly and continuously, and in the separation and dust collection part of the system, it It also has the functions of unloader and air lock.

Rotary feeder working principle

The working principle of the rotary feeder is that the driving device drives the spiral scraper or the turntable to rotate.
The material is pushed and frictioned by the spiral scraper or centrifugal force, and is continuously transported or transported upward along the movement direction of the spiral scraper or turntable.
It is thrown away from the turntable and finally discharged from the discharge port or falls freely in the air to realize the transportation and diffusion of materials.
Rotary feeder, also known as rotary feeder, is a commonly used material conveying equipment and is widely used in mining, building materials, chemical industry, metallurgy and other industries.
It uses a rotating spiral scraper or turntable to transport materials from the bottom of the container or the turntable to the upper discharge port or throw them away from the turntable to achieve continuous feeding and transportation of materials.
This kind of equipment consists of spiral scrapers, bearings, transmission devices, etc. Its working principle is simply to use friction and pushing to transport materials along the movement direction of the spiral blades or turntable through the rotating spiral blades or turntable. .
Specifically, when the drive device is started, it drives the spiral scraper or turntable to rotate. Material falls from the upper hopper and fills the space in the spiral scraper or turntable. As it rotates, the material is pushed and rubbed, and is continuously transported upward along the movement direction of the spiral scraper or turntable.
When the material reaches the edge of the turntable, it will be discharged from the discharge port, or it will fall freely in the air to realize the transportation and diffusion of the material. This design not only ensures the uniform transportation of materials, but also reduces the phenomenon of gas ejection, which is conducive to the smooth falling of materials.
In addition, the rotary feeder also has the characteristics of simple structure and easy maintenance. It can be customized according to different production needs, so it plays an important role in the production line.

Rotary feeder diagram

11 10 月 2024

Diesel Roots Blower

The diesel engine provides power and transmits the power to the Roots blower through the transmission device to drive it to operate.
There are two intermeshing rotors inside the Roots blower. During operation, these two rotors continuously change the gas volume to achieve the suction, compression and discharge of gas.
Due to its simple structure and smooth operation, diesel Roots blower has become the first choice in many industrial situations.

Roots blower diagram

Roots blower uses

‌Roots blowers‌ are widely used in many industries and fields, mainly including:
‌Sewage treatment‌: In the sewage treatment industry, roots style blowers are widely used in aeration, stirring, mixing and other aspects to ensure the smooth progress of the sewage treatment process.
‌Pneumatic conveying system‌: roots style blowers are used to transport feed, lime powder, monosodium glutamate, soybean skin, silica and other powdery materials, as well as grain suction machines or crane suction vacuum pumps in grain transportation to ensure the effectiveness of materials transmission.
‌Aquaculture‌: In aquaculture, roots style blowers use micropore aeration technology to oxygenate water quality and improve breeding efficiency.They are important equipment in the aquaculture industry.
‌Coal chemical industry‌: In the coal chemical industry, Roots blowers are used in sewage treatment and different processes, playing an important role in improving production efficiency and product quality‌.
‌Dust removal industry‌: Roots blowers are also used in the dust removal industry, such as desulfurization, denitrification, dust removal, etc., to ensure the effective treatment of industrial flue gas and waste gas.
‌Grain processing, flour mills, food factories‌: used in transportation, drying, cooling, dust and other links to ensure the smooth progress of the food processing process‌.
‌Paint and Coating Industry‌: Used for ventilation, dust removal and waste gas treatment to ensure the safety and health of the working environment.
‌Mining, quarrying, and mineral processing industries‌: used in emissions, exhaust, gas transportation, drying and other links to ensure environmental control and safety during the development of mineral resources‌.
‌Pharmaceutical Industry‌: In the pharmaceutical industry, Roots blowers are used in pharmaceutical processing, chemical reactions and other aspects, such as laboratory ventilation equipment, to ensure the safety and efficiency of the pharmaceutical production process‌.

Roots blower specifications

Roots blower pressure range

According to different usage requirements, the pressure of the roots blower fan can be adjusted between 9.8kpa and 200kpa.Within this pressure range, the roots blower fan can work normally and meet various process requirements.Specifically, the pressure range of roots blower fan includes:
‌Low pressure range‌: The pressure is lower than 58.8kpa, including 9.8kpa to 58.8kpa.This type of fan usually uses air cooling, and is mostly designed with a single oil tank.
‌Medium pressure range‌: The pressure is between 58.8kpa and 98kpa.This type of fan requires water cooling, and most of them are designed with double oil tanks.
‌High pressure range‌: When the pressure exceeds 98kpa, especially when it exceeds 140kpa, double-stage pressure boosting technology is required to ensure stable operation of the fan under high pressure.

