The material of the nozzle is stainless steel, and the sprayed liquid is a mixture of diesel oil and heavy oil. After working at high temperature (above 500°C) for a long time, the surface accumulates incompletely burned coke. The photo shows the surface of the stainless steel nozzle and the inside of the nozzle before cleaning. coke.

Put it in 100% C3b strong degreasing agent, soak overnight at room temperature, take it out and rinse it with clean water. It was found that the stainless steel heavy oil nozzle had been completely cleaned. To increase the cleaning efficiency and shorten the cleaning time, the agent can be heated or cleaned with ultrasonic vibration.

Samples before cleaning. After the stainless steel screw is headed, the surface is covered with tar, and the hexagonal inner hole is extruded to form high-temperature adhesion coke. The deeper the hexagonal inner hole, the harder it is to clean and remove the coke.

Dilute the powerful degreasing agent C3b into different concentrations such as 5%, 10%, 20%, 50%, 100%. At room temperature, place stainless steel screws and shake for 10 minutes (the simulated screw factory uses a drum to clean).

The picture below shows, from left to right, C3b diluted to 5%, 10%, 20%, 50%, and 100% for shaking and washing.

Shake for 10 minutes, remove and rinse.

For comparison, the figure below from left to right shows the results after shaking and washing with C3b diluted to 5%, 10%, 20%, 50%, and 100%.
From the cleaning results, it can be known that C3b can remove surface grease at a concentration of 5%~100%. However, the concentration of C3b above 20% can clean the coke attached to the surface, and the surface of the screw is relatively bright, and there is relatively no black coke attached.

From left to right, the figure below shows the results after shaking and washing with C3b diluted to 5%, 10%, 20%, 50%, and 100%.
It can be seen from the cleaning results that the carbon deposits in the English letter marks on the screw head are not completely removed when the C3b concentration is below 10%, and the carbon deposits in the English letter marks on the screw head are not completely removed.
In addition, the hexagonal inner hole is the extrusion point with the highest temperature, and the stainless steel here is darker due to oxidation. The brightness of stainless steel will not be restored by cleaning with C3b.

It can be seen from the results that after soaking in SOR04, the surface of stainless steel screws is brighter and the luster of stainless steel is restored. However, the screws cleaned with a concentration of C3b below 10% still have a small amount of carbon deposits on the surface.

Modify the formula of iron-containing steel oxide cleaner SOR04, improve its degreasing ability, and make SOR05.
Put oily stainless steel screws into 50% SOR05, shake and clean for 10 minutes. Remove and flush.

After cleaning the screws with SOR05, the grease on the surface has been cleaned. The stainless steel screws have also been brightened.
The picture on the right is before cleaning. The left side of the picture below is after cleaning with SOR05.

But from the point of view of the hexagonal inner hole, after cleaning with SOR05 alone, the color is still relatively dull compared with the process of cleaning with C3b first and then cleaning with SOR04.
From left to right, the picture below shows cleaning with SOR05 (10 tubes), cleaning with C3b diluted to 20%, 50%, and 100%, and soaking with SOR04 (3 tubes each). The screws cleaned with SOR05 still have a small amount of coke that has not been completely removed.