- laws of technical thermodynamics
- piston compressors, screw and rotary vane
- knowledge of the principle of piston machines actions
- knowledge of the technical requirements for the systems of compressed air pnevmomehanizmov
- pipe, pressure switchair
- compliance and safety regulations
Many industrial equipment works with the use of compressed air produced by different types of compressors.When staffing arrangements for the production of various compressed air systems require to know how the compressor works.To select the equipment when creating a workflow by using compressed air, it is necessary to know how the compressor, which can meet the specified requirements.Principle of the compressor is based on the technical laws of thermodynamics.Used basic thermodynamic parameters of the gas: pressure, temperature and specific gravity or density.Regularities of thermal processes in the compressor are considered on a simplified model of the ideal compressor.There are three w
most widely reciprocating compressors.They are reliable and easy to use, compact, have stable performance.Due to the wide technical capabilities and versatility, reciprocating compressors meet the requirements of various fields of economic activity.They air volume ranges from movement of the piston from the top dead center to bottom dead center.Differential pressure is created inside the cylinder has a suction valve automatically opens and air enters the cylinder.When the piston moves in the opposite direction, the air is compressed and the pressure rises in the cylinder.The suction valve is closed, the discharge - opens.Compressed air flows from the cylinder into the pipeline or receiver.Structurally, the compressor includes: a piston, cylinder, engine, drive shaft, intake and discharge valves, filter and receiver.
During operation of the compressor motor rotates the crank-crank or eccentric drive shaft.By converting the rotary motion of the shaft into a reciprocating motion of the piston, there is a cavity filled with air receiver.Using a special filter air entering the compressor is cleaned and dried.Admission to the air compressor cylinder with simultaneous operation of the valves.In the receiver the compressed air is stored and then transmitted by pipeline actuators.Receiver reduces fluctuations in the compressed air in the system and creates the necessary amount for continuous operation of the actuators.This achieves reliable operation of the entire air system.Used piston compressors of simple and double action.
To ensure efficient and safe operation, compressed air systems equipped with optional automatic operation of control systems.Air pressure switch controls the compressor capacity when changing the amount of consumable compressed air.Automation provides the compressor when the pressure in the receiver on and off - when the maximum allowable.Such a system reduces wear on the pistons and extends the life of the compressor.Depending on the generated pressure piston compressors are divided into types: low pressure - up to 1.2, the average - 10, high - 100, super high - more than 100 MPa.According to the number of steps they are divided into single-stage, two-stage and multi-stage.
operating principle of the screw compressor is based on the rotation of the two rotors mounted in the housing.The rotor is designed as a special screw thread profile.Air is sucked in portions with consistent movement of the spiral cutting troughs when the rotor rotates.In contrast, a reciprocating compressor is compressing air continuously.To ensure the normal functioning of the screw rotor profile must have a continuous line of contact.On the rotor rotary vane compressors are made with grooves installed in them plates.When the rotor air is compressed in the cells between the working plates.The volume of the working cavities in the rotor during rotation is reduced by providing air between the compression plates and the compressor stator.The compressed air is cleaned in the oil separator, is then fed in via the air collector and the locking apparatus to consumers.
When choosing a compressor is necessary to conduct an assessment of its quality to meet the requirements of compressed air production.Piston compressors have the following drawbacks: the relatively limited productivity;It requires a thorough purification of air;a relatively high level of noise and vibration;increased frequency of maintenance and repair.The use of piston compressors for air systems efficiently with small and medium pressure and flow.For enterprises with large pressures and the needs of the compressed air is expedient to use screw compressors.Their advantages: high performance in continuous operation, which increases the efficiency of the compressor;great durability of operation;low noise during operation;little need for maintenance and repair.The disadvantages are the high cost compared to reciprocating compressors.