Roots blower company

Since its establishment in the early 1990s, Longgu Heavy Industry has become a diversified machinery enterprise integrating fan and pneumatic conveying equipment system engineering. Our company has advanced computer-aided design and manufacturing, CNC machining technology, and adopts information technologies such as computer-aided design and CAPPCT to improve product design and manufacturing accuracy and shorten the design and manufacturing cycle.
Shandong Longgu Heavy Industry Machinery Co., Ltd. has imported advanced and high-precision machining equipment from many countries, including fully automatic machining centers, CNC boring and milling machines, and dynamic balancing instruments. It has a high-level, large-scale, and modern mechanical processing and manufacturing workshop.
The company has completed the implementation and control of its internal quality management system, achieving independent quality control of products from research and development design to finished product delivery. It has established and improved a full process self-control system from design and production to quality, installation, and service, providing sufficient basis and reliable guarantee for the stability and durability of products.
We have cooperated with higher education institutions such as Shandong University, Shandong University of Technology, and Southwest University of Technology to strengthen the research and development of key core technologies. We have overcome technical difficulties and developed new products such as diesel engine driven Roots blowers, water-cooled dual tank Roots blowers, and low-noise Roots blowers, filling multiple industry gaps.
At present, our company’s main products include LGSR three leaf Roots blower, LGSR-V Roots vacuum pump, LGSR-H high-pressure blower series, bipolar series high-pressure, gas pressurized explosion-proof, pneumatic conveying series fans, steam compressors, LGMJ dense series fans, rotary fans, centrifugal fans, etc.
Our company’s products are widely used in industries such as sewage treatment, pneumatic conveying, vacuum packaging, grain processing, electricity, petrochemicals, cement, mining, and special gas pressurized conveying.
We have close cooperative relationships with top domestic enterprises such as Sande Group, COFCO Group, and Shanshui Cement. Our company’s sales outlets and after-sales service centers are located throughout the country and exported to countries such as Malaysia, India, Kyrgyzstan, Nigeria, etc.

11 10 月 2024

rotary valve

What is the rotary valve?

A rotary valve is a mechanical device that controls fluid regulation by rotating parts such as a rotating baffle to change the valve from the open position to the closed position. ‌‌
The working principle of the rotary valve is based on the rotor with several blades rotating in the cylindrical casing. The material falls from the upper hopper, fills the space between the blades, and is discharged as the blades rotate.
This kind of equipment usually consists of a rotor, a casing, a seal, a motor, a reducer, etc., and can achieve uniform and continuous material transportation.
Rotary valves are widely used in industry, especially in pneumatic conveying systems. They can evenly and continuously supply materials to the feeding pipe. They are suitable for positive or negative pressure pneumatic conveying systems, pulse dust removal equipment, precision feeding and other occasions. .
The rotary valve has the characteristics of compact structure, beautiful appearance, good air locking performance, stable operation, uniform blanking, light weight and energy saving. It can play the role of feeding and locking the air flow, effectively preventing the reverse flow of the air flow and ensuring the safety of the system. Stable air pressure and normal discharge of materials.

Rotary valve working principle

‌The working principle of the rotary valve‌ is mainly based on its design structure and working mechanism. The rotary valves usually consists of a rotor blade. When the material in the upper bin falls by its own weight and fills the space of the rotor blade, as the blade rotates, the material is taken to the lower outlet and discharged, thereby achieving continuous feeding and unloading. function of the material. This design is particularly important in pneumatic conveying systems because it can not only supply materials, but also lock the air flow. Through the low-speed rotation of the rotor and the extremely small gap between the rotor and the inner cavity of the housing, it effectively prevents the reverse flow of the air flow, thereby maintaining The air pressure in the system is stable and the materials are discharged normally.
The self-cleaning rotary valve is improved on the basis of ordinary rotary valves. By adding a cleaning blade (scraper), it can automatically remove the residual material on the rotor while dosing the material quantitatively. It is especially suitable for sticky and easy-to-stick valves. block of special materials. Its working principle involves the coordinated work of two upper and lower rotors: the upper rotor is equipped with blades for quantitative feeding, while the lower rotor is equipped with a cleaning blade, which uses the difference in rotational speed of the upper and lower rotors to achieve self-cleaning while quantitatively feeding. .
The working principle of the eccentric rotary valve is to use an eccentrically rotating sector-shaped ball valve to open and close the valve through the engagement and separation of the eccentric ball crown and the valve seat. When opening, the ball core separates from the valve seat; when closing, the ball core gradually contacts the valve seat, exerting a compressing force on the valve seat.
The working principle of the rotary valves involves many aspects such as material filling, rotary conveying, air flow control, etc. Different types of rotary valves (such as self-cleaning rotary valves, eccentric rotary valves) have different implementation methods, but they are all designed to improve the quality of materials. Conveying efficiency and system stability.

