What is the reason for the high noise of spur gear drive?

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In addition to running accuracy, load capacity and fatigue life, noise is also an important indicator of the performance of a spur gear drive. Noise not only affects the operating environment of the equipment, but also affects the gear transmission accuracy and the overall operation and transmission of spur gear drives. With the successive issuance of ISO14000 and ISO18000 standards, controlling its transmission noise becomes more and more important.

The reason for the high noise of spur gear drive

SG-I Spur Gear Slewing Drive

1. Influence of gear accuracy: Gear accuracy is often designed with economic benefits as the basis, ignoring the impact of accuracy on drive noise and backlash. When the gear accuracy cannot be reached, it will increase the operating noise.

2. Influence of gear width: Under the condition of constant torque, the noise curve gradient of large tooth width is lower than that of small tooth width, and the noise of small tooth width is relatively large.

3. Influence of tooth pitch and pressure angle: Small tooth pitch can contact more gears at the same time, the overlap of gears increases, and the noise is larger.

4. Influence of gear displacement coefficient: When the gear transmission performance is improved, the bearing capacity, the displacement coefficient, the central moment, etc. are not suitable for operation, it is easy to generate noise.

5. Speed ​​control: The noise of the spur gear drive is also different at different speeds. With the increase of the speed, the noise of the drive will also increase.

6. Influence of dynamic balance: Misalignment of assembly will lead to unbalanced operation of the shaft system, and in the state of semi-loose and semi-tight gear meshing, it will lead to aggravation of driving noise, and unbalanced gear assembly will affect the accuracy of the transmission system.

7. Loose or damaged parts: Looseness of individual parts during installation will lead to inaccurate positioning of the system, and abnormal meshing will cause shaft movement to generate vibration and noise. Damage to the transmission parts will also lead to inaccurate or unstable movement of the system, resulting in unbalanced moving parts and vibration and noise during high-speed movement.

8. Improper use or maintenance: Dirty impurities enter the drive and cause wear and tear, causing malfunction noise or improper lubrication, causing wear and tear to increase noise. After understanding why the spur gear drive is noisy, let’s take a look at the specific solutions.

Spur gear drive operation noise solution

SG-M Spur Gear Slewing Drive

1. Improve the precision of the drive gear and reduce the transmission error and equipment noise. Control tooth profile error. Reducing the roughness of the tooth surface can reduce the noise emission.

2. When the drive transmission space allows, increase the gear width, reduce the unit load under constant torque, reduce gear winding and reduce noise excitation, while increasing the gear width can also increase the bearing capacity of the gear and improve the bearing torque of the reducer .

3. The correct and reasonable selection of the displacement coefficient can not only make up for the central moment, avoid gear undercut, ensure that the concentric condition is met, improve the transmission performance of the gear, increase its bearing capacity and the service life of the gear, and control the operating noise.

4. Increase the hardness of the spur gear drive gear tooth surface. The high hardness of the gear tooth surface can reduce the possibility of gear deformation, and at the same time, it has a certain effect on reducing the driving noise.

5. Do a good job of shock absorption between the equipment and the drive to avoid resonance and noise between the fuselage and the foundation support and connecting parts. High toughness, high damping base materials can be selected to reduce noise and vibration.

6. Regularly repair the equipment, tighten the parts, find and repair the faulty parts in time, and replace the parts that cannot be repaired in time to stabilize the equipment and reduce the noise level.

7. Supplement lubricating oil in time, choose suitable lubricating oil, avoid equipment heating, wear and other failures caused by insufficient lubrication, and cause failure problems such as increased noise.

8. Keep the internal parts of the drive clean and prevent impurities from entering the spur gear drive and affecting the normal operation of the transmission system.

The above is all about the reasons for the loud operating noise of the spur gear reducer, and also includes specific solutions. There may be many reasons for the noise during the operation of the reducer. It should be noted that the influence of various aspects of the rotary reducer is from Reduce the impact of noise in many ways.

