best bearing slewing ring manufacturers china

The importance of the mutual difference between the two channels of the double volleyball slewing ring bearing

Slewing ring bearings have unique bearing characteristics, and are usually used in hoisting machinery, excavators, turntables, wind turbines, and other equipment. Most of the slewing bearings below three meters have a four-point ball structure, and the size of the load determines the height of the slewing ring, Diameter and size of channel steel balls.

If a large-load slewing ring bearing is required but the diameter is limited, the bearing capacity of the slewing bearing can generally be improved by increasing the steel ball. If the bearing capacity is still not met by increasing the steel ball, the structure of the double-row ball slewing bearing can be adopted.

The slewing ring satisfies the limited outer diameter size, but also requires a large load, which not only saves materials, but also improves the performance of the slewing bearing, so that the slewing bearing has greater axial radial load and tipping moment.

The channels of slewing ring bearings are divided into plane channels and arc channels, among which the channels of four-point contact ball bearings and double-row ball bearings are typical arc channels; the channels of crossed roller and three-row roller bearings are is a typical planar channel.

In terms of processing technology, the processing difficulty of circular arc channels is greater than that of flat channels, so there are naturally higher requirements for precision level and parameter control of actual processing.

Especially for the double-row ball slewing bearing, the channel is two parallel arcs. In theory, the two rows of balls are subjected to force and run at the same time during the rotation process, but the probability of absolute simultaneous force and simultaneous operation is very low. exist on.

During the machining process, a certain error is allowed in the double-row ball channel. This error is not enough to affect the overall running state of the slewing ring.

This mutual difference is generally required to be within 0.03mm in the process. In order to achieve this goal, in the process of bearing grinding and matching, the machine tool needs to have good precision, and the workers need to have a skilled operation level.

If you want to achieve zero or negative double-ball clearance, the difference needs to be controlled within 0.01mm. Inside, for the double volleyball slewing ring, only by controlling the mutual difference between the channels can the slewing ring exert its theoretical bearing capacity and its characteristics.

2.How to reduce slewing ring bearing tooth noise

The slewing ring bearing can stably support the equipment for slewing motion, also known as the turntable bearing. The mechanical equipment needs to be rotated without the transmission. The slewing bearing can be made of external teeth or internal teeth, and the rotation of the slewing bearing is realized through the gear transmission.

In practical applications, the force of the slewing bearing is different, the speed of rotation is also different, and the teeth of the slewing bearing are also different. In the process of gear transmission, the contact between the gear and the ring gear of the slewing ring will generate noise, so how to reduce the noise of the slewing ring?

1. Control the tooth precision. Through long-term practice, we found that if we want to reduce the tooth noise, the tooth precision needs to be controlled at 7-8 grades. The higher the rotational speed, the higher the gear tooth precision requirements. Gear, tooth accuracy should be controlled within 7 grades.

2. Reduce the frequency of start-stop or forward and reverse rotation of the gear. Frequent start-stop or forward and reverse rotation will cause the gear to vibrate too fast, and the vibration will generate noise. The faster the vibration, the louder the noise. Reduce noise.

3. Reduce the impact load. The impact load will make the vibration frequency and torsion direction of the gear different, which will cause vibration in the circumferential direction, which will form a smooth noise. Reducing the impact load can reduce the noise.

4. Reduce the occurrence of resonance, which will generate high-frequency noise. When the motor rotates at a low speed or at a certain speed, the equipment will resonate, causing the gear and ring gear to oscillate at a high frequency and the two oscillating objects will contact. High-frequency noise will be generated, which can generally be reduced by changing the speed or adjusting the position of the equipment.

5. Increase the roughness of the tooth surface. If the roughness of the tooth surface is very poor, it will cause point contact on the tooth surface, and noise will be generated when the high point contact is made. If the roughness of the tooth surface is increased, the tooth surface will be in line contact, and the noise will be very high. Small.

6. Increase the lubrication of the tooth surface. Insufficient lubrication will lead to increased friction, and noise will be generated when the tooth surface is rubbed. Sufficient lubrication can reduce friction and effectively reduce noise.