Rotary valve diagram

What is the function of a rotary control valve?

The main functions of the rotary valve include unloading and air locking. ‌‌
The rotary valve plays an important role in the negative pressure pneumatic conveying system, and its main functions can be summarized as two points: unloading and air locking. The discharge performance is directly related to the air locking performance of the rotary valve, which is particularly important in negative pressure pneumatic conveying systems.
The rotary valve is usually installed below the cyclone separator, dust collector or cyclone dust collector and is used as an unloader to ensure the smooth operation of the system and the effective transportation of materials. In addition, the rotary valve also has functions such as cut-off, diversion, pressure stabilization, and flow diversion, which further expands its diversity and flexibility in industrial applications.

10 10 月 2024

Rotary feeder

The usual structure of a rotary feeder is that a rotor with several blades rotates in a cylindrical casing.
Materials fall from the upper hopper and are filled. In the space between the blades, it is discharged as the blades rotate to the lower part.
There is a pressure equalizing exhaust port on the side of the body, which can discharge the high-pressure gas brought by the rotation of the impeller, reducing the phenomenon of gas pushing and conducive to the smooth flow of materials.
The drop is one of the main components of the pressure-feeding and suction-feeding pneumatic conveying systems, and the rotary feeder type.
It can feed materials into the clinker pipe evenly and continuously, and in the separation and dust collection part of the system, it It also has the functions of unloader and air lock.

Rotary feeder working principle

The working principle of the rotary feeder is that the driving device drives the spiral scraper or turntable to rotate.
The material is pushed and frictioned by the spiral scraper or centrifugal force, and is continuously transported upward or thrown away along the movement direction of the spiral scraper or turntable.
From the turntable, it is finally discharged from the discharge port or falls freely in the air to realize the transportation and diffusion of materials. ‌‌

Rotary feeder diagram

What is the purpose of a rotary feeder?

The main uses of rotary feeders include the following aspects:
‌Mining, building materials, chemical industry, metallurgy and other industries‌: In these industries, rotary feeders are used to continuously transport granular, powdery and block materials to ensure the stable operation of the production line‌.
‌Dust removal system‌: Rotary feeder is often used as an important part of the dust removal system, especially suitable for conveying dust and small particle materials‌.
‌Electronic industry, machinery industry and pharmaceutical industry‌: In these industries, rotary feeders are used for material supply in manufacturing and assembly processes, such as the production of electronic components, mechanical equipment and medical equipment.

10 10 月 2024

types of centrifugal fan

Types of centrifugal fan

‌The types of centrifugal fans mainly include the following: single-suction centrifugal fans, double-suction centrifugal fans, high-pressure centrifugal fans, static pressure box-type centrifugal fans and medium-pressure centrifugal fans‌. These types are suitable for a variety of different work environments and needs depending on their structure and purpose.
‌Single-suction centrifugal fan‌: Also known as front-suction centrifugal fan, it is suitable for transporting general gases and has a small air volume range.
‌Double-suction centrifugal fan‌: Also known as rear-suction centrifugal fan, it can be used under conditions of high pressure, large air volume, and small starting torque.
‌High-pressure centrifugal fan‌: mainly used to transport high-pressure gas, such as blowers, compressors, etc.
‌Static pressure box-type centrifugal fan‌: often used to eliminate noise and vibration during work and increase air volume and wind pressure.
‌Medium-pressure centrifugal fan‌: suitable for transporting gases with high dust content, high flue gas temperature or condensation water, etc.

