Vacuum diffusion pump oil is a lubricant specially designed for vacuum diffusion pumps to ensure efficient operation and long-term stability of the pump. According to its chemical composition and performance characteristics, vacuum diffusion pump oil is mainly divided into the following categories:
1. Mineral oil vacuum diffusion pump oil
Mineral oil vacuum diffusion pump oil is extracted from natural petroleum and undergoes specific processing and treatment to meet the use requirements of vacuum pumps. This type of pump oil usually has good lubricity and sealing properties, is relatively cheap, and is a common choice for many industrial applications. However, the thermal stability and oxidation resistance of mineral oil pump oil may not be as good as synthetic oil pump oil, so more frequent replacement may be required under high temperature or extreme working conditions.
2. Synthetic oil vacuum diffusion pump oil
Synthetic oil vacuum diffusion pump oil is made by chemical synthesis and has more excellent performance characteristics. This type of pump oil usually has higher thermal stability, oxidation resistance and chemical stability, and can maintain stable performance under extreme working conditions. Synthetic oil pump oil also usually has a lower saturated vapor pressure, which helps to reduce gas leakage in the pump and improve the vacuum degree. Therefore, synthetic oil vacuum diffusion pump oil is more common in applications that require high vacuum or long-term stable operation.
Among synthetic oil vacuum diffusion pump oils, silicone oil is an important type. Silicone oil has a unique siloxane structure, which gives it excellent viscosity-temperature properties, low freezing point and volatility, and good thermal oxidation stability. These characteristics make silicone oil the preferred pump oil in many high vacuum and ultra-high vacuum applications. In particular, silicone oils with high phenyl content, such as DC702, 703, 704, 705, 706 and other foreign products, as well as similar products such as 274, 275, 275-1 in my country, are commonly used high-quality vacuum diffusion pump oils.
3. Other types of vacuum diffusion pump oils
In addition to mineral oil and synthetic oil vacuum diffusion pump oils, there are some other types of pump oils, such as esters, polyphenylene ethers, etc. These pump oils usually have specific performance characteristics and are suitable for certain specific applications. For example, ester pump oils may have better biodegradability and environmental performance, while polyphenylene ether pump oils may have higher thermal stability and chemical stability.
In summary, there are many types of vacuum diffusion pump oils, and the type of pump oil to choose depends on the specific application requirements and working environment. When selecting pump oil, factors such as the working conditions of the pump, the required vacuum degree, the performance characteristics of the pump oil, and the cost should be fully considered to ensure the long-term stable operation and efficient performance of the pump.