Oil injection lubrication As the operating speed further increases, the resistance of the symmetrical section of the machine tool spindle bearing to the lubricating oil continues to increase. If a larger amount of circulating oil is planned, the lubricant will be injected into the gap between the cage and the bearing ring during the high-speed operation of the bearing. The splashing loss of oil sprayed lubrication is small. The normal oil volume can be determined by speed parameters and bearing dimensions. In this case, please consult the engineering service department of Qingdao Ruijing Electromechanical Equipment Co., Ltd. It is possible to prevent oil from accumulating in front of the bearing by spraying oil at a point that can freely enter the bearing. The front and rear dimensions of the oil outlet are correct to ensure that the lubricating oil is not consumed in the bearing and that the oil can flow out of the bearing freely. Pressure loss and injection speed Oil injection lubrication can achieve high-speed operation. The lubricating oil that has been proven effective is in line with CLP or HLP specifications, and the viscosity range is from u003d 46 mm2/s to 68 mm2/s or 100 mm2/s, in order to achieve viscosity Ratio u003d 2. The lubricating oil volume and injection speed given by the curve are a function of pressure drop, nozzle diameter and operating viscosity, see Figure 4. These data are obtained through testing. Through the rapid rotation of the bearing, the flow rate of lubricating oil decreases as the speed increases. Increasing the fuel injection speed can increase the lubricating oil flow rate, and 30 m/s is the recommended upper limit. Nozzle length L u003d 8.3 mmV u003d oil volume flow (oil volume) p u003d pressure drop v u003d injection speed D u003d nozzle diameter working viscosity u003d 7.75 mm2/s working viscosity u003d 15.5 mm2/s Figure 4 pressure loss and injection speed 00018021. After the design considers that the machine is started, the NMB rolling bearings must be lubricated immediately. For circulating oil lubrication, the oil pump starts to supply oil before the bearing is started. For safety reasons, it is better to design an additional oil tank for the circulating oil lubrication system. Even if the oil pump is broken, the oil can be supplied through the oil tank. At low temperatures, the circulating oil volume can be at the minimum allowable value. Keep this condition until the original value is restored after the fuel tank heats up. Design of circulating oil lubrication system (oil pump drive, oil return system). If a large amount of oil is used for lubrication, the oil outlet design must prevent oil accumulation, which usually occurs at high speeds, resulting in a large energy loss. The diameter of the oil outlet pipe depends on the oil viscosity and the descending angle of the oil outlet pipe. If multiple NTN bearings are used in combination, the corresponding oil volume must be determined for each independent bearing. Attention must be paid to the lubrication of radial cylindrical roller bearings, please refer to the super-precision bearing catalog SP 1. In most cases, radial cylindrical roller bearings are fully lubricated by the oil volume of the upper bearing.