Centrifugal fan working principle

The core working principle of a centrifugal fan is to use a high-speed rotating impeller to accelerate the gas, and then convert the kinetic energy of the gas into pressure energy (potential energy) by decelerating and changing the flow direction. ‌
This process mainly occurs in ‌single-stage centrifugal fans. The gas enters the impeller from the axial direction, changes to the radial direction when flowing through the impeller, and then enters the diffuser. In a diffuser, a change in the direction of gas flow causes deceleration, which converts the kinetic energy of the gas into pressure energy.
The increase in pressure occurs mainly in the impeller, followed by the expansion process. In multi-stage centrifugal fans, a refluxer is used to direct the airflow into the next impeller, thereby generating higher pressure. ‌

types of centrifugal fan

Centrifugal fan application

‌Industrial Manufacturing‌: Centrifugal fans are used in many industrial environments, such as ‌steel metallurgy, ‌chemical industry, ‌mining, etc. In these industries, fans are usually used to strengthen air supply, exhaust, refrigeration and hot air systems. Especially in harsh environments such as high temperature, corrosion, dust, etc., centrifugal fans play an irreplaceable role.
‌‌Environmental protection equipment‌: Centrifugal fans are also widely used in environmental protection equipment, such as ‌sewage treatment, ‌exhaust gas purification, etc. At the same time, centrifugal fans also play an important role in dust removal equipment, incineration equipment and advanced physical noise reduction equipment.
‌Construction equipment‌: In the construction field, centrifugal fans are used in air conditioning, ventilation, hot air and other fields. Through the air supply and exhaust system, they realize the circulation and flow of air and promote the convection and ventilation of indoor air.
‌Temperature control‌: Centrifugal fans can change the ambient temperature by blowing air, so they have important uses in heating, ventilation, air conditioning, drying and other temperature regulation equipment.
‌Air purification‌: In special environments such as laboratories, operating rooms and other places that have strict requirements on air quality, centrifugal fans can be used for air filtration and purification.
‌Agricultural cultivation‌: In agricultural production, centrifugal fans are used to provide a stable air environment for greenhouse plant growth, animal feeding, etc.
‌Transportation equipment‌: In transportation equipment such as trains and ships, centrifugal fans are also used for air circulation.
‌‌Food Processing‌: In the food processing industry, centrifugal fans are also very commonly used, such as drying equipment, cooling equipment and other food processing technology equipment.

Which type of centrifugal fan is the most efficient?

Forward curved plate centrifugal fans have the highest efficiency. ‌Forward curved plate centrifugal fans have high efficiency and small size, and are suitable for smaller air volumes and wind pressures. Therefore, among all types of centrifugal fans, forward curved plate centrifugal fans have the highest efficiency‌.
The high efficiency of the forward curved plate centrifugal fan is mainly due to its design features. Its impeller rotates in the same direction as the gas flow, which can maximize the use of kinetic energy and reduce energy loss. In addition, the compact structure of the forward curved plate centrifugal fan makes the air flow smoother when passing through the impeller, further improving efficiency.

9 10 月 2024

what are centrifugal fans

What are centrifugal fans

‌Centrifugal fan is a mechanical device that relies on mechanical energy to increase gas pressure and transport it out. It is widely used in various fields such as energy, environment, and aviation. It is one of the main energy-consuming equipment in industrial and agricultural production. ‌
The centrifugal fan is a type of impeller machinery. Its working principle is to form a negative pressure inside the fan through the rotation of the impeller, sucking in external air and expelling the fan through the impeller flow channel and volute. The centrifugal fan is mainly composed of casing, impeller, shaft, collector, exhaust port, bearing box, coupling, pulley and base.

what are centrifugal fans

Centrifugal fan working principle

The core working principle of a centrifugal fan is to use a high-speed rotating impeller to accelerate the gas, and then convert the kinetic energy of the gas into pressure energy (potential energy) by decelerating and changing the flow direction. ‌This process mainly occurs in ‌single-stage centrifugal fans. The gas enters the impeller from the axial direction, changes to the radial direction when flowing through the impeller, and then enters the diffuser. In a diffuser, a change in the direction of gas flow causes deceleration, which converts the kinetic energy of the gas into pressure energy. The increase in pressure occurs mainly in the impeller, followed by the expansion process. In multi-stage centrifugal fans, a refluxer is used to direct the airflow into the next impeller, thereby generating higher pressure. ‌
The workflow of the centrifugal fan includes the following key steps:
‌Gas entry‌: The airflow enters the blade space from the axial direction of the fan.
‌Acceleration‌: Driven by the impeller, the gas rotates with the impeller and increases energy under the action of inertia.
‌Centrifugal force action‌: The gas obtains centrifugal force driven by the impeller and leaves the impeller in the radial direction.
‌Diffusion and deceleration‌: When gas enters the diffuser, the change in flow direction causes deceleration. This deceleration converts the kinetic energy of the gas into pressure energy.
‌Exhaust gas‌: After passing through the diffuser, the gas is discharged from the fan and has a certain pressure.
The structure of a centrifugal fan includes a casing, a main shaft, an impeller and other components. The impeller is the main component that generates wind pressure and transmits energy. The casing is used to introduce and discharge gas, and at the same time convert part of the kinetic energy of the gas into pressure energy.

