What to do if Perfluoropolyether grease is too sticky? This article will show you the complete analysis from the cause to the solution

Perfluoropolyether grease has excellent high temperature resistance, chemical corrosion resistance and wear resistance, and is often used in extreme environments (such as aerospace, semiconductor equipment, precision instruments, etc.). However, if it is found to be too viscous during use, it may affect the lubrication effect or equipment operation. The following is a detailed analysis and treatment method for its "too sticky" problem:

Analysis of the reasons for excessive viscosity

1. Improper selection of base oil viscosity: The viscosity of perfluoropolyether grease is determined by the viscosity of the base oil (perfluoropolyether). If the viscosity grade of the selected base oil is too high (such as ISO viscosity grade greater than 460), it will show obvious stickiness at room temperature.

2. Excessive thickener content: The content of thickener (such as polytetrafluoroethylene PTFE) in the grease is too high, which will increase the overall viscosity (such as NLGI grade exceeding No. 2), and thus appear more viscous.

3. The operating temperature is too low: The optimal operating temperature of perfluoropolyether grease is usually -20℃~260℃. If the ambient temperature is lower than its applicable lower limit, the fluidity of the base oil decreases, which will cause the grease to thicken.

4. Contamination or deterioration: After the grease comes into contact with water, dust or chemical media, the structure may change, resulting in an abnormal increase in viscosity.

Specific treatment methods

1. Adjust the use environment or increase the temperature under working conditions: If the viscosity is caused by low temperature, the grease can be restored to fluidity by preheating the equipment or increasing the ambient temperature. Reduce the load or speed: High-viscosity grease may increase friction under high-speed or heavy-load conditions. The operating intensity of the equipment can be temporarily reduced to observe whether the viscosity affects the performance.

2. Dilution treatment (caution required) Use special diluent: Perfluoropolyether grease needs to be diluted with fluorinated solvents, and avoid using ordinary organic solvents (such as ethanol, acetone) to prevent damage to the grease structure. Note: Dilution may shorten the lubrication life of the grease. It is only suitable for temporary adjustments, and it is recommended to operate under the guidance of professionals.

3. Replace the appropriate type of grease to reduce the viscosity of the base oil: choose a perfluoropolyether grease with a lower viscosity grade. Adjust the consistency grade: reduce the NLGI grade from No. 2 to No. 1 or No. 0, the consistency is softer and the fluidity is better. Consult the supplier: provide the equipment operating conditions (temperature, load, speed) and the existing grease model, and professionals will recommend the appropriate product.

Precautions

Avoid mixing: Mixing perfluoropolyether grease with other types of grease (such as lithium-based grease and silicone-based grease) may cause structural damage and aggravate the viscosity problem.

Safety protection: Wear gloves and protective tools during operation and operate in a well-ventilated environment.

Performance test: After any adjustment, the fluidity, lubrication effect and equipment operating temperature of the grease must be tested on a small range of equipment first, and then fully applied after confirming that there is no abnormality.