working principle of natural gas compressor maintenance and repair of natural gas compressor  

Working principle of natural gas compressor

When the compressor is running, the motor drives the crankshaft to rotate, and the piston moves back and forth through the connecting rod. When the crankshaft rotates for one cycle, the piston moves back and forth once, and the process of suction, compression and exhaust is realized successively in the cylinder, that is, a working cycle is completed.

(1) During the suction process, when the piston moves to the left, the working volume in the cylinder gradually increases and the pressure gradually decreases. When the pressure drops slightly below the pressure in the intake pipe, the gas in the intake pipe will push open the suction valve and enter the cylinder until the piston reaches the leftmost position (also known as the inner dead center), the working volume is the maximum and the suction valve begins to close.

(2) During compression, when the piston moves to the right, the working volume in the cylinder decreases and the gas pressure increases gradually. Because the suction valve has a check function, the gas in the cylinder cannot flow back to the intake pipe. At the same time, because the gas pressure in the exhaust pipe is higher than that in the cylinder, the gas in the cylinder cannot flow out of the exhaust valve, and the gas in the exhaust pipe cannot enter the cylinder due to the check effect of the exhaust valve. At this time, the amount of gas in the cylinder remains constant, and the gas pressure increases with the right movement of the piston.

(3) During the exhaust process, when the piston moves to a certain position to the right, the gas pressure in the cylinder rises to slightly higher than the gas pressure in the exhaust pipe, and the gas will push open the exhaust valve and enter the exhaust pipe until the piston moves to the rightmost position (also known as the outer dead center). When the exhaust valve is closed, the piston moves left again, and the above process repeats.

Difference between natural gas compressor and ordinary compressor

Natural gas compressor is different from ordinary compressor. Natural gas compressor mainly compresses natural gas (including content, methane, propane, etc.) with high pressure and high risk level. Ordinary compressor mainly compresses air, which is very single to medium and low pressure.

Compressed natural gas has the same composition as pipeline natural gas, The main component is methane (CH4). CNG can be used as vehicle fuel. LNG (liquefied natural gas) can be used to make CNG. This CNG fueled vehicle is called NGV (natural gas vehicle). Liquefied petroleum gas (LPG) is often confused with LNG. In fact, they are obviously different. The main component of LPG is propane (more than 95%), there is also a small amount of butane. LPG is stored in liquid tank container under appropriate pressure and is used as civil fuel and vehicle fuel.

Maintenance of natural gas compressor

In order to reduce the damage of compressor parts and prolong the service life of the compressor, daily maintenance and repair is very key and necessary. Daily maintenance mainly includes: regular lubrication and oil change of the equipment, anti-corrosion of the equipment, regular calibration of the accuracy of the equipment, etc., so as to minimize the wear and failure of parts and keep the equipment in normal working state as far as possible. The specific maintenance process is generally divided into quarterly maintenance, semi annual maintenance and annual maintenance.

Quarterly maintenance

(1) The venting system shall be cleaned and inspected every quarter to observe the sensitivity of solenoid valve action. The cleaner the venting system is cleaned, the more sensitive the solenoid valve action will be.

(2) Clean the copper based sintered filter in front of the solenoid valve to make it clean and free of dirt as far as possible.

(3) For the filter element of the filter, consider whether to replace it according to the specific service conditions and environmental factors.

(4) Air valves at all levels shall also be thoroughly and carefully cleaned to remove carbon deposits as far as possible.

(5) Clean the outside of the air compressor to ensure that it is clean and free of dirt; Change the compressor oil according to the specific situation.

(6) After cleaning, the moving structure of the compressor shall be calibrated and checked. For example, check the tightness of the V-belt, the lubrication of the main motor, and adjust the clearance between various components to ensure the flexibility of its working process.

(7) Pay attention to the comprehensive blowdown of separator, emptying gas collector, filter, recovery tank, etc.

2. Semi annual maintenance

(1) Check whether the pressure gauge is qualified and whether the action value of the pressure controller is within the specified range.

(2) Check whether all moving mechanisms of the compressor operate normally and whether the action value is flexible.

(3) Check the performance of the safety valve of the air storage tank to ensure that it can be opened in time within the safe use range at the maximum pressure.

(4) Carefully clean the outside of the compressor and the inner cavity of the air storage tank, and check whether the compressor and suction filter are clean and need to be replaced.

(5) Carefully check the pipe to prevent air leakage.

(6) Test the motor and electrical appliances to ensure their normal operation.

3 annual maintenance

(1) Send the compressor to the unit designated by the Labor Bureau for testing and checking the safety valve.

(2) Check the cooling fan, check valve, etc.

(3) Replace the coolant.

(4) Comprehensively inspect the hydraulic cylinder or stepping motor, stepping limit device, etc.

Principles for maintenance of natural gas piston compressor  

To maintain and maintain the natural gas compressor, we should master certain methods and abide by certain principles and requirements. If we can't do it, we can't achieve the purpose of prolonging the mechanical life. The compressor shall be maintained regularly. The importance of maintenance cannot be realized until the compressor is worn to a certain extent.

Keep in mind that "pay equal attention to maintenance and repair and focus on prevention". The maintenance and repair of the compressor is a long-term work. We should deeply understand the truth that quantitative change reaches qualitative change. Only regular maintenance can prolong the service life of the machine. At the same time, we should correctly deal with the relationship between "maintenance" and "repair", "maintenance" and "use". It is futile to only repair without maintenance or only use without maintenance.

In the process of maintenance, pay attention to step by step to ensure the quality. Check item by item, and do not miss inspection or maintenance. Pay attention to record in time during maintenance, and report problems to relevant departments in time.

During operation, pay attention not to exceed the load of the compressor to eliminate potential safety hazards. At the same time, pay attention to the accuracy of the calibration equipment in the maintenance process to ensure its flexibility; Test the safety and reliability of equipment to prevent dangerous accidents.