1.Removal of oil contamination

(1).Degreasing with organic solvent
For precision parts (such as high-pressure oil pump, fuel injection nozzle, etc.), do not clean them with alkaline solution to avoid corrosion. Generally, it should be cleaned with gasoline, kerosene, diesel, alcohol and other organic solvents (not heated).

(2).Degreasing with alkaline solution
For the oil stain of iron and steel parts, alkaline solution can be added with a small amount of emulsifier, cleaned after heating, and then hot water can be used to clean the residual alkaline solution.

(3).Degreasing of aluminum alloy cleaning solution
Alkaline solution has strong corrosive effect on aluminum alloy, and the cost of organic solvent is expensive. Therefore, when cleaning aluminum alloy parts, sodium silicate or sodium carbonate can be added with a small amount of potassium dichromate and heated to 60 ~ 70 ℃ to form aluminum alloy cleaning solution. The cleaning effect is very good for multi crop thresher machine.

1.Removal of carbon deposits

(1).Mechanical removal
That is, use metal brushes, shovels, waste piston rings, etc. to scrape away the carbon deposits, but these things can not be used to remove the carbon deposits on precision parts, nor can they be erased with abrasive cloth, so as not to scratch the surface of parts. For precision parts, wooden, bamboo or copper scrapers are used to remove them.

(2).Chemical removal
Soak the parts in the prepared chemical solution to soften and fall off the carbon deposit, then take out the parts of groundnut sheller machine, wipe off the residual carbon deposit with a brush or old socks, and finally wash and wipe dry with hot water.

Preparation of chemical solution: 30 ~ 60g hydrochloric acid, 3 ~ 10g hexamethylenetetramine, 3 ~ 10g sodium dodecylbenzene sulfonate, 1g sodium dodecyl sulfate, 1 ~ 2G sodium chloride and 1 ~ 2G citric acid. Mix evenly. When the solution needs a large amount, add the amount according to the above proportion.

3.Scale removal

(1). Sodium hydroxide (caustic soda) removal
Remove the scale with silicate as the main component, add 2% ~ 3% sodium hydroxide (caustic soda) aqueous solution into the cooling system, release it after the standby vehicle runs for 1 ~ 2 days, clean it with clean water, then repeat it again, and finally thoroughly clean the cooling system with clean water.

(2).Hydrochloric acid removal
Remove the scale with carbonate and sulfate as the main components, use 8% ~ 10% hydrochloric acid and rhodine corrosion inhibitor solution equal to 3% of hydrochloric acid, heat it to 50 ~ 60 ℃, inject it into the water jacket, soak it for 2 ~ 3 hours and discharge it, then clean it with aqueous solution added with potassium dichromate, or inject 5% sodium hydroxide (caustic soda) solution into the water jacket to neutralize the residual acid solution. Then rinse with clean water for many times until it is clean.