what are centrifugal fans

Types of centrifugal fans

‌The types of centrifugal fans mainly include the following: single-suction centrifugal fans, double-suction centrifugal fans, high-pressure centrifugal fans, static pressure box-type centrifugal fans and medium-pressure centrifugal fans‌. These types are suitable for a variety of different work environments and needs, depending on their structure and purpose.
Single-suction centrifugal fan‌: Also known as front-suction centrifugal fan, it is suitable for transporting general gases and has a small air volume range.
‌Double-suction centrifugal fan‌: Also known as rear-suction centrifugal fan, it can be used under conditions of high pressure, large air volume, and small starting torque.
‌High-pressure centrifugal fan‌: Mainly used to transport high-pressure gas, such as blowers, compressors, etc.
‌Static pressure box-type centrifugal fan‌: often used to eliminate noise and vibration during work and increase air volume and wind pressure.
‌Medium pressure centrifugal fan‌: Suitable for transporting gases with high dust content, high flue gas temperature or condensation water, etc.

what are centrifugal fans

Centrifugal fan application

‌Industrial Manufacturing‌: Centrifugal fans are used in many industrial environments, such as ‌steel metallurgy, ‌chemical industry, ‌mining, etc. In these industries, fans are usually used to strengthen air supply, exhaust, refrigeration and hot air systems. Especially in harsh environments such as high temperature, corrosion, dust, etc., centrifugal fans play an irreplaceable role.
‌‌Environmental protection equipment‌: Centrifugal fans are also widely used in environmental protection equipment, such as ‌sewage treatment, ‌exhaust gas purification, etc. At the same time, centrifugal fans also play an important role in dust removal equipment, incineration equipment and advanced physical noise reduction equipment.
‌Construction equipment‌: In the construction field, centrifugal fans are used in air conditioning, ventilation, hot air and other fields. Through the air supply and exhaust system, they realize the circulation and flow of air and promote the convection and ventilation of indoor air.
‌Temperature control‌: Centrifugal fans can change the ambient temperature by blowing air, so they have important uses in heating, ventilation, air conditioning, drying and other temperature regulation equipment.
‌Air purification‌: In special environments such as laboratories, operating rooms and other places that have strict requirements on air quality, centrifugal fans can be used for air filtration and purification.
‌Agricultural cultivation‌: In agricultural production, centrifugal fans are used to provide a stable air environment for greenhouse plant growth, animal feeding, etc.
‌Transportation equipment‌: In transportation equipment such as trains and ships, centrifugal fans are also used for air circulation.
‌‌Food Processing‌: In the food processing industry, centrifugal fans are also very commonly used, such as drying equipment, cooling equipment and other food processing technology equipment.

9 10 月 2024

centrifugal fan type

Types of centrifugal fans‌ can be divided according to different classification standards. The following are several common classification methods and their corresponding types:
‌Classification by pressure and function‌:
Ventilator: The exhaust pressure is small, not exceeding 0.015MPa.
Blower: The exhaust pressure is slightly larger, not exceeding 0.2MPa.
Compressor: The exhaust pressure is relatively high, from 1MPa to over 100MPa.
‌Classification by working principle‌:
Centrifugal fan: After the airflow enters the impeller axially, it mainly flows in the radial direction, using centrifugal force.
Axial flow fan: The airflow enters the impeller axially and flows along the axis.
Rotary fan: uses the rotation of the rotor to change the volume of the air chamber.
‌Classification by impeller type‌:
Front-jet centrifugal fan: Gas enters vertically from the center of the impeller, with small air volume and low pressure.
Rear-jet centrifugal fan: There is a nozzle behind the impeller, which produces higher gas pressure and air volume.
Pull-type centrifugal fan: The impeller is reversed, suitable for processing high-concentration gases containing solid impurities.
Inclined flow centrifugal fan: The impeller axis forms an angle with the air inlet axis to improve efficiency.
Classification by characteristics‌:
Medium-pressure centrifugal fans: handle a certain amount of air, dust and other impurities, often used in air conditioning and ventilation systems.
Low-pressure centrifugal fan: air pressure below 50Pa, suitable for heating equipment.
High-pressure centrifugal fan: strong processing capacity, suitable for special industrial environments.
Axial flow centrifugal fan: handles low pressure and high flow conditions, suitable for large ventilation and air conditioning equipment.

centrifugal fan type

What is a centrifugal type fan?

