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china wholesale slewing gear factory

1.Are bearing inner rings interchangeable? Can old and new slewing gear be mixed?

Are bearing inner rings interchangeable? When replacing old slewing gears, some manufacturers find that the reasons for the damage and failure of bearing accessories are different, and they want to know if the inner ring of the bearing is damaged, can the inner ring accessories of another bearing be replaced for combined use, and want to extend the bearing life in this way.

The frequency of use reduces the cost of replacing the bearing, but it is also worried that it will affect the service life of the bearing.

1. Can the inner ring of the slewing gear be interchanged?

The inner ring of the slewing gear is interchangeable. In fact, as long as it is the same type of slewing gear or the bearing inner ring with the same bearing suffix, it can be exchanged. In this case, do not replace the bearing’s outer ring type suffix.

The two types of slewing gears are different, so they cannot be replaced. If If it is found that the inner ring of the same model is mixed, it will not affect the quality and life of the bearing after assembly.

Some bearings fail due to various reasons, and some parts of the bearing are in good condition. At this time, it is possible to remove the outer ring of the bearing for use. However, some slewing gears themselves have bearings without an outer ring, and the inner ring of the bearing cannot be taken out independently. ,

At this time, it is recommended that customers do not blindly remove the outer ring to use, so as to waste the cost of an outer ring and increase itself. Replacement should be tried according to the specific conditions of the bearing.

2. Can old and new slewing gear be mixed?

For worrying about whether the operation of using old slewing gear parts to assemble new bearing parts will affect the service life or performance of the bearing, in fact, this also needs to be analyzed in detail. If there are no problems such as wear and deformation of the parts, the new and old bearing parts are suitable for use.

In the case of matching, it can be mixed. However, if the clearances of some accessories are different or do not fit, it is not recommended to mix them, and there may be poor operation or other wear and noise conditions that affect the normal operation of the slewing gear.

However, if the spare parts are of the same type, and there is no wear deformation or other faults after inspection, then the old and new bearings can be mixed.

slewing gear Alt.

2.What are the factors that affect the fatigue life of bearing steel?

Factors Affecting Fatigue Life of Bearing Steel

1. The effect of nitrides on fatigue life

Some scholars have pointed out that when nitrogen is added to the steel, the volume fraction of nitrides decreases. This is due to the reduction in the average size of the inclusions in the steel. Limited by technology, there are still a considerable number of inclusion particles smaller than 0.2 in. counted.

It is precisely the existence of these tiny nitride particles that has a direct impact on the fatigue life of slewing gear steel. Ti is one of the elements that form nitrides. It has a small specific gravity and is easy to float. There will also be a part of Ti left in the steel to form multi-angular inclusions.

Such inclusions are likely to cause local stress concentration and fatigue cracks, so it is necessary to control the occurrence of such inclusions.

2. The effect of oxides on fatigue life

The oxygen content in the steel is an important factor affecting the material. The lower the oxygen content, the higher the purity and the longer the corresponding rated life. There is a close relationship between the oxygen content in steel and oxides.

During the solidification process of molten steel, the dissolved oxygen of aluminum, calcium, silicon and other elements forms oxides. The oxide inclusion content is a function of oxygen.

As the oxygen content decreases, the oxide inclusions will decrease; the nitrogen content is the same as the oxygen content, and also has a functional relationship with the nitride, but because the oxide is more dispersed in the steel, it plays the same role as the carbide. , so it has no destructive effect on the fatigue life of steel.

Due to the existence of oxides, steel destroys the continuity of the metal matrix, and because the expansion coefficient of oxides is smaller than the expansion coefficient of the bearing steel matrix, when subjected to alternating stress, it is easy to generate stress concentration and become the origin of metal fatigue.

Most of the stress concentration occurs between oxides, point inclusions and the matrix. When the stress reaches a large enough value, cracks will occur, which will rapidly expand and destroy. The lower the plasticity of the inclusions and the sharper the shape, the greater the stress concentration.

3. The effect of sulfide on fatigue life

Almost all of the sulfur content in steel exists in the form of sulfides. When the sulfur content in the steel increases, the sulfide in the steel increases accordingly, but because the sulfide can be well surrounded by the oxide, the influence of the oxide on the fatigue life is reduced, so the number of inclusions has no effect on the fatigue life.

