The sliding bearing lubrication knowledge - bearing

Lubricant lubricant is to reduce friction, reduce wear and tear, cooling and vibration absorption, lubricant with liquid, solid and gas and semi-solid, liquid lubricant known as lubricating oil, half of the solid, the oil cream for grease at room temperature. Lubricating oil is the main lubricant of lubricating oil, lubricating oil viscosity is the main physical performance indicators, internal friction performance characterization of fluid viscosity, the greater the viscosity, the liquidity is poor. Another physical properties of lubricating oil is oily, characterization of lubricant in metal surface adsorption ability. The greater the oily, for metal adsorption ability stronger, more easy to form the oil film. The choice of the lubricating oil should be comprehensive consideration of the bearing capacity, shaft speed, lubrication method, the surface roughness of the sliding bearing and other factors. General principles are as follows: 1, under the condition of high speed light load of work, in order to reduce the friction power consumption can choose low viscosity lubricating oil; 2, under the condition of overloading or impact load work, should use oily big, viscosity of lubricating oil, to form a stable lubricating film; 3, static pressure or sliding bearing of dynamic and static pressure can choose low viscosity lubricating oil; 4, rough surface, or without the running-in surface should be choose the lubricating oil with high viscosity. The selection of the hydrodynamic lubrication bearing lubricating oil viscosity, can be calculated for checking. Grease shaft speed is less than 1 m/s ~ 2 m/s of the sliding bearing can use grease, grease with mineral oil, all kinds of thickeners, Such as calcium, sodium, lithium, aluminum and other metal soaps) Mixed with water, and the consistency of the grease ( Penetration) Big, large carrying capacity, but not stable physical and chemical properties, should not be used under the condition of temperature change is big, more used in or oscillating bearing of low speed and heavy loading. Solid lubricant and gas lubricant solid lubricant is graphite, molybdenum disulfide ( 二硫化钼) And polytetrafluoroethylene ( PTFE） Wait for a variety of species. Under the condition of overloading, or used in high temperature working conditions. Gas lubricant used air, more used in high speed and can't use lubricating oil or grease. Lubrication method to provide bearing lubricant is the necessary condition to form the lubrication film, static pressure bearing and static pressure bearing is through the oil pump, choke and oil groove continuous oil supply to the sliding bearing shell, forming oil film makes the bearing and shaft neck surface separately. Dynamic pressure of the sliding bearing oil film is to rely on the rotation of the shaft neck be brought into the lubricating oil bearing clearance, its oil supply way has continuous and intermittent drainage oil. Intermittent oil: intermittent oil can be used oil can filling and lift of the needle valve by oil cup of oil, grease lubrication can only adopt the intermittent supply. Pressure type pressure oil cup screw sleeve type lubricating oil cup needle valve type continuous oil lubricating oil cup: core Nian oil supply oil ring oil supply pressure oil supply choice principle: the sliding bearing lubrication way can be determined based on the coefficient k type: p = F/( dB) - - - - - - - - - - - - The average pressure ( MPa） ; v - - - - - - - Shaft linear velocity ( m/s） 。 k≤2- - - - - - - In lubrication system, oil lubrication; k=2— 16 - - - - - - - Needle valve type lubricating oil lubrication; k=16— 32 oil ring or splash lubrication; k≥32- - - - - - - Pressure lubrication cycles.