Oil-film bearings belong to a family of sliding bearings, which are in a state of full fluid lubrication under working conditions. Oil film bearings use the principle of fluid dynamic pressure lubrication, that is, relying on the relative movement of the shaft and the bearing components, with the help of the viscosity of the lubricating oil and the fluid dynamic pressure formed by the wedge-shaped gap of the oil in the bearing pair, the bearing that carries the oil film is formed .
The bearing oil film is also called the pressure oil film. It balances the load, isolates the journal and the sleeve, converts the solid friction between metals into molecular friction inside the liquid, and minimizes friction and wear, so that it can be within the maximum range Meet the requirements of bearing pressure, impact resistance, conversion speed, rolling accuracy, structure size and service life.
Therefore, the oil film bearing lubrication is often expressed in the following three forms:

(1) When starting or stopping, although there is lubricating oil between the shaft and the bearing, because the moving speed is equal to or approaching zero, the hydrodynamic lubrication has not formed or gradually disappeared, and the shaft and the bearing must be in direct contact. Lubrication is even in a semi-dry friction state.

(2) During the operation of the rolling mill, mixed lubrication may occur due to vibration, excessive water intake, insufficient oil supply, or oil quality problems.

(3) When the rolling mill runs normally and smoothly, it is fluid lubricated.
Therefore, the lubrication feature of oil film bearings is the mixed lubrication of the above three conditions alternately.
In order to meet the needs of high-speed, heavy-load, automation, large-scale and high-yield steel enterprises, to solve the lubrication requirements of rolling mill oil film bearings, and to meet the increasingly demanding working conditions, oil film bearing oil, the lubricant used in rolling mill oil film bearings, came into being.
1. Performance requirements of oil film bearing oil
The lubrication characteristics of rolling mill oil film bearings determine that the oil film bearing oil must meet its performance requirements in order to ensure the normal operation and continuous production of the rolling mill. Therefore, the price of the steel slag ball mill. Oil film bearing oil needs to have:
(1) Excellent viscosity-temperature performance (high viscosity index), which can still achieve normal lubrication of various lubrication parts when the bearing temperature changes greatly.
(2) Excellent anti-emulsification performance (ie water separation), which can quickly separate the water in the oil during long-term use.
(3) Good anti-wear and extreme pressure performance. When a small amount of water is mixed into the oil during operation, the jaw breaker will be broken. It can still form an oil film to maintain heavy load and anti-wear performance.
(4) Good anti-wear, anti-rust and anti-foam properties, prevent the lubrication system from rusting, blocking the oil circuit, causing wear and insufficient oil supply.
(5) Good oxidation stability, cleaning and filtering properties. Make the lubrication system's oil path unblocked and ensure normal lubrication.

2. Lubrication management and use requirements of oil film bearing oil
The data shows that more than half of the main causes of mechanical failure or early wear are related to the management of lubrication technology. Do a good job of lubrication management, prevent frictional movement parts such as bearings, gears, etc. from scratching or sintering, prevent and reduce wear, reduce friction resistance, roller crushers. Preventing the occurrence of equipment accidents, improving equipment production efficiency; saving energy, improving energy efficiency, and increasing economic benefits are the main tasks of lubrication management.

1) Lubrication management is a professional technical management. Full-time lubrication technical management personnel should be established, a lubrication management system should be formulated, and training of lubrication technical knowledge should be carried out.
2) Under the premise of a reasonable fuel tank capacity, maintain a reasonable oil level in the fuel tank, often add lubricating oil to the fuel tank, so that the oil in the fuel tank is always at a reasonable operating level, degass the oil, settles the engine, and separates the moisture and water. It is beneficial to reduce the oil temperature in the tank.
3) Regularly and locatingly extract oil samples during operation, and conduct inspection and testing from the oil odor, color, viscosity change, water content, water separation performance, pollutant type and content, and anti-foaming performance. When the water content of the oil entering the lubrication point exceeds 0.1%, mechanical wear will increase sharply; when it exceeds 0.5%, the lubrication condition will be very dangerous. Compare the jaw crusher. Make inspection records.
4) Analyze and compare each inspection record, predict and forecast the bad lubrication state, and formulate improvement or preventive measures. The system's oil level, oil quality, oil temperature, oil pressure control alarm and interlock must be safe and reliable to prevent lubrication accidents.
3. Prevent oil mixing and control oil pollution
(1) Purchasing, warehousing, storage, delivery, and waste oil treatment should have a strict management system, which should be carried out according to different varieties and grades, with obvious and easily distinguishable signs or signs, indicating the product name, grade, date, etc. . Mixed storage is strictly prohibited to prevent misuse from causing mixing accidents.
(2) During storage, transportation and storage, the containers must be strictly kept clean and airtight to prevent the intrusion of dust, impurities, and rainwater. It should be stored in a dark, cool and well-ventilated warehouse with fire-fighting passages. When temporarily stored in the open air, the lid of the bucket should be kept in a slightly inclined position to prevent rainwater from intruding. Oil products should not be in contact with metals that promote oxidation reactions, such as copper and lead.
(3) The main items of lubricating oil acceptance and re-inspection: viscosity, viscosity index, water content, demulsibility, extreme pressure. Cleanliness requires mechanical impurities within 0.01%, without traces of moisture and sediment, etc.
(4) The manhole cover on the top of the fuel tank should be tightly covered and not open. The installed air filter has a filtering accuracy of more than 100 meshes and is regularly inspected and cleaned. The drain valve at the lower part of the fuel tank discharges regularly. Fill the oil tank with lubricating oil by pipe pumping, and install a filter with proper filtration accuracy. The fuel tank should be cleaned regularly of sedimented sludge, and it is not allowed to wipe the inner surface of the fuel tank with fabric with fibers.
(5) When replacing a clogged filter element, drain the oil in the filter cartridge to prevent dirt from entering the downstream pipeline of the filter, causing serious irreparable secondary pollution, otherwise it will directly endanger the normal lubrication at the lubrication point.
(6) Change the oil on time and according to the quality according to the changes in indicators such as the color, viscosity, moisture, and pollution of the oil in use.
4. Use oil film bearing oil for the first time
In addition to the complete and thorough cleaning of the original lubrication system and equipment, the following tasks must be done:

(1) Compare and analyze the standard values ​​and actual test values ​​of the physical and chemical performance indicators of the oil film bearing oil with the physical and chemical indicators of relevant domestic and foreign manufacturers' oil products, and combine the working conditions of their own equipment to formulate alternative work plans and unexpected situations Technical measures at the time of occurrence are foolproof.
(2) The oil use department should organize relevant technical personnel to analyze and discuss oil product technical data in order to fully understand the performance of the oil product and the correct use method.
(3) The mixing test of new oil products and in-use oil products should record the objective conditions of the compatibility or chemical reaction between the two and the changes in oil quality, and test the relevant physical and chemical performance data.