The guarantee of wind power slewing bearing quality is mainly reflected in the design and manufacture. It integrates domestic and foreign enterprises and institutions to design and manufacture wind power slewing bearings. We have made key technologies for the design and manufacture of wind power slewing bearings. Research, a brief introduction, I hope to be able to help related companies and designers.
First, the design of wind power slewing bearing
The selected slewing bearing generally has a single-row four-point contact ball type, a double-row four-point contact ball type, a cross-roller type, a three-row type of roller type, etc., wherein the single-row four-point contact ball type slewing bearing has a low cost, and The comprehensive performance is high; the double volleyball type slewing bearing has long service life, strong carrying capacity, small turning resistance, large wear amount, low requirements on the mounting base, but low motion precision; high precision of the cross roller type slewing bearing Long service life and high dynamic load capacity, but high requirements on the rigidity and precision of the pedestal, and the edge effect is easy to occur when the roller and the raceway are in contact, resulting in the edge actual stress being much larger than the design stress; three-row roller type Slewing bearings generally have a very high static load carrying capacity.
Second, the manufacture of wind power slewing bearing
Wind power slewing bearings, especially the choice of pitch slewing bearings, many large multinational companies are still studying, from the current installed use situation, the pitch slewing bearings mostly use double-row four-point contact ball slewing, The yaw slewing bearings are mostly single-row four-point contact ball slewing bearings, and a small number of cross-roller slewing bearings or other forms. Although the domestic standard specifies the structural form of pitch and yaw slewing, it does not give a reasonable explanation.
1. Life calculation The wind power slewing bearing has a large size and low rotation speed. The life evaluation criteria of ordinary bearings are not applicable to the slewing bearing in many cases. At present, there are usually two methods for solving the life of a slewing bearing: one is the slewing bearing capacity curve method, and the other is the equivalent dynamic load method.
2. Carrying capacity curve method Using the slewing bearing capacity curve method to solve the life of the slewing bearing, firstly, the intersection of the axial force and the overturning moment should be marked in the bearing capacity curve as the slewing bearing specification is selected, and the coordinate origin and intersection point are connected. Extending, the extension line and the bearing capacity curve are intersected to obtain the moment and axial force of the intersection point, and the ratio of the load to the actual load on the curve is solved, and the actual life is the curve rated life multiplied by a coefficient related to the ratio.
The slewing bearing used in wind power generation equipment is a kind of extra large bearing, which is mainly used for pitch and yaw system. The load is complicated and the disassembly and maintenance is very difficult. Therefore, the design and manufacture of wind power slewing bearing are strict. The slewing bearing is the core component of the wind turbine and is widely used in the pitch and yaw systems of wind turbines.
The pitch bearings are used to connect the wheel and the blades, and the yaw bearings are used to connect the tower and the unit. Due to its large size and difficult installation and disassembly, the wind power slewing bearing is very difficult to repair, and once the slewing bearing fails, it will directly affect the working performance of the wind turbine and even cause downtime. Therefore, the wind power slewing bearing is required to have high reliability and long service life, and at least to reach the service life of the wind power generator, that is, 20 years.