Will the slewing drive raceway be damaged? Causes of raceway damage and preventive measures

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The main structure of the slewing reducer is a structure in which the slewing bearing is used as a transmission follower and a mechanism attachment, and the slewing bearing itself is used to cooperate with the driving power source and the main transmission parts to complete the rotation, deceleration and driving. The slewing bearing is still one of the more critical components, so will the raceway of the slewing drive be damaged? Below, Xiaobian will give you a detailed introduction.

Will the raceway of the slewing drive be damaged?

Will be damaged. As an important component used by many construction machinery, the slewing reducer will inevitably have problems such as wear and fatigue damage during daily use. Because of its slewing structure, it is inevitable that the raceway will be damaged during work. . In addition to the insufficient rigidity of the raw materials in the manufacturing process, the reasons for the damage to the raceway may include unreasonable structural design and insufficient manufacturing accuracy of the reducer. Let’s take a look at it in detail:

VE Series Slewing Drive

Causes of damage to the slewing drive raceway

1. Heat treatment process

The processing quality of the rotary reducer itself is related to the manufacturing accuracy, heat treatment state, and axial clearance. What we usually ignore is the influence of the heat treatment state. In addition to the external force, the most important thing for the damage of the raceway is the depression and cracks on the surface of the raceway during its production. This is related to the hardness of the raceway surface and the hardness of the hardened layer and the core, and these factors are determined in the heat treatment process. For this reason, the depth of the hardened layer on the raceway surface is insufficient and the hardness of the core is low. A more critical factor in its raceway damage.

2. Structural rigidity of turntable

The key component that transmits various loads between the turntable and the chassis when driven by gears. The rigidity of the turntable itself is not large. It mainly depends on the rigidity of the chassis and the structure of the turntable that supports it. When the structural rigidity of the turntable is not enough, the turntable under large eccentric loads The deformation of the bottom plate connected to the slewing mechanism is more serious, which in turn causes the equipment load to concentrate on a small part of the rollers, thereby increasing the pressure on a single roller, resulting in the contacting raceway also bearing a large contact stress, which It is also one of the reasons for the damage to the raceway.

SE Series Slewing Drive

Preventive measures for rotary drive raceway

1. Pay attention to the rated load: the rotary drive should not be overloaded;

2. Correct model selection: Select the appropriate slewing drive according to your needs. When purchasing the slewing drive, you must strictly calculate the various parameters of the slewing drive, and select the turntable bearing that suits the actual needs. road damage;

3. Pay attention to maintenance: maintain regular maintenance, and regularly add lubricating oil to the rotary drive. Only through reasonable maintenance and maintenance can we ensure that the slewing drive raceway is not easily damaged and prolong the service life of the slewing drive.
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The above is the answer to the question about whether the raceway of the slewing drive will be damaged. It includes the reasons for the damage of the raceway and preventive measures. In fact, whether it is the drive device or the bearing itself, as mechanical parts, there is a certain fatigue limit, which should be based on Use the guide reasonably and maintain it properly, so as to better play the role and value of the equipment.

How many degrees can the slewing bearing temperature generally not exceed? Solutions for overheating

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The temperature of the slewing bearing directly reflects whether the bearing is running normally. If the bearing temperature is too high, it may directly reflect that there may be some kind of failure in the bearing, which directly affects the performance of the machine. So how many degrees can the slewing bearing temperature generally not exceed?

Under normal circumstances, the temperature of the slewing bearing should not exceed 70℃, because the allowable temperature of the lubricating grease of the slewing bearing should be less than 80℃. Let’s take a look at the normal temperature range of the slewing bearing and how to solve the problem if the temperature is too high.

slewing bearing

1. The normal range of slewing bearing temperature

The temperature of the slewing bearing is mainly limited by the heat-resistant temperature of the bearing steel, cage, sealing material and lubricant, and in general, the working temperature of the slewing bearing should not be higher than 95 ℃. The aforementioned slewing bearing temperature should not exceed 70°C is calculated based on the grease life. If the operating temperature increases by 15°C, the grease life will be reduced by half. Among the heat-resistant temperature limits of several materials that affect the temperature of the slewing bearing, the heat-resistant temperature of the grease is lower, so this is the upper limit.

