Application of oil mist lubrication systems in high-temperature pumps and vertical pumps

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High-temperature pumps handle media at temperatures as high as 400°C. For the thin oil lubrication of bearings in such high-temperature media pumps, the temperature of the oil pool can reach up to 80°C. The heat generated by friction in the lubricating oil cannot be dissipated, and mechanical impurities such as metal particles on the friction surfaces cannot be removed, which increases friction and wear, thereby shortening the service life of the equipment. Pure oil mist lubrication is used, with no lubricating oil present in the bearing chamber; this eliminates the heat generated by friction from the lubricating oil, reducing the operating temperature of the bearings by 10–15°C. It also eliminates the potential risk of moisture or residues accumulating in the lubricating oil due to its repeated use, thereby extending the service life of the bearings by three times. In February 2009, Shenyang Jiayi Oil Mist Technology Company successfully applied an oil mist lubrication system to the atmospheric and vacuum distillation unit at Dalian West Pacific Petrochemical. The vacuum residue pump P20 was a 250AYS-150×2C(C-6) type pump manufactured by Shenyang Guotelong Pump Co., Ltd.; the normal operating temperature of the fluid was 377°C, with a maximum temperature of 420°C. The pump’s power was 204 KW. After the implementation of oil mist lubrication, the surface temperature of the pump decreased by 10°C, thereby extending the service life of the bearings. Among them, the crude oil pump P01 is a DSJH8×10×18H type pump manufactured by Shenyang Guotelong Pump Co., Ltd.; it has an electric motor power of 630 kw and a pump power of 506 kw. It has been operating successfully to this day and has received high praise from users. The lubrication of vertical pump bearings places high demands on the shaft seals, which in turn have a short service life. Even with grease lubrication, the increase in temperature resulting from long-term operation causes the grease to age, deteriorate, liquefy, evaporate, or be lost. If the seal fails, the grease in the upper part will melt and fall into the lower part of the bearing housing, leading to overheating of the upper bearings and eventual damage to them. Oil mist lubrication is used to address the aforementioned safety risks; moreover, it allows the surface temperature of the pump to drop by 10°C–15°C, and extends the service life of the bearings by three times.