Now commonly used air compression pumps are piston air compression pumps, screw air compression pumps, (screw air compression pumps are divided into twin-screw air compression pumps and single-screw air compression pumps), centrifugal compression pumps, and sliding vane air compression pumps, scroll air compression pumps. Below are definitions of the various compression pumps. Compression pumps such as cam, diaphragm and diffusion pumps are not included because they are special-purpose and relatively small in size.
Displacement compression pumps - compression pumps that rely directly on changing the volume of gas to increase gas pressure. Reciprocating compression pump - is a volumetric compression pump, the compression element is a piston, reciprocating motion in the cylinder.
Rotary compression pumps - are positive displacement compression pumps where compression is achieved by forced movement of a rotating element.
Sliding vane compression pump - is a rotary variable displacement compression pump, its axial sliding vane in the same cylindrical cylinder eccentric rotor for radial sliding. The air trapped between the slides is compressed and discharged.
Liquid-piston compression pump - is a rotary displacement compression pump, in which water or other liquids are used as pistons to compress the gas, and then the gas is discharged.
Roots Twin Rotor Compression Pumps - are rotary displacement compression pumps in which two Roots rotors engage with each other to trap the gas and send it from the inlet to the exhaust. There is no internal compression.
Screw Compression Pumps - are rotary displacement compression pumps in which two rotors with helical gears mesh with each other to compress and discharge the gas.
Velocity compression pumps - are rotary continuous-flow compression pumps in which a high-speed rotating vane accelerates the gas passing through it, thereby converting velocity energy into pressure. This conversion occurs partly in the rotating vanes and partly in the fixed diffuser or return baffle.
Centrifugal compression pumps - are velocity-type compression pumps in which one or more rotating impellers (the vanes are usually on the sides) accelerate the gas. The main gas flow is radial.
Axial-flow compression pumps - are velocity-type compression pumps in which the gas is accelerated by a rotor equipped with vanes. The main gas flow is axial.
Mixed-flow compression pumps - are also velocity-type compression pumps in which the shape of the rotor combines some of the characteristics of both centrifugal and axial flow.
Jet compression pumps - utilize a high-velocity gas or vapor jet stream to carry away intake gases, and then convert the velocity of the gas mixture into pressure at the diffuser.
Features of air compression pump:
The compression pump is driven directly by an electric motor, which produces a rotary motion of the crankshaft, which drives a connecting rod to produce a reciprocating motion of the piston, causing a change in the volume of the cylinder. Due to the change of pressure in the cylinder, through the inlet valve, the air through the air filter (muffler) into the cylinder, in the compression stroke, due to the reduction of cylinder volume, the compressed air through the role of the exhaust valve, through the exhaust pipe, the check valve (check valve) into the tank, when the exhaust pressure reaches the rated pressure of 0.7MPa by the pressure switch to control the automatic shutdown. When the pressure of the gas storage tank drops to 0.5-0.6MPa when the pressure switch is automatically connected to start.