How is degreasing agent used in aviation manufacturing?

In the field of aviation manufacturing, degreasers are an important chemical treatment material, mainly used to remove grease, dirt and other contaminants from metal surfaces or other materials. Aviation manufacturing has extremely high requirements for the cleanliness of material surfaces, because any residual contaminants may affect the quality of subsequent processes and even endanger flight safety. Therefore, the application of degreasers in aviation manufacturing is of great significance. This article will elaborate on the types of degreasers, their mechanisms of action, their application scenarios, and precautions.

1. Types of degreasers

According to the different chemical composition and use, degreasers can be divided into the following categories:

1. Organic solvent degreaser: This type of degreaser is usually composed of organic solvents (such as acetone, ethanol, isopropanol, etc.), which can quickly dissolve grease and dirt. Its advantages are fast evaporation and good cleaning effect, but its disadvantages are flammable and explosive, and it has certain pollution to the environment.

2. Water-based degreaser: Water-based degreaser uses water as the main solvent, with added surfactants, alkali agents and other ingredients. Its advantages are environmental friendliness and high safety, but the cleaning effect may not be as good as that of organic solvent-based degreasers, and subsequent drying treatment is required.

3. Alkaline degreasers: These degreasers contain alkaline substances such as sodium hydroxide and sodium carbonate, which can decompose grease through saponification. They are suitable for treating heavy oil stains on metal surfaces, but may be corrosive to some non-metallic materials.

4. Acidic degreasing agent: Acidic degreasing agent usually contains ingredients such as phosphoric acid and sulfuric acid. It is mainly used to remove oxide layers and rust on the metal surface, and can also play a certain degreasing role.

5. Bio-enzyme degreaser: This type of degreaser uses the catalytic action of bio-enzymes to decompose grease. It is environmentally friendly and highly efficient, but it is more expensive and has certain requirements for temperature and environmental conditions.

2. Mechanism of action of degreasing agent

The mechanism of action of degreasing agent mainly includes the following aspects:

1. Dissolving action: Organic solvent degreasers dissolve grease and dirt, removing them from the surface of the material.

2. Emulsification: The surfactant in the water-based degreaser can emulsify the grease into tiny particles and disperse them in the water, making it easier to clean.

3. Saponification reaction: Alkaline degreasers react with oils and fats to produce water-soluble soaps and glycerin, thereby removing oils and fats.

4. Chemical reaction: Acidic degreasers remove oxide layers and rust from metal surfaces through chemical reactions, and can also decompose some grease.

5. Biodegradation: Bio-enzyme degreasers decompose grease into small molecules through the catalytic action of enzymes, making them easier to clean.

3. Application scenarios of degreasing agents in aviation manufacturing

1. Pretreatment of metal parts: In aviation manufacturing, metal parts (such as aluminum alloy, titanium alloy, stainless steel, etc.) must be degreased before processing, welding or painting. Degreasing agents can effectively remove pollutants such as cutting oil and anti-rust oil on the metal surface to ensure the quality of subsequent processes.

2. Composite material surface treatment: Composite materials (such as carbon fiber reinforced composite materials) are widely used in aviation manufacturing. These materials also need to be degreased before bonding or painting. Since composite materials are highly sensitive to chemicals, mild water-based or bio-enzyme degreasing agents are usually used.

3. Cleaning of engine parts: Aircraft engine parts are easily contaminated with grease and dirt during the manufacturing and maintenance process. Degreasers can thoroughly clean these parts to ensure their performance and safety.

4. Surface preparation before painting: Before painting an aircraft, the surface must be thoroughly cleaned to remove grease, dust and other contaminants. Degreasers play a key role in this process, improving the adhesion and durability of the coating.

5. Repair and maintenance: During the repair and maintenance of aircraft, degreasers are used to clean parts and equipment to ensure their normal operation and extend their service life.

4. Precautions for using degreasing agent

1. Choose the right degreaser: Choose the right degreaser based on the material type and the nature of the contaminants. For example, organic solvent degreasers are suitable for metal parts, while water-based degreasers are more suitable for scenarios with higher environmental requirements.

2. Control the use conditions: The effect of the degreasing agent is affected by factors such as temperature, concentration and time. During use, these parameters should be strictly controlled according to the process requirements to ensure the effect.

3. Pay attention to safety protection: Degreasing agents are usually corrosive or toxic. Operators should wear protective gloves, goggles and other equipment to avoid direct contact with skin and eyes.

4. Environmental protection treatment: The used degreaser may contain harmful substances and should be recycled and treated in accordance with environmental protection requirements to avoid pollution to the environment.

5. Regular inspection and replacement: The degreaser will gradually lose its effectiveness during use. Its cleaning effect should be regularly inspected and replaced in a timely manner to ensure process quality.

V. Conclusion

Degreasing agents play an indispensable role in aviation manufacturing, and their application runs through multiple links such as material pretreatment, parts processing, painting, and maintenance. By selecting appropriate degreasing agents and strictly following the process requirements, the quality and safety of aviation manufacturing can be effectively improved. At the same time, with the improvement of environmental protection requirements, environmentally friendly products such as water-based and bio-enzyme degreasing agents will be more widely used. Aviation manufacturing companies should continuously optimize the degreasing process and promote the development of green manufacturing.