Centrifugal fan is a machine that relies on input mechanical energy to increase gas pressure and discharge gas‌. It accelerates the gas through a high-speed rotating impeller, then decelerates and changes the flow direction, converting the kinetic energy into potential energy (pressure). Centrifugal fans are widely used in industrial and mining plants, civil buildings, large public buildings, power plants and other places as supporting equipment for air treatment facilities and hot air circulation facilities.
The structure of a centrifugal fan mainly includes casing, impeller, shaft, suction port, exhaust port and other components. The impeller is the main working component that generates wind pressure and transmits energy; the casing is used to introduce and discharge gas, and at the same time convert part of the kinetic energy of the gas into pressure energy; the impeller is installed and fixed on the crankshaft, and is connected to the motor through a coupling. The blade type of the impeller has a great influence on the performance of the ventilator. Backward-facing blades have higher efficiency but lower gas flow rate, forward-facing blades have higher gas flow rate but lower efficiency, and radial blades have characteristics between the two. between.
The working principle of centrifugal fans is based on the principle of converting kinetic energy into potential energy. The gas enters the impeller from the axial direction, is accelerated by the impeller, and then leaves the impeller along the radial direction to do work by the centrifugal force generated. The gas accelerates in the impeller, then decelerates in the diffuser, changes the flow direction, and converts kinetic energy into pressure energy. In a single-stage centrifugal fan, the gas enters the impeller from the axial direction, flows through the impeller and then enters the diffuser. In a multi-stage centrifugal fan, the airflow enters the next impeller through the refluxer, generating higher pressure.

Centrifugal fan working principle

‌The working principle of a centrifugal fan is to use a high-speed rotating impeller to accelerate the gas, and then convert the kinetic energy into potential energy (pressure) by decelerating and changing the flow direction.
The centrifugal fan is mainly composed of air inlet, impeller, deflector, casing and motor. When working, the motor drives the impeller to rotate at high speed, and the gas from the air inlet is sucked into the impeller. After the impeller accelerates the gas, it is discharged through the deflector and casing. The working principle of the centrifugal fan is based on the action of centrifugal force. When the impeller rotates at high speed, the gas is accelerated to the action of centrifugal force, thus generating a pressure difference. The pressure of the gas at the air inlet is low, while the pressure of the gas at the air outlet is high. Therefore, the gas will flow from the air inlet to the air outlet along the pressure gradient.

Centrifugal fan function

Centrifugal fans are driven fluid machines that are widely used in ventilation, dust removal and cooling of factories, mines, tunnels, cooling towers, vehicles, ships and buildings; ventilation and induced draft of boilers and industrial furnaces; ‌Cooling and ventilation in air conditioning equipment and ‌household appliances; drying and sorting of grains; ‌wind tunnel wind sources and ‌inflation and propulsion of hovercrafts, etc.
Its working principle is to use a high-speed rotating impeller to accelerate the gas, then decelerate it, change the flow direction, and convert the kinetic energy into potential energy (pressure). In a single-stage centrifugal fan, the gas enters the impeller from the axial direction, changes to the radial direction when the gas flows through the impeller, and then enters the diffuser. In the diffuser, the gas changes its flow direction and the cross-sectional area of the pipe increases to decelerate the gas flow. This deceleration converts kinetic energy into pressure energy. The pressure increase mainly occurs in the impeller and secondarily during the pressure expansion process. In multi-stage centrifugal fans, a reflux is used to direct the airflow into the next impeller, creating higher pressure.