The normal working temperature that ordinary bearings can withstand is between 40 degrees Celsius and 70 degrees Celsius, but the ideal working temperature of slewing bearings should be in the range of 40-60 degrees Celsius. The slewing bearing used in the low temperature environment can be used in the vacuum environment. The selection of the low temperature bearing does not affect the working performance of the bearing, and it can also be used normally at minus 60 ℃.

Surface temperature of slewing bearing: When the bearing is running under the specified working conditions, the temperature of the outer surface of the built-in bearing should not be higher than the temperature of the conveying medium by 20℃, and the upper limit of the temperature should not be higher than 80℃. The temperature rise of the outer surface of the externally mounted bearing should not be higher than the ambient temperature by 40°C. The temperature is not higher than 80℃.

The ambient temperature of the turntable: the temperature rise of the bearing shall not exceed the ambient temperature of 35°C, and the upper limit of the temperature shall not exceed 75°C.

After understanding how many degrees the slewing bearing temperature cannot generally exceed, let’s take a look at how we can solve the problem when the slewing bearing temperature is too high.

Slewing Bearings

2. The solution to the high temperature of the slewing bearing

A high temperature often indicates that the bearing is in an abnormal state. High temperatures are also detrimental to bearing lubricants. Sometimes bearing overheating can be attributed to the lubricant in the bearing. If the bearing is continuously rotated for a long time at a temperature exceeding 125°C, the service life of the bearing will be reduced. Factors that cause high temperature bearings include: lack of lubrication or too much lubrication, lubricants. There are impurities inside, the load is too large, the bearing ring is damaged, the clearance is insufficient, and the high friction caused by the oil seal, etc. The solution to the high temperature of the slewing bearing:

(1) Adjust the amount of grease injected

Too much or too little grease will lead to abnormal bearing temperature. Too little bearing grease will not be able to lubricate the bearing, which will cause internal wear of the bearing and cause temperature rise. At the same time, too much bearing grease will also cause abnormal heating of the bearing. Therefore, the injection amount of bearing grease should be adjusted.

(2) Replace the grease

The mixing of different types of grease may cause the grease to deteriorate and agglomerate, which will affect the lubrication effect and cause the bearing to heat up. If the grease is polluted by external dust, it may also destroy the bearing lubrication and cause the temperature to rise. The suitable bearing grease should be replaced in time. , and do a good job of bearing moisture-proof and dust-proof measures.

(3) Overhaul the cooling system

If the pipeline of the bearing is blocked, the oil inlet temperature and return water temperature exceed the standard, or the cooler is not suitable for the cooling effect, the bearing temperature will be too high. At this time, it should be replaced in time or a new cooler should be installed in parallel. The axial flow induced draft fan should also check the insulation and sealing of the core cylinder.

(4) Check the coupling

If none of the above problems exist, the coupling needs to be checked. The thermal expansion of the equipment during operation should also be considered when aligning the axial-flow induced draft fan and the hydraulic coupler. The impeller side of the induced draft fan expands due to heat, and the bearing box rises; during the operation of the hydraulic coupling, the temperature rises, the bearing box expands, and the bearing rises, so the motor should be higher when aligning, and the size of the reserved amount depends on the characteristics of the equipment and Depends on the operating temperature parameters.

The above is the reason why the bearing temperature is too high. By measuring the bearing temperature, it can also help us to find out the possible problems of the bearing in time. Therefore, it is necessary to continuously detect the bearing temperature, whether it is to measure the bearing itself or other key parts. If the operating conditions do not change, all temperature changes can indicate a failure.