Tapered roller bearing mounting method and heating installation points

　A, tapered roller bearing installation method
　　
　　1、Press-in fit
　　
　　If the inner ring of the bearing is tight with the shaft, and the outer ring is loose with the bearing housing, the bearing can be pressed into the shaft, and then the shaft will be installed into the bearing housing together with the bearing, and a soft metal casing (copper or soft steel) will be padded on the end of the inner ring of the bearing.
　　If the outer ring of the bearing is tightly matched with the housing hole, and the inner ring is loosely matched with the shaft, the bearing can be pressed into the housing hole first, and the outer diameter of the assembly sleeve should be slightly smaller than the diameter of the housing hole.
　　If the bearing collar and shaft and seat hole are tight fit, the inner ring and outer ring should be pressed into the shaft and seat hole at the same time, the structure of the assembly sleeve should be able to tighten the bearing inner ring and outer ring end face at the same time.

　　2、Heating fit
　　
　　By heating the bearing or bearing seat, the use of thermal expansion will be a tight fit into a loose fit installation method, is a common and labor-saving installation method. This method is suitable for the installation of the bearing with a large amount of interference. Before the hot installation, put the bearing or separable bearing collar into the oil tank and heat it evenly at 80-100℃, then take it out of the oil and install it on the shaft as soon as possible. To prevent the inner ring end face and shaft shoulder from fitting tightly after cooling, the bearing can be tightened axially again after cooling. When the outer ring of the bearing is tightly fitted with the bearing seat made of light metal, the hot installation method of heating the bearing seat is used to avoid abrasion of the fitting surface.
　　When heating the bearing with oil tank, there should be a mesh fence at a certain distance from the bottom of the box, or hanging the bearing with a hook, the bearing cannot be put on the bottom of the box to prevent sinking impurities into the bearing or uneven heating, the oil tank should have a thermometer, strict control of the oil temperature shall not exceed 100 ℃, in order to prevent the occurrence of tempering effect, so that the hardness of the collar is reduced.
　　
　　Second, tapered roller bearing heating installation method
　　
　　When the inner diameter of the bearing is greater than 70mm, or with a large interference, use the heating method to make the bearing hole expansion, so that the installation saves effort and time, but also to avoid the damage caused by the application of excessive force. At this time need to control is the heating temperature, generally the bearing heated to 80 ℃, 100 ℃. It is enough. More than 120 ℃ will lead to tempering phenomenon of the bearing, resulting in the hardness and accuracy of the collar is reduced. Commonly used heating methods are as follows.
　　
　　1, electric heating plate heating method: the bearing will be placed in the temperature of 100 ℃ electric heating plate for a few minutes, this method is simple, such as flipping several times can make the bearing heated evenly, and also high efficiency, size bearings can use this method.
　　
　　2, electric furnace heating method: the bearing will be placed in the closed automatic temperature control electric furnace heating, heating uniform, accurate temperature control, heating fast, suitable for a number of heating many bearings occasions.
　　
　　3, induction heating method: the use of induction heaters can be fast, reliable and clean bearing heated to the required temperature, which is particularly suitable for the inner ring tight with the occasion, due to be heated only the inner ring, while the outer ring heated very little, so that it can be easier to install on the shaft, but also easy to install into the seat hole.
　　
　　4, electric bulb heating method: the use of 50W electric bulb heating bearing, can ensure that the heating temperature at about 100 ℃, smaller bearings can be placed directly on the light bulb, larger bearings can be placed in the light bulb conical cover, conical cover can prevent the light bulb heat dissipation, and make heating uniform. Conical hood up and down can be adjusted, within a certain range can adapt to heating different sizes of bearings. If the far-infrared light bulb, note that the direction of the light bulb should be down, so as to avoid infrared rays adverse to the human eye. This kind of light bulb can save energy. Bulb heating method is suitable for a small number of infrequent need; to the bearing heating occasions, usually the bulb can also be used for lighting, in addition to not need any other equipment.
　　
　　5、Oil tank heating method: This is a widely used traditional heating method, oil tank from the bottom 50 ~ 70mm set metal mesh, bearings placed on the network, large bearings to be lifted by hooks. Bearings should not be placed directly on the bottom of the tank to prevent the bearing parts in contact with the bottom of the tank from being overheated locally, or the dirt deposited on the bottom of the tank from entering the bearings. The main points of attention of the oil tank heating method are as follows, non-corrosive thermal stability of good mineral oil should be used, is transformer oil, oil and container should be kept clean. The capacity of the oil tank should be with the size of the heated bearing and the amount of oil, if the container is too small, in continuous operation, a bearing into the oil temperature will drop quickly, the effect is not good.