Centrifugal fan application

‌Industrial Manufacturing‌: Centrifugal fans are used in many industrial environments, such as ‌steel metallurgy, ‌chemical industry, ‌mining, etc. In these industries, fans are usually used to strengthen air supply, exhaust, refrigeration and hot air systems. Especially in harsh environments such as high temperature, corrosion, dust, etc., centrifugal fans play an irreplaceable role.
Environmental protection equipment‌: Centrifugal fans are also widely used in environmental protection equipment, such as ‌sewage treatment, ‌exhaust gas purification, etc. At the same time, centrifugal fans also play an important role in dust removal equipment, incineration equipment and advanced physical noise reduction equipment.
‌Construction equipment‌: In the construction field, centrifugal fans are used in air conditioning, ventilation, hot air and other fields. Through the air supply and exhaust system, they realize the circulation and flow of air and promote the convection and ventilation of indoor air.
‌Temperature control‌: Centrifugal fans can change the ambient temperature by blowing air, so they have important uses in heating, ventilation, air conditioning, drying and other temperature regulation equipment.
‌Air purification‌: In special environments such as laboratories, operating rooms and other places that have strict requirements on air quality, centrifugal fans can be used for air filtration and purification.
‌Agricultural cultivation‌: In agricultural production, centrifugal fans are used to provide a stable air environment for greenhouse plant growth, animal feeding, etc.
‌Transportation equipment‌: In transportation equipment such as trains and ships, centrifugal fans are also used for air circulation.
Food Processing‌: In the food processing industry, centrifugal fans are also very commonly used, such as drying equipment, cooling equipment and other food processing technology equipment.

9 10 月 2024

centrifugal fan rotation direction

Centrifugal fan rotation direction

The rotation direction of the centrifugal fan can be determined by observing the rotation direction of the impeller.
‌Looking at the direction of rotation of the impeller from the spindle pulley motor side, clockwise rotation is right-hand rotation, and counterclockwise rotation is left-hand rotation‌.
The left-hand and right-hand rotation of the centrifugal fan refers to the direction of rotation of the wind wheel. Along the direction of rotation of the wind wheel, the gas movement toward the inside of the casing is a right-hand centrifugal fan, and vice versa is a left-hand centrifugal fan.
Facing the direction of the air outlet, the one with the air inlet on the left is left-handed, and the one with the air inlet on the right is right-handed.
These methods can help determine the direction of rotation of the centrifugal fan and ensure its normal operation.

Fan discharge orientation

‌‌How to determine the direction of fan air outlet
‌Judge by the skeleton and wiring direction‌: Generally, the side where the skeleton can be seen is the air outlet side, and the side where the skeleton cannot be seen is the air inlet side; the side where the wiring can be intuitively seen is the air inlet side, and the side where the wiring cannot be seen is the air inlet side. The side of the line is the wind outlet side.
‌Judge by blade shape‌: The side with a more rounded shape of the blade is the air inlet side, and the unrounded side is the wind outlet side.
‌Judge by the direction of blade rotation‌: clockwise rotation indicates air outflow, counterclockwise rotation indicates air inflow.
‌Judge by the fan mark‌: The side with the mark is the air outlet side, and the side without the label is the air inlet side.
‌Judging by the installation direction of the exhaust fan‌: the air outlet side of the exhaust fan should be facing outside, and the air inlet side should be facing indoors.
‌Judge by the installation position of the chassis fan: the front of the chassis fan is the air inlet and the back is the air outlet.

What is the direction of the centrifugal fan flow?

The airflow direction of the centrifugal fan is axially entering the impeller, and then flowing radially through the rotation of the impeller. ‌ When the centrifugal fan is working, the airflow enters the impeller from the axial direction. As the impeller rotates, the airflow increases its energy under the action of inertia and leaves the impeller along the radial direction.
The specific process of the airflow direction of the centrifugal fan is as follows: the airflow first enters the impeller axially, and then rotates driven by the impeller, and uses the centrifugal force generated to discharge the airflow in the radial direction. This process allows the air flow to gain energy, thereby achieving gas transportation and compression.
The airflow direction of a centrifugal fan is closely related to its working principle. The centrifugal fan generates centrifugal force through the rotation of the impeller, sucking the airflow from the axial direction, accelerating the airflow through rotation, and then discharges it in the radial direction. This design allows centrifugal fans to efficiently transport and compress gas‌.

Centrifugal fan rotation direction diagram

9 10 月 2024

pneumatic conveying of solids

Pneumatic conveying of solids

Solids conveying is a chemical unit operation that is important in chemical production. In chemical production, many kinds of raw materials, semi-finished products and finished products are in a solid state and need to be transported from one place to another.
The transportation of solid materials must ensure efficiency and maintain the quality of the materials. In the solid conveying area, under the action of the rotating screw, the solid polymer material added from the hopper is transported and compacted forward through the friction between the inner wall of the barrel and the surface of the screw.
In the solid conveying area, due to the lower temperature, the material still remains in a solid state and is gradually solidified.
At the same time, the gas mixed in the loose material is eliminated.

