Overhaul of the misunderstood air compressor host

Two Stage Screw Air CompressorPower Station Industry

Many air compressor users have such a wrong idea that as long as the air compressor can still be used, there is no need to overhaul it. But in fact overhaul is not only “first aid”, it is also necessary “health therapy” for every air compressor. Through the adjustment of the overhaul, the air compressor will be brought back to the right track to achieve efficient and stable operation.

1. Why does the main engine of the air compressor need to be overhauled?

As the air compressor equipment has been used for a certain number of years, various internal problems have begun to surface. Timely overhaul of the main engine and systematically solving internal safety hazards will effectively reduce the maintenance cost in the later period and ensure the good operation of the air compressor. Generally speaking, the following five major problems will appear after the air compressor works for a certain period of time:

1) The gap increases

The increase in the distance between the male and female rotors of the core components of the main engine will increase the leakage during the compression process and reduce the compression efficiency of the equipment. In addition, the expansion of the gap between the male and female rotors, the rear end cover and the bearing will mainly affect the sealing and compression efficiency of the compressor. At the same time, this will also have a great impact on the service life of the male and female rotors.

2) Increased wear and tear

Under normal circumstances, the operation of the machine will inevitably cause wear. Under normal circumstances, the wear will be reduced a lot due to the lubrication of the lubricating fluid. However, long-term high-speed operation will increase the degree of wear and cause wear and damage to other major components.

3) Part deformation

As the core compression component of the compressor, the internal components of the compressor host are exposed to high-temperature and high-pressure environments for a long time, coupled with high-speed operation, deformation will inevitably occur over time. At the same time, dust and impurities gradually accumulate in the machine. After a long period of operation, it may cause the deformation of the male and female rotors and increase the gap. In severe cases, the main engine may be stuck.

4) component damage

The vulnerable parts of the host part of the compressor mainly include: various gaskets, sealing rings, shaft oil seals, etc. Among them, the shaft oil seal has been in the environment of high temperature, high pressure and high speed operation for a long time, which greatly shortens its service life. Once damaged, it will cause oil leakage from the compressor. If it is not found in time, it is very likely that the male and female rotors and bearings will be burned due to lack of lubrication.

5) Increased cost

If the compressor has not been overhauled for a long time, a large amount of impurities caused by wear and tear will remain inside the equipment. Resulting in: a. shortening the service life of lubricating fluid; b. shortening the service life of oil filter element and air filter element; c. increasing friction, reducing compression efficiency and increasing electricity cost.

2. What will happen if the host is overdue?

If the running time of the main engine exceeds the overhaul period, the bearing wear and the matching clearance of the main engine will reach the limit value allowed by the technical conditions of the main engine. At this time, the main engine is in an extremely unsafe operating state, and the following serious consequences may occur at any time:

1) The operating load of the main engine increases, causing harm to the main motor and electrical system;

2) The exhaust volume of the air compressor will be greatly attenuated;

3) The most serious consequence is the sudden “locking” of the host.

3. How to judge whether the air compressor needs to be overhauled?

1) The host that has failed and “locked up”. Disassemble and disassemble inspection, comprehensively repair the performance of the mainframe after repair, repair cost, etc. to judge whether it has repair value.

2) still functioning host.

(1) Judgment based on the running time of the unit: Generally, the running time of the air compressor unit has reached 20,000 hours or the main engine must be overhauled after 4 years of operation.

(2) Judgment based on the actual unit operation detection analysis: through the corresponding data detection and analysis of unit operating parameters such as noise, operating current, operating temperature, exhaust volume, main engine vibration, etc., it is determined whether the main engine overhaul is required.

4. What are the work contents of the overhaul of the main engine of the air compressor?

1) Disassemble, pull out and press out the corresponding gears (or transmission devices such as pulleys) and bearings;

2) Clean the screw and shaft, adjust the gap, polish and repair the damaged surface of the shaft, screw and stator;

3) Press-fit the bearing, adjust the gap, and test each gap;

4) Trial run, run-in adjustment.

5. What problems should be paid attention to during overhaul?

1) Be careful during the disassembly process to avoid damage to the screw meshing surface and lock the thread;

2) Before installation, the unit should do a good job of cleaning all parts;

3) Replace the entire set of bearings with a special original brand.

6. What is the technical standard for air compressor overhaul?

1) Grinding the scratches on the rotor and the shell of the main engine head;

2) Calibrating the rotor, adjusting the gap; overhauling the oil circuit of the main engine, the precision of the gear, and the concentricity of the bearing;

3) The exhaust pressure does not drop by 5% compared with the new machine;

4) The actual exhaust volume under specified working conditions should not be less than 95% of the nominal exhaust volume;

5) The rotor should be subjected to a dynamic balance test, and its balance accuracy level should not be lower than G6.3;

6), the general vibration intensity should not be higher than 12mm/s (specifically depends on the specific model and the degree of rotor loss), and there is no obvious abnormal sound.


Timely overhaul of the air compressor will help to delay the overhaul of the air compressor and prolong its service life. At the same time, it also plays an important role in maintaining normal production and ensuring product quality, enabling enterprises to win market competition strong backing. It has a long service life, and at the same time, it also plays an important role in maintaining normal production and ensuring product quality, and has become a strong backing for enterprises to win market competition.

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