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Over the last decade, the field of wind energy has undergone signifi cant changes, the aim and result of which has been a drastic dimensional increase of the wind power plants to increase their performances. An example is the new project for a fi ve-megawatt power plant with a tower height of 127 m. The blades of this wind power plant are 71 m long and create a circle with a diameter of 145 m. At the same time, alongside with the increase in the power of the wind turbines, various new concepts for the mounting the main shaft were proposed. The version with a single main bearing, also called as three-point, has a gearbox attached to the frame by means of pins, where the main bearing is located on the side closer to the rotor with the blades and the rear bearing is installed directly inside the gearbox. In the version with two main bearings, the rear main bearing is located just in front of the gearbox, which is directly mounted on the main shaft. From the point of view of input costs, the variant with two main bearings is more demanding, however, this type of arrangement is more reliable, because the gearbox does not transmit reaction forces and pure torque enters it. In addition, this method of mounting is not so prone to misalignments and deformations of components. In both described arrangements, the bearings must not only transmit the load generated by the impact of the wind on the blades, but also bear the weight of the shaft and of the gearbox. The main bearings are one of the key components of the wind power plants, which is why customers put huge emphasis on high operational reliability.

近十年来，风能领域发生了重大的变化，由于风场规模的急剧增加，对于风机的性能和尺寸有了更高的要求和标准。 以一座塔高127m的5兆瓦风力发电厂的新项目为例，该风力发电厂的叶片长71m，形成直径145m的圆，同时随着风力涡轮发电机功率的增加，提出了安装主轴的各种新概念。一种方式是单个主轴承，也被称为三点式，单个主轴承是通过销钉固定在机架的齿轮箱上， 其中主轴承位于靠近带叶片转子的一侧，后轴承直接安装在齿轮箱内部。在有两个主轴承的方式中，后主轴承位于齿轮箱的正前方，齿轮箱直接安装在主轴上。从投入成本的角度来看，两个主轴承的型式要求更高，但这种布置方式更为可靠，因为变速箱不传递反作用力，而纯扭矩会进入齿轮箱。此外，这种安装方法不易造成部件的错位和变形。在上述两种轴承安装方式中，轴承不仅必须传递风对叶片冲击产生的载荷，而且还必须承受轴和齿轮箱的重量。主轴承是风力发电厂的关键部件之一，这也是客户非常重视高可靠性运行的原因。