The working temperature of cylindrical roller bearings depends on many factors, including the heating capacity of all relevant heat sources, the heat flow rate between heat sources and the heat dissipation capacity of the system. Heat sources include bearings, sealing rings, gears, clutches, oil supply, etc. Heat dissipation depends on many factors, including the material and design of shafts and bearing pedestals, the circulation of lubricating oil and external environmental conditions. These factors will be introduced in the following chapters. Under normal working conditions, most of the torque and heat of bearing models come from the dynamic loss of elastic fluid at the contact part of roller / bearing ring. Heating is the product of bearing torque and speed. Use the following formula to calculate the calorific value. Qgen = k4n m tapered bearings can calculate the torque using the following formula. M = k1G1 (n μ) 0.62 (PEQ) 0.3, where: K1 = bearing torque constant = 2.56 x 10-6 (the unit of M is Newton meter) K4 = 0.105 (the unit of qgen is w, and the unit of M is Newton meter) non conical bearing. The calculation method of torque is given in the following chapters.
Heat dissipation: how to determine the heat flow of bearings in special applications is a complex problem. Generally speaking, it can be considered that the factors affecting the heat dissipation rate include: 1. The temperature gradient from bearing to bearing pedestal. This factor is affected by the size of the bearing pedestal and external cooling devices (such as fans, water cooling devices, etc.). 2. Temperature gradient from bearing to shaft. All other heat sources, such as gears and other bearings and adjacent components, will affect the temperature of the shaft. 3. Heat taken away by circulating oil lubrication system. To some extent, factors 1 and 2 can vary depending on the application. Heat dissipation modes include heat conduction in the system, convection on internal and external surfaces, and heat radiation between adjacent structures. In many applications, heat dissipation can be divided into two parts - the heat carried away by circulating oil and the heat dissipated through the structure. The heat taken away by the lubricating oil is easily controlled by the circulating oil system. In the splash lubrication system, the cooling coil can be used to control the lubricating oil temperature.
The heat taken away by the lubricating oil in the circulating oil lubrication system can be calculated by the following formula. Qoil = k6 Cp ρ f ( θ o - θ i) Where: K6 = 1.67 x 10-5 (the unit of qoil is w) = 1.67 x 10-2 (the unit of qoil is btu/ min). If the circulating lubricating oil is mineral oil, the heat taken away can be calculated by the following formula: qoil = K5 f（ θ o - θ i) The following coefficients apply to the heat and heat dissipation formulas listed on this page. Where: K5 = 28 (qoil unit is w, F unit is l/ minute, θ In ° C).