pneumatic conveying of solids

Pneumatic conveyor working principle

The working principle of the pneumatic conveyor is to use the energy of air flow to transport granular materials in the direction of air flow in a closed pipe. ‌
This process is a specific application of fluidization technology, which uses pressurized air as the transport medium to transport materials from one place to another.
‌Basic Principle‌: Pneumatic conveyors use the energy of air flow to transport granular materials from one place to another through closed pipes.
This conveying method can be carried out in horizontal, vertical or inclined directions, and during the conveying process, physical operations such as heating, cooling, drying and air flow classification of materials or certain chemical operations can be performed simultaneously.
‌System composition‌: Pneumatic conveying system usually consists of feeder, conveying pipeline, separator and ‌material warehouse.
The feeder is responsible for feeding materials into the conveying pipeline, which is the main channel for material transmission.
The separator is used to separate the transported gas and materials, and the material warehouse is the storage location of the materials.

pneumatic conveying of solids

Dilute phase pneumatic conveying system calculation

‌The calculation of dilute phase pneumatic conveying system mainly involves the determination of parameters such as gas flow rate, pipe diameter, conveying speed and pressure drop. ‌
Gas flow calculation
‌Definition‌: Gas flow refers to the flow of gas through the pipeline system, in cubic meters/hour.
‌Key parameters‌: Q (gas flow rate), A (cross-sectional area), V (gas flow rate), Y (transport rate).
‌Explanation‌: The calculation of gas flow rate is the basis for the design of dilute-phase pneumatic conveying system and directly affects the conveying efficiency and cost‌.
Pipe diameter calculation
‌Definition‌: Pipe diameter refers to the inner diameter of the delivery pipe, in millimeters.
‌Key parameters‌: D (pipe diameter), Q (gas flow rate), V (gas flow rate).
‌Note‌: The selection of pipe diameter requires comprehensive consideration of gas flow, transportation distance and speed, as well as cost factors‌.
Conveying speed calculation
‌Definition‌: Conveying speed refers to the average speed of materials in dilute phase pneumatic conveying, in meters per second.
‌Key parameters‌: V (conveying speed), Q (gas flow rate), A (cross-sectional area), Y (conveying rate), ρ (material density).
‌Note‌: The calculation of the conveying speed needs to consider the physical properties of the material and the gas flow rate, which has an important impact on the conveying efficiency and stability.
Pressure drop calculation
‌Definition‌: Pressure drop refers to the pressure drop caused by frictional resistance, pipeline bending and other factors in the gas transportation pipeline.
‌Key parameters‌: ΔP (pressure drop), f (friction coefficient), L (pipe length), D (pipe diameter), Q (gas flow rate), A (cross-sectional area).
‌Note‌: The calculation of pressure drop is crucial for evaluating the energy consumption and efficiency of the conveying system, and the comprehensive impact of multiple factors needs to be considered‌.

pneumatic conveying of solids

What are the different modes of pneumatic conveying?

‌There are four main modes of pneumatic conveying: suction type, pressure type, mixed type and flow type. ‌
‌Suction pneumatic conveying‌: This mode uses air flow with a pressure lower than atmospheric pressure to convey materials. Its advantages include a simple feeder, the ability to convey from multiple places to one place, and the ability to convey from low and narrow places. However, the conveying distance and conveying volume of suction pneumatic conveying are limited, the sealing performance is required to be high, and the conveyed air needs to be processed before it can enter the fan and be exhausted.
‌Pressure-feed pneumatic conveying‌: Contrary to suction conveying, pressure-feed pneumatic conveying uses air flow with a pressure higher than atmospheric pressure to transport materials. Its main advantages include the ability to transport from one place to multiple places, long transport distance, high height, large transport capacity and high efficiency. However, pressure-feed pneumatic conveying consumes a lot of power, has high sealing requirements, and has a complex feeder structure.
‌Hybrid pneumatic conveying‌: This mode combines the characteristics of suction and pressure conveying. It can not only suck materials from multiple places, but also transport materials to multiple places, and the conveying distance is long. However, the hybrid pneumatic conveying device is more complex, and the passage of material-containing gas through the fan will accelerate the wear of the fan.
‌Flow pneumatic conveying‌: This is a modified form of pneumatic conveying. The material exhibits fluid-like properties during the conveying process. Its advantages include good maneuverability, high speed and stability, good continuity, and efficient containerization. Streaming pneumatic conveying is suitable for conveying large quantities of materials.

8 10 月 2024