华东交通大学毕业设计
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黎春：螺杆压缩机的设计与运动仿真
中英文翻译
The screw air compressor
Screw air compressor is the injection of single stage double screw compressor, divided into single screw air compressor and screw air compressor, efficient use of belt drive, drive the host rotation of compressed air, through the oil for cooling the compressed air in the host, the host of air and oil discharge of the mixed gas after coarse, fine two channel separation, the compressed oil separated out in the air, finally get the clean compressed air. Cooler for cooling the compressed air and oil. With reliable performance, small vibration, low noise, convenient operation, few wearing parts, high efficiency is the biggest advantage of. Screw compressor is a new type compressor, air is compressed alveolar ridge volume change installed on the casing are mutually parallel rotor meshing and achieve. The rotor side in the case and it with precision internal rotation so that gas rotor slot between continuously cyclical changes in volume and along the rotor axis, by the suction side to the discharge side suction, compression, exhaust, complete three working process.
Twin screw compressor is a double volume type rotary compressor, which is the main (Yang) side (Yin) with two rotor, composed of meshing pair, vice principal of rotor profile of external components of the element volume closed with the inner wall of the casing, shortage of twin screw is 40 cubic meters and above machine type to add gear, increase power consumption and prone to head lock; while the worm compressor is a uniaxial volume type rotary compressor, the meshing pair is composed of a worm wheel and two symmetrical layout, wall by the worm screw groove and the star wheel tooth surface and the casing form element volume closed, but the problem is the Star blade material has yet to be improved. The main performance parameters of screw type air compressor power, volume flow rate, pressure, exit temperature, discharge pressure and speed etc.. And in the design of screw air compressor, rotor of a pair of mutually meshing is a very important parameter. Because the performance of the compressor is closely related with the. The Yin and Yang of screw compressor rotor can be regarded as a pair of mutually meshed helical gear, therefore, the Yin and Yang of screw compressor rotor profile, but also to meet the meshing law. Rotor tooth surface and the vertical axis of the rotor section called rotor profile. The rotor profile of screw compressor is divided into symmetric and asymmetric line profile, and unilateral and bilateral type line profile, tooth top center line on both sides of the line are identical, called the symmetric line. On the contrary, the tooth top center line on both sides of the line is not at the same time, called asymmetric line. Only one side has a line in the internal or external rotor pitch circle, called single line. Pitch circle, are stylish lines, called bilateral profile. Generally speaking, the development and design of new line directly affect the performance of screw air compressor, design of screw air compressor performance also depends on the type of line. Screw compressor is constantly engaged on the rotor output compressed gas, therefore the spindle speed variation, volume flow rate, the exhaust pressure of the compressor will be affected, so the spindle speed is a major factor affecting the performance of screw compressor. When the exhaust pressure increases, compressor power consumption also increases, power increases, the decrease of economic benefit, so it has significant effect on energy consumption and exhaust pressure of the compressor. At the same time, some test results show that the
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华东交通大学毕业设计
external environment temperature will influence the performance of screw compressor. China in different seasons and different regions of the temperature difference, air temperature and ambient temperature of compressor is different, this parameter will directly affect the performance of screw compressor. Therefore, the factors that influence the performance of screw compressor were analyzed, will have the very big help to use screw compressor.
Screw compressor body is divided into two kinds, one kind is the belt transmission type, another kind is direct drive. Compressor belt transmission type which is suitable for 22KW power, is composed of 2 manufacturing according to the speed ratio of the belt pulley power via the belt transmission; direct drive type is the 1 coupling electric source and host together, worm compressor is directly driven by the worm rotation, while the double screw compressor is required add a gear in order to improve the speed of rotor.
The working process of Twin Screw Compressors: motor through a coupling, gear or belt driven by two main rotor, rotor meshing with each other, the main rotor is directly driven by the auxiliary rotor to rotate together, inhaled air in relatively under the action of negative pressure, the peak, and the tooth groove under the agreement, the gas is transported compression, when the rotor meshing surface to and the casing exhaust port, the compressed gas discharge.
