What are the requirements for lubricating oil in ultra-high pressure polyethylene compressors? ?
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Requirements for lubricating oil in ultra-high pressure polyethylene compressors: During the production of ultra-high pressure polyethylene, the ethylene raw material is compressed to 3500 bar; the final compression stage employs reciprocating compressors, which are known as ultra-high pressure compressors.
The lubrication of reciprocating compressors should not be primarily dependent on pressure; rather, it is mainly related to the speed of rotation
The requirements for lubricants are quite strict; generally, domestically produced lubricants are not suitable. It is best to use those from Total and Shell. If the lubricant is not used properly, it can cause damage to the components, especially wear on the high-pressure plungers and plug sleeves, as well as significant wear on the packing
The lubricants for ultra-high pressure compressors are generally divided into three types: lubricant for the moving parts (external oil), cylinder lubricant (internal oil), and cooling flushing oil. The reference standards are as follows: For external oils (such as ISO VG 150), the viscosity index should be at least 80; the dynamic viscosity at 40°C should be between 135–165 CST (mm2/s). The flash point (open cup) should be at least 200°C. The moisture content should not exceed 0.3%, and mechanical impurities should not exceed 150 ppm. The neutralization value should be at most 0.2 mgKOH/g. For internal oils (such as CL1000), the dynamic viscosity at 40°C should be between 170–210 CST (mm2/s). The flash point (open cup) should be at least 200°C, and the neutralization value should be at most 5.5–7.0 mgKOH/g. For cooling flush oils (such as ISO VG 68), the viscosity index should be at least 90; the dynamic viscosity at 40°C should be between 61–74 CST (mm2/s). The flash point (open cup) should be at least 200°C℃
According to the information I found: in the production process of ultra-high-pressure polyethylene, the ethylene raw material is compressed to 3500 bar. The final compression stage uses high-speed reciprocating compressors, which are known as ultra-high-pressure compressors. Many different lubricants are used as oils for ultra-high pressure compressors, but polyether-based compressor oils are the most cost-effective for the following reasons. 1. Compared to white oil and polyisobutylene, polyethers dissolve in ethylene to a much lesser extent; as a result, polyether compressor oils have the following two advantages: a) the viscosity of the lubricating oil decreases to the smallest extent, and b) less lubricating oil is \"washed away\" in the area where the piston moves. This results in lower lubricant consumption and reduced need for compressor maintenance. Generally speaking, under the same operating conditions, the amount of polyether-based compressor oil required is less than half that of mineral oil or polyisobutylene. 2. Polyether compressor oil exhibits better lubrication properties and load-carrying capacity compared to white oil and polyisobutylene. It minimizes wear on the piston and gasket to the greatest extent possible. Users report that with polyether-based compressor oil, the typical service life ranges from 20,000 to 40,000 hours. 3. Compared to white oil, polyisobutylene, or a mixture of the two, polyether-based compressor oils exhibit very little change in pressure-viscosity, which means that they do not tend to solidify at high pressures. This post was last edited by xlxderun on 2009-3-11 17:46]
Comparison with polyisobutylene and mineral oil: Polyisobutylene and mineral oil are widely used. Generally, lubricating oil needs to be heated to 40 °C before it enters the cylinder; otherwise, its viscosity is too high and its flowability is poor. The consumption of polyisobutylene/white oil is much higher than that of polyether compressor oil, and its storage time is shorter. There can also be issues with interactions regarding additives in polyisobutylene/white oil. In the production of polyethylene films, it can be observed that the presence of a small amount of polyether compressor oil results in much better film properties compared to those achieved with polyisobutylene/white oil. Although the unit price of polyisobutylene/white oil is low, a much larger amount is required compared to polyethers. Furthermore, polyisobutylene/white oil used in the production of polyethylene for high-tension cables does not affect the insulation strength. Polyether compressor oil is the best choice among lubricants used in gas compressors.
All the information you provided refers to internal oil. The working conditions in internal oil fields are indeed quite harsh. The minimum requirements for internal oils that I am aware of are: corrosion resistance, use of mineral or synthetic oils, and the inclusion of antioxidants, rust inhibitors, and anti-wear additives. To achieve good water separation performance, it should not contain dispersing additives, even in small amounts. Also, I’m not sure what the concept of “20,000–40,000 hours” refers to; generally, the operating time of a compressor is estimated at 8,000 hours per year, so over 2.5 to 5 years? What is the service life of high-pressure metal packing? This is impossible! From what I know about several LDPE production facilities at home and abroad, including those in Maoming, Jinshan, Yanhua, Daqing, Qilu, Yangba, Formosa Plastics, and SABIC, the longest service life of their two-stage high-pressure metal packing elements is 2 years! Of course, it can be used for a longer period of time, but being able to use it for 4 years is already quite remarkable. This post was last edited by superblade on 2009-3-4 15:21]
It’s mentioned in the information provided by foreigners; for detailed details, contact me.
Those who need such oil products can contact me.
Those used include BP, Shell, etc.; it must be synthetic oil without any polar impurities····