The Advantages And Working Principle of Oil-free Compressors

The piston compressor is a commonly used type of compressor that compresses gas or air through a reciprocating piston.

What are the advantages of piston compressors?

What is the working principle of a nitrogen compressor?

How to Start and stop the compressor?

Advantages of piston compressors

1.High pressure and flow rate

A piston compressor can generate high pressure and large flow of gas, making it suitable for various applications, including industrial manufacturing, refrigeration, and air compression.

2.Efficiency

Piston compressors are usually more efficient than some other types of compressors (such as screw compressors) under partial load conditions because they can be adjusted as needed without wasting energy.

3.Maintainability

The construction of piston compressors is relatively simple and easy to maintain. Usually, maintenance personnel can easily replace pistons, seals, and other critical components to extend equipment life.

4.Wide applicability

Piston compressors are suitable for various gases and liquids, including nitrogen, oxygen, natural gas, etc., and are therefore widely used in various industrial and manufacturing fields.

Working principle of nitrogen compressor

Nitrogen compressors are mainly used in various industrial needs. They are connected by pipelines between the original inlet of the nitrogen compressor and the balance gas tank. When the sealing performance of the sealing box is not very good, the pipeline provides a certain pressure, preventing air from leaking into the cylinder from the gap between the sealing box and the piston rod, thereby ensuring the purity of compressed nitrogen.

When the compressor is running, the electric motor drives the crankshaft to rotate, and the piston moves back and forth through the connecting rod. The crankshaft rotates once, and the piston moves back and forth once. The cylinder sequentially completes the process of suction, compression, and exhaust, completing a working cycle.

(1) During the suction process, as the piston moves to the left, the working volume in the cylinder gradually increases while the pressure gradually decreases. When the pressure drops slightly below the pressure in the intake pipe, the gas in the intake pipe opens the suction valve and enters the cylinder until the piston reaches the left position (also known as the inner dead center). When the working volume is large, the suction valve begins to close.

(2) When the piston moves to the right during the compression process, the working volume in the cylinder decreases while the gas pressure gradually increases. Due to the check function of the intake valve, the gas in the cylinder cannot flow back into the intake pipe. At the same time, due to the gas pressure in the exhaust pipe being higher than the pressure inside the cylinder, the gas in the cylinder cannot flow out of the exhaust valve, and the gas in the exhaust pipe is blocked by the exhaust valve.

The air compressor provides preliminary compressed air to the nitrogen compressor, and then the nitrogen compressor separates the oxygen in the air through membrane separation and other devices, providing high pressure nitrogen.

Starting and stopping operations of the compressor

Compressor startup operation

1) Turn the car several times and check for any abnormalities. 2) Check whether each pipeline system meets the requirements of the process flow. 3) Open the water supply and return valves on the cooling water circuit and check the water supply situation. 4) Fully open the air valve and intake valve, and fully close the test intake and exhaust valves. 5) Start the auxiliary oil pump and adjust the oil supply pressure to 0.15~0.3MPa. 6) Start the main motor, wait for oxygen to fill the unit, fully open the exhaust valve, and at the same time, fully close the exhaust valve. 7) Adjust the oil pressure of the main oil pump to 0.2~0.3MPA

Compressor shutdown operation

1) Open the vent valve and close the discharge valve. 2) Press the stop button to stop the main motor. 3) Close the intake valve. 4) Cut off the power supply to the control circuit. 5) After the main engine stops running for 10 minutes, stop the auxiliary oil pump motor and then stop the water supply. 6) When parking in winter (temperature<5 ℃), the water in each level of cylinder and heat exchanger should be drained to avoid freezing and damaging the equipment. 7) If the parking time is too long, the compressor should be treated with rust prevention. Fill the test intake pipeline with dry nitrogen gas, slowly rotate the compressor to fill the gas path with nitrogen gas, then close the vent valve and the intake valve in the test pipeline. 8) During the parking period, manually turn the car 1-2 times a day, with a few turns each time.

Anqing Bailian Oil Free Compressor Co., LTD. has worked for several years to meet the need of customers. They can create a 24-hour engineering and development environment for oil free nitrogen compressor production.