Basic knowledge of air compressor

Basic knowledge of air compressor

Classification of air compressors:

　　 Air compressors are divided into:

　　1, speed type;

　　2, volumetric type; volumetric type is divided into rotary and reciprocating;

　　 Rotary type: (1) Rotor type air compressor; (2) Screw type air compressor; (3) Sliding vane type air compressor.

　　 Reciprocating type: (1) Piston type; (2) Membrane type.

　　 Air compressors can be divided into two categories: speed type and volume type according to the working principle.

　　 Velocity type: Relying on the action of the gas in the high-speed rotating impeller to obtain greater kinetic energy, and then sharply reduce the speed in the diffuser to convert the kinetic energy of the gas into potential energy, thereby increasing the gas pressure. There are two basic types of speed type: centrifugal type and axial flow type.

　　 Volumetric type: The purpose of increasing gas pressure is achieved by directly compressing the gas to reduce the volume of the gas. The volumetric type is divided into rotary and reciprocating according to the characteristics of the cylinder to measure the piston. Most of the air compressors equipped in the oxygen chamber adopt positive displacement.

　　 Rotary type: The piston rotates, the piston is also called dry, the number of rotors is different, and the shape of the cylinder is different. Rotary type includes rotor type, screw type, sliding vane type and so on.

　　 Reciprocating type: The piston reciprocates and the cylinder is cylindrical. The reciprocating type includes piston type and membrane type. The piston type is currently the most widely used type. Most of the air compressors used in the oxygen chamber adopt piston type. The classification, model representation, structural features and working principle of piston air compressors are introduced as follows:

　　 Piston-type air compressors are generally classified by discharge pressure, displacement (volume flow), structure type and structural characteristics.

1. According to the level of exhaust pressure:

　　 low pressure air compressor, discharge pressure≤1.0MPa

　　 Medium pressure air compressor 1.0MPa＜discharge pressure ≤10MPa

　　 high pressure air compressor 10MPa＜discharge pressure ≤100MPa

2. The size of the connected displacement is divided into:

　　Small air compressor 1m3/min＜discharge volume≤10m3/min

　　 Medium-sized air compressor 10m3/min＜discharge volume≤100m3/min

　　 Large air compressor, displacement＞100m3/min

　　The displacement of the air compressor refers to the free gas flow in the suction state.

　　General regulations: The shaft power is less than 15KW, and the discharge pressure is less than or equal to 1.4MPa, which is a miniature air compressor.

　　3. According to the relative position of the cylinder center line and the ground, it is divided into:

　　 vertical air compressor-the cylinder center line is arranged perpendicular to the ground.

　　 Angle type air compressor-the cylinder center line is at a certain angle with the ground (V type, W type, L type, etc.).

　　 Horizontal air compressor-the cylinder center line is parallel to the ground, and the cylinder is arranged on the side of the crankshaft.

　　 Pair of dynamic balanced air compressors-the cylinder center line is parallel to the ground, and the cylinders are symmetrically arranged on both sides of the crankshaft.

　　4 is divided into:

　　Single acting-the gas is compressed only on one side of the piston.

　　Double acting-gas is compressed on both sides of the piston.

　　 water-cooled-refers to the cylinder with a cooling water jacket, and water cooling.

　　 Air-cooled type-the outer surface of the cylinder is cast with fins and air-cooled.

　　Fixed type-the air compressor unit is fixed on the foundation.

　　Mobile-The air compressor unit is placed on a mobile device for easy transportation.

　　With oil lubrication-refers to the oil injection lubrication in the cylinder and the circulating lubrication of the motion mechanism.

　　 No oil lubrication-means that the cylinder is not lubricated with oil, the piston and cylinder are running dry, but the transmission mechanism is lubricated by the lubricating oil.

　　 All oil-free lubrication-the transmission mechanism in the cylinder is oil-free.

　　 is also divided into crosshead (medium and small oil-free air compressor), no crosshead (V, W type low pressure micro air compressor); single-stage compression, two-stage or multi-stage compression