Requirements for Bearings in Diesel Generator Sets

As a power supply equipment, diesel generator sets consist of different components. Bearings are indispensable parts ensuring the efficient operation of generators; high-quality bearings can improve generator efficiency and extend equipment service life. Dingbo Power Generator Manufacturer elaborates on the four key requirements for high-quality bearings as follows:

1.Bearing Gear Ring

Generally, the gear accuracy grade is required to be Grade 9 or 10 in accordance with GB/T10095.2-2001. However, due to the impact between the pinion and the bearing gear ring during operation, the tooth surface of the diesel generator bearing gear ring must be quenched. The tooth surface hardness of the pinion is typically 60HRC; considering equal life design, the quenched tooth surface hardness of the large gear is specified to be no less than 45HRC.

2.Low-Temperature Impact Energy

The standard requires that the low-temperature impact energy of yaw and pitch slewing bearing rings shall have an Akv value of not less than 27J at -20°C, while the Akv value under cold conditions can be determined through negotiation with the user. Generator sets may operate in extremely cold regions where the bearing working temperature is around -20°C. Bearings must withstand large impact loads under low-temperature conditions; therefore, the bearing ring material must undergo a low-temperature impact energy test after quenching and tempering. Test specimens shall be taken from the bearing rings or prepared under the same performance and heat treatment conditions as the rings, and the impact energy test shall be conducted at -20°C.

3.Internal Clearance

Yaw and pitch bearings have special requirements for internal clearance. Compared with yaw bearings, pitch bearings are subject to larger impact loads and greater vibration caused by wind acting on the blades. Therefore, pitch bearings are required to have zero or slightly negative internal clearance to reduce fretting wear during vibration. Yaw bearings require small internal clearance, specifically 0-50μm. Additionally, since the rotation of both yaw and pitch bearings is driven by drive motors, the bearings must allow the drive motor to operate normally even under negative or small clearance conditions. Thus, the no-load starting friction torque must be measured after bearing assembly, with specific torque values varying depending on the main drive system.

4.Anti-Corrosion Treatment

High-humidity environments can also corrode the bearing substrate. Therefore, exposed parts of yaw and pitch bearings require surface anti-corrosion treatment, typically galvanization. If necessary, a paint coating may be applied over the galvanized layer for additional protection.

Dingbo Power has advanced testing equipment, modern production technology, professional manufacturing technology, perfect quality management system, and strong technical research and development capabilities. It can provide 3KW～2500KW various specifications of ordinary, automatic, four protection, automatic switching, low noise and mobile generator sets, high quality and low energy consumption to meet the diverse power needs of customers, and can also meet users with different voltages and different frequencies. It is required to create a parallel power supply system for multiple units. If you are interested in our product or any question on generator, welcome to send email to [email protected].