How to deal with the air compressor after coking

Coking in air compressors is a complex problem caused by lubricating oil under the effects of high temperature, oxidation, metal catalysis, etc., and it needs to be dealt with in stages based on the causes. The following are specific treatment plans and prevention strategies:

1. In-depth analysis of the causes of coking

1. Lubricating oil deterioration
   • Mixing non-original oil products causes additive conflicts and reduces the oxidation temperature by 30-50℃.
   • If lubricating oil is used for extended periods of time (such as mineral oil exceeding 2000 hours), the acid value increases and accelerates coking.
2. Thermal management out of control
   • When the heat sink is blocked or the cooling scale thickness is greater than 1mm, the oil temperature may easily exceed the critical value of 95 ° C.
   • Frequent loading and unloading causes the oil temperature to fluctuate by ±15℃, accelerating the cracking of lubricating oil.
3. pollution intrusion
   • When the air filter element is damaged, the penetration rate of PM2.5 particles increases by 40%, directly polluting the oil circuit.
   • When the pH of cooling water of water-cooled models is less than 6, the catalytic coking rate of metal corrosion products is doubled.

2. Hierarchical treatment method

Mild coking (Characteristics: exhaust temperature> 90 ℃, sludge content <50 g)

1. online cleaning
   • joinOil path cleaner(The amount is 5% of the lubricating oil), run for 40 – 60 hours.
   • Used when changing oilhot oil flushing: Drain old oil within 5 minutes of shutdown to avoid hardening of deposits.
2. Handling of critical components
   • removingoil coreandoil filter, useAcetone soakUltrasonic cleaning after 12 hours.

Severe coking (Characteristics: stuck nose, bitumen>200g)

1. Disassemble and clean the whole machine
   • usecaustic soda solution(Concentration 8-10%) Heat to 60℃ and soak the handpiece for 24 hours.
   • coolerUse a high-pressure water gun (pressure>15MPa) to back-flush the copper tube.
2. system reconstruction
   • replacementAll-oil sealing ringAvoid corrosion by residual cleaning agents.
   • injectionof neolubeBefore, purge the line with nitrogen for 10 minutes.

3. Long-term prevention strategies

1. Oil management
   • establishOil sample testing archives, test acid value and viscosity every 500 hours.
   • Used when changing oilvacuum suction method, residual amount is <50ml.
2. intelligent monitoring
   • installationOil temperature sensor + dew point meter, Linkage control the start and stop of the cooling fan.
   • setPressure difference between loading and unloading ≥0.2MPaReduce temperature fluctuations.
3. environment adapting
   • Install in dusty environmentspre-filtering device(Filtration accuracy ≤1μm).
   • Water-cooled model matchingwater softener, hardness <60ppm.

typical cases: The air compressor of a ceramic factory was shut down for 72 hours due to coking. After testing, it was found that the air filter element was damaged (the filtration efficiency dropped from 99.9% to 82%). After replacing the genuine filter element and deeply cleaning the oil circuit, the operating temperature dropped by 18 ° C, and the annual coking amount was reduced by 85%. It is recommended to formulate an “Air Compressor Health File” to record the changing trends of key parameters and achieve preventive maintenance.