What are the reasons for incomplete degreasing and oil removal of sanitary-grade stainless steel

The incomplete degreasing and oil removal of sanitary-grade stainless steel welded pipes may be caused by the following reasons: 

Improper selection of degreasing agent

Insufficient degreasing ability: Different types of oil stains require different types of degreasing agents to remove. If the selected degreasing agent has insufficient ability to dissolve and emulsify the oil stains on the surface of stainless steel welded pipes, it will be difficult to completely remove the oil stains. For example, for oil stains containing a large amount of grease, if a water-based degreasing agent is used, it may not be able to effectively dissolve the grease, resulting in incomplete degreasing. 

Incompatibility with pipe surface: Some degreasers may undergo chemical reactions with the surface of stainless steel, forming a protective film that hinders the contact between the degreasers and the oil stains, thereby affecting the degreasing effect. Or the degreasers may not be able to properly wet the pipe surface, failing to fully cover the oil stains, resulting in some oil stains not being treated. 

The parameters of the degreasing process are unreasonable.

Too low temperature: Temperature has a significant impact on the degreasing effect. Generally speaking, appropriately increasing the temperature can accelerate the reaction speed of the degreasing agent and the dissolution speed of the oil stains. If the temperature during the degreasing process is too low, the activity of the degreasing agent decreases, and the oil stains are difficult to be removed quickly, thus resulting in incomplete degreasing. 

Insufficient time: Degreasing requires a certain amount of time for the degreasing agent to fully react with the oil stains. If the degreasing time is too short, the degreasing agent won't have enough time to completely dissolve or emulsify the oil stains and separate them from the surface of the pipe, resulting in incomplete degreasing. 

Insufficient concentration: The concentration of the degreasing agent directly affects its degreasing ability. When the concentration is too low, the effective components in the degreasing agent have a low content, unable to provide sufficient force to remove oil stains, resulting in poor degreasing effect. 

Improper surface treatment of the pipe material

There are impurities on the surface: If there are dust, metal shavings, etc. on the surface of the stainless steel welded pipe, these impurities will adhere to the oily surface, hindering the contact between the degreasing agent and the oil, making it difficult for the degreasing agent to function properly and resulting in incomplete degreasing. 

Oxide scale not removed: The oxide scale on the surface of the pipe material will affect the penetration and removal of the degreasing agent for oil stains. The presence of the oxide scale hides the oil stains in its crevices and pores, preventing the degreasing agent from effectively reaching the oil stains, thus resulting in incomplete degreasing. 

Insufficient cleaning process

Insufficient cleaning: After degreasing, the pipe materials need to be thoroughly cleaned with clean water to remove the remaining degreasing agent and oil stains on the surface. If the cleaning is not thorough, the remaining degreasing agent and oil stains will re-form an oil layer on the surface of the pipe materials, affecting the degreasing effect of the sanitary-grade stainless steel welding pipes. 

Water quality issue: The quality of the cleaning water also has an impact on the degreasing effect. If the water contains impurities, oil stains or has high hardness, it may form new dirt on the surface of the pipe material, or react with the degreasing agent, reducing the cleaning effect of the degreasing agent and resulting in incomplete degreasing.