The working process of screw compressor: motor with coupling or belt to power the worm shaft, driven by the worm gear worm star relative move in grooves, sealing element volume change, gas, transportation compression, when the design pressure, exhaust from the host shell triangle on the left and right symmetrical outlet to the oil and gas separator in the.
The host for the housing of screw compressor is provided with a spray hole, depending on the pressure difference, in the process of oil spray to the compression chamber to cool the gas, compressed, the sealing parts gap, and to vibration, noise and lubricating effect
Inhalation of dust in the air was blocking filter, in order to avoid premature wear and oil separator of compressor to be blocked, usually run 1000 hours or after a year, to replace the filter, dust, replace the time interval to shorten. Filter repair must stop, reduce stop time, recommended for the last new or cleaned standby filter. Clean filter steps are as follows:
The 1 to the two end surface of a plane turns tap filter, with most heavy and dry sand.
2 with less than 0.28MPa of dry air and air blowing along the opposite direction, the nozzle and the folded paper less distance of 25 mm, and along the length direction, bottom blowing. Grease 3 element, should be dissolved with no foam detergent in warm water wash, the warm water immersion for 15 minutes at least element, and use clean water hose with wash, do not use heating method to accelerate drying, a filter can be washed 5 times, and then discarded reusable.
The 4 filter is put in a check, such as thinning, pinhole or damaged should be abandoned. Cooler
The cooler tube, outer surface should pay special attention to the decision to keep clean, otherwise it will reduce the cooling effect, should be working conditions, regular cleaning. Gas tank / oil and gas separator
Gas tank / oil separator according to the pressure vessel manufacturing standards and acceptance, not arbitrarily modify. Safety valve
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黎春：螺杆压缩机的设计与运动仿真
Installed in the tank / oil and gas separator safety valve inspection at least once a year, adjust the safety valve should have professional and responsible, at least every three months to marathon a lever again, so that the valve opening and closing time, a safety valve to work properly.
Test steps are as follows:
1 close the gas supply valve; 2 connected to water; The 3 starting unit;
4 observe the working pressure, slowly clockwise pressure regulating bolt, when the pressure reaches the set value, the safety valve does not open or up to the specified value before the open, it must be adjusted. The adjustment procedure is as follows: 1 remove the cap and seal;
The 2 valve opening soon, loosen locknut and a positioning bolt half ring, valve open too late to loosen
The nut about a circle and release the positioning bolts half circle.
3 repeat detection step, the safety valve set pressure value, still can not open, again adjustment.
Motor overload relay
The relay normally open contact, must be closed, when the current exceeds the rated value, cut off the motor power supply.
The maintenance of screw compressor relative to the piston compressor is to lower the probability of a failure of many, but if use improper maintenance, the advantages of screw compressor is difficult to play. Many users began to use piston compressor screw air compressor, due to the maintenance of screw compressor does not understand, leading to frequent failure, causing the conflict between users and enterprises. So before using screw compressor to his use and maintenance instructions carefully read.
Installation place, on the machine's air ventilation, pressure station power supply cable and air switch specifications, water pressure and flow, exhaust pipe sizes have guidance. The instructions also principle and structure of the machine are described in detail, there are certain basic knowledge of mechanical and electrical personnel through carefully reading, can make correct judgement and treatment for common problems. There is a consumable part of screw compressor to the regular replacement of main lubricating oil, oil filter, air filter, oil filter, notable is replaced in the environment of different parts of the frequency also has the difference, so the screw compressor to daily use and inspection record. Transmission gear and belt drive
In the transmission system of the air compressor, generally can be divided into direct transmission and belt drive, long-term since, two kinds of transmission way merits has been one of the focus of the debate. Direct drive screw air compressor refers to the spindle motor through a coupling and a gear to drive the rotor, direct drive which in fact is not the real meaning of. Direct drive on real significance is directly connected to motor and rotor (coaxial) and the speed. This is obviously a little. So that the direct drive no energy consumption point of view is wrong.
Another way of drive for belt drive, the drive through the belt wheels of different diameters
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