Wind turbine is an important equipment in the process of energy conversion. Shaft is a very important part of wind turbine. And the shaft wear of wind turbine is a common problem of this equipment. Once this problem occurs, the user needs to face a series of problems in disassembly, return to the factory or repair welding. The repair cycle of wind turbine shaft wear is relatively long. So can the wind turbine shaft wear be repaired online on site?
The answer is yes! So how can we do that? Let's first look at two classic cases of wind turbine shaft wear.
During the regular inspection of a wind turbine in a power plant, it was found that the bearing position on the transmission side was abnormal. After dismantling and inspection, it was found that the diameter of the bearing seat was worn by 2mm. And there were many pits in some parts. The motor power is 1500kw, the bearing model is 6330M/C3, the motor speed is 1700r/min, and the transmission ratio is 1:99.7.
The reason for the wear of the shaft diameter of the wind turbine is that the pits on the shaft are caused by electrical corrosion. And the equipment uses an insulating end cover instead of an insulating bearing.
A company's 1.5MW wind turbine rotor shaft support side bearing has serious wear. Generator power: 1500KW. Bearing model: 6330-M-J20C-C3. Bearing diameter: 150mm. Bearing width: 65mm. Wear depth: 1.5mm. Equipment speed: 1800r/min. Operating temperature: 60°C~70 °C.
The wear is due to the damage of the shaft diameter during maintenance and replacement of bearings. After the operation, the axial movement of the bearing is caused by the vibration of the rotor shaft, which causes wear on the bearing position. The manifestation is that the bearing temperature rises abnormally during operation. And at the same time it causes wear to the outer gland of the bearing.
The above two cases are common problems with wind turbines. So how these problems should be solved? There are actually two ways to repair the wind turbine shaft without disassembly. Next, we will introduce these two methods one by one.
Method 1: On-line repair process of wind turbine shaft wear.
Surface treatment: The surface is treated with oil until the oil is carbonized. Polish the repaired surface with a sander to ensure that the surface is roughened to increase the adhesion. Clean the repaired surface with absolute ethanol.
Air test tooling: Check whether there is a gap on the joint surface, and whether the tooling can be rotated after it is installed in place, so as to ensure that there is no error in the matching of the tooling. Disassemble the tooling and brush the inner surface with release agent SD7000 for spare.
Reconcile the coating material: Mix carbon nano-polymer materials according to the proportion, and blend until it is uniform and has no color difference. Apply the blended material on the repair surface and install the tooling in place.
Material curing: Heating and curing, improve material properties and speed up material curing time.
Grind the size, and the repair is completed: Disassemble the tooling, verify the repair size, assemble the bearing after confirming that it is correct, and the repair is completed
There is one more method you can have a try.
Method 2: Repair the shaft diameter wear of the wind turbine without disassembly.
Preliminary cleaning of the shaft surface, wipe off the oil on the worn surface, and remove high spots, burrs, rust layers, etc.
The carbon nano-polymer material is blended in proportion until it is uniform and no color difference.
Apply the blended material on the repair surface, and install the tooling in place.
Heat curing, improve material properties and speed up material curing time.
Disassemble the tooling, verify the repair size, assemble the bearing after confirming that it is correct, and the repair is completed.
Although we have introduced two methods about solving wind turbines shaft wear, it is not an easy case to work. Just as we have mentioned at the beginning, wind turbine’s shaft is very important for the equipment. You can’t be too careful in this matter.