U.LUBE team on-site service: Lubrication improvement for open gear of Tungsten molybdenum ore ball mill
There are 5 sets of two sizes of lattice ball mills produced by Shenyang Heavy Industry in the beneficiation workshop of a tungsten and molybdenum mine plant (5# mill specification: Φ3.2m×4.5m, 1#~4# mill specification: Φ2.1m×3.0m), and the equipment transmission is driven by large open gears through edge drive; the large mill open gears are lubricated by injection, and the small mill open gears are lubricated by oil pool.
After U.LUBE team's on-site research, the original oil is a brand of 150/320# closed gear oil for operational lubrication with poor lubrication effect, resulting in different degrees of damage to the working surface of mill open gears. As for 1# to 4# mills (specifications: Φ2.1m×3.0m), tooth surface is dry with poor lubrication effect, tooth surface has different degrees of wear, oil in boundary lubrication conditions, the damage of the small teeth of mill #5 (Φ3.2m×4.5m) is more serious, and individual gear teeth have broken teeth.
1# Ball Mill：
From the state of the oil film on the tooth surface and the damage, the tooth surface is poorly lubricated and there is obvious wear on the tooth surface. Traces of gluing/scuffing from oil lubrication failure (insufficient extreme pressure anti-wear) are visible at the non-drive end. Wear steps are visible on both ends of the tooth surface, and the amount of wear is to be further confirmed. Combined with the data of tooth surface thermal imaging and temperature distribution, the preliminary judgment is that there may be biased load at the non-driving end of the tooth surface.
From the state of oil film on the tooth surface and the damage situation, the tooth surface lubrication is not effective, and the tooth surface has abnormal wear. From the analysis of the extrusion deformation of the top of the tooth and the root wear "depression", the tooth surface meshing gap has changed several times, and the tooth surface contact state has obvious abnormalities.
The tooth surface shape remains intact, and no obvious wear deformation is observed. The tooth surface is dry, and the lubrication condition needs further observation. It needs to focus on the tooth surface under the boundary lubrication condition, and the difference of oil adhesion and extreme pressure on the tooth surface lubrication effect.
From the analysis of the oil film state and damage degree of tooth surface, there is obvious wear on the tooth surface, there is abnormal change of tooth shape, traces generated by multiple wear are visible on the tooth surface, the lubrication and friction reduction effect of the oil on the tooth surface is poor, and traces of gluing/scuffing generated by obvious lubrication failure are visible on the tooth surface. It is necessary to pay attention to the effect of tooth shape change on the fatigue strength of tooth surface.
The tooth surface is poorly lubricated, and traces of galling/scuffing from lubrication failure are visible on the top of the tooth. The tooth contact near the pitch circle is heavy, and the pitting/spalling fatigue damage is concentrated, and the individual gear teeth at the end of the tooth face have fatigue broken tooth damage. It is necessary to focus on the influence of the "fatigue zone" near the pitch circle on the gear life and equipment operation status.
Lubrication improvement of ball mill open gear
The reasons for the current damage of 5 ball mill open gears of different degrees are complex and need to be combined with the installation of equipment, gear fitting, oil and the use of lubrication system for attention and analysis, among which the correct selection and use of lubricants has an important relationship.
Ball mill transmission gear is large open gear, its operating conditions are extremely harsh, in low speed / heavy load, and accompanied by impact load; easy to be affected by dust, but also accompanied by high temperature. Therefore, when choosing the lubricant, it is necessary to use the special lubricant that meets the lubrication specification of large open gears, in order to form the protective oil film of sufficient strength on its working tooth surface; at the same time, under the joint action of impact load and harsh working conditions, large open gears are often in the situation of boundary lubrication, which requires high requirements for lubricant, so it is necessary for the lubricant to have the function of high viscosity and emergency lubrication.
According to the characteristics of tungsten and molybdenum ore ball mill, with reference to the domestic and international open gear lubrication standards and specifications, and integrated with the mature experience of U.LUBE team on mill open gear technology service, we recommend to use U.LUBE brand ET series open gear operating lubricant ET G-OG C-1000, which has suitable viscosity base oil, appropriate proportion of extreme pressure (EP) additives and solid additives with laminar structure (such as solid additives with laminate structure (such as graphite), as well as suitable thickeners and some other special additives, can fully meet the comprehensive requirements of fluid lubrication, boundary lubrication and emergency lubrication. And combined with regular equipment testing, timely adjustment of equipment problems (installation problems, environmental problems, etc.), in order to make the equipment get good lubrication, and effectively extend the service life of the equipment.