Composition of blower

The blower is mainly composed of the following six parts: motor, air filter, blower body, air chamber, base (and oil tank), drip nozzle. The blower operates by the eccentric rotor in the cylinder, and makes the volume change between the blades in the rotor slot to suck in, compress and spit out the air. In operation, the pressure difference of the blower is used to automatically send the lubrication to the drip nozzle and drop into the cylinder to reduce friction and noise. At the same time, it can keep the gas in the cylinder from flowing back. This kind of blower is also called sliding vane blower.
By the dynamic action of the blades on the rotating impeller, the energy is transferred to the continuous flow of fluid or the energy from the fluid drives the blade to rotate, which is called the turbomachinery. In turbomachinery, the rotating blades do positive or negative work to the fluid, so that the pressure of the fluid increases or decreases. Turbomachinery is divided into two categories: one is the working machine, from which the fluid absorbs power to increase the head or head, such as vane pumps and fans; the other is the prime mover, in which the fluid expands, reduces pressure or water head to generate power, such as steam turbine and turbine. The prime mover is called turbine, and the working machine is called vane type fluid machinery.
According to the different working principles of the fan, it can be divided into two categories: the blade type and the volume type. The blade type can be divided into axial flow type, centrifugal type and mixed flow type. According to the level of pressure produced by the fan, it can be divided into blower, compressor and fan. China''s current machinery industry standard JB / t2977-92 stipulates: Fan refers to the fan whose inlet is standard air, and whose outlet pressure (gauge pressure) is less than 0.015MPa; the fan whose outlet pressure (gauge pressure) is between 0.015MPa and 0.2MPa is called blower; and the one whose outlet pressure (gauge pressure) is greater than 0.2MPa is called compressor.
The main components of the blower are: volute, collector and impeller.
The collector can guide the gas to the impeller, and the flow condition at the inlet of the impeller is guaranteed by the geometry of the collector. There are many kinds of collector shapes, mainly including cylinder, cone, cone, arc, arc, arc, etc.
The impeller is generally composed of four parts: wheel cover, wheel disc, blade and shaft disc. The connection mode of its structure is mainly welding and riveting. According to the different installation angle of impeller outlet, it can be divided into radial, forward and backward three kinds. Impeller is the most important part of centrifugal fan, driven by prime mover, is the heart of centrifugal turbomachinery. It is responsible for the energy transmission process described by Euler equation. The flow in centrifugal impeller is affected by impeller rotation and surface curvature, accompanied by flow separation, backflow and secondary flow, which makes the flow in impeller very complex. The internal flow condition of impeller directly affects the aerodynamic performance and efficiency of the whole stage and even the whole machine.
The volute is mainly used to collect the gas from the impeller. At the same time, the kinetic energy of the gas can be converted into the static pressure energy of the gas by moderately reducing the gas velocity, and the gas is guided to leave the volute outlet. As a fluid turbomachinery, it is a very effective method to improve the performance and work efficiency of the blower from the research of its internal flow field. In order to understand the real flow condition in centrifugal blower and improve the design of impeller and volute to improve the performance and efficiency, scholars have done a lot of basic theoretical analysis, experimental research and numerical simulation for centrifugal impeller and volute.
Other structure of blower:
Rotor: composed of shaft, impeller, bearing, synchronous gear, coupling, shaft sleeve, etc.
Bearing: 3000 type double row radial spherical roller bearing is selected as the locating end near the coupling end. As the free end, 32000 single row radial short cylindrical roller bearing is selected to adapt to the axial displacement of rotor during thermal expansion.
Synchronous gear: composed of gear ring and hub, easy to adjust impeller clearance.
Body: it is composed of casing and left and right wallboards. The left and right wallboards, bearing seats and sealing parts installed in the left and right wallboards can be used for each other.
Base: medium and small fans are equipped with common base, while large fans are only equipped with fan base, which is convenient for installation and debugging.
Lubrication: the gear is immersed and the bearing is splash lubricated. Good lubrication effect, safe and reliable.
Transmission mode: direct coupling is the main method. If required by performance specifications, V-belt pulley can also be used to change speed. Elastic coupling is selected for coupling, which can mitigate impact and compensate a small amount of axis deviation. In addition to the motor as the driving machine, the large flow fan can also use steam turbine or other driving machine.

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