Certainly, it is related to the nature, size and distribution of inclusions. The more inclusions, the lower the fatigue life must be, and other influencing factors must be considered comprehensively. In bearing steel, sulfides are dispersed and distributed in a fine shape, and are mixed with oxide inclusions, which are difficult to identify even by metallographic methods.

Experiments have confirmed that, on the basis of the original process, increasing the amount of Al has a positive effect on reducing oxides and sulfides. This is because Ca has a fairly strong desulfurization ability. Inclusions have little effect on the strength, but are more harmful to the toughness of the steel, and the degree of damage depends on the strength of the steel.

best selling slewing bearing in stock

1.How does slewing bearing paint rust form? How to prevent?

Bearing paint rust often occurs in slewing bearings installed in closed equipment, generally manifested as rust inside the bearing and a strong paint smell.

Slewing Bearing paint rust is a frequent problem, which may affect the normal rotation and service life of the bearing. So how does bearing paint rust form, and how to prevent it every day?

First, the cause of the formation of bearing paint rust

Generally, the bearing with paint rust is generally on the end face near the inner side of the motor, and will be seriously rusted. The grease near the edge of the inner and outer rings will first deteriorate, generally yellowish brown.

The reason for the formation of bearing paint rust refers to the fact that during the slewing bearing paint rust test, it was found that the severity of bearing paint rust was closely related to the humidity. Most of the paint rust occurs in the south or the coast to coincide with the imagination of the annual rainy season.

1. The climate environment is high temperature and high humidity.

2. The stator drying is incomplete;

3. Motor bearings are sealed and packaged in storage;

4. The severity of paint rust mainly depends on the composition of the paint base.

5. Prevention of paint rust (bearing seal and rust prevention, type of grease).

Second, the prevention method of bearing paint rust

The prevention of bearing paint rust must be considered in terms of its mechanism, from the design and manufacture of motors, insulation and slewing bearings. We organize the preventive measures as follows:

1. Avoid complete sealing and open air holes as much as possible;

2. The manufacture of traditional Chinese medicine must ensure the drying time of insulating paint. After the stator is dried, it should be placed in a ventilated place for natural ventilation, so that the paint gas can be completely released. The stator should follow the principle of first-in, first-out during use.

3. During the storage process of the warehouse, it is not close to the walls and corners, and pallets are used on the ground to ensure ventilation, and the humidity should be less than 70%RH as much as possible.

4. Use stable insulating varnishes (such as epoxy solvent-free insulating varnishes) that do not escape low molecular acid, and produce them in strict accordance with the production process requirements.

5. When selecting grease, use mineral oil as the base oil.

6. Sealed bearings are used.

slewing bearing Alt.

2.What are the heat treatment processes for slewing bearings? Introduction of normalizing, annealing, quenching and tempering

1. Slewing Bearing heat treatment process

1. Quenching: Quenching is to heat the metal above the critical point. At this time, the internal structure and state of the metal will change – austenitization. At this time, it needs to be kept for a certain period of time to allow the metal to fully react, and then cooled at a rate greater than the critical cooling rate.

After quenching, the martensitic structure is obtained. Compared with before heat treatment, the material hardness is higher, but the brittleness and toughness are poor and need to be processed again.

2. Tempering: In order to solve the problem of poor brittleness and toughness of the material after quenching, tempering is generally carried out.

That is, after the metal is hardened, it is heated to a temperature below the critical temperature, kept for a period of time so that the internal structure of the metal can be evenly distributed, and then cooled to room temperature to obtain both a certain strength, hardness and a certain degree of hardness. Plastic and tough finished products.

3. Annealing: Annealing is to slowly heat the metal to a certain temperature, and then slowly cool it to room temperature, the distance is like if you boiled a bowl of noodles but it is too hot, so you should put it aside and let it cool before eating.

4. Normalizing: Normalizing is a heat treatment process in which the metal is heated to 30-50°C above the critical temperature, and then cooled in the air after being kept for an appropriate time. It sounds similar to the annealing process. Let’s find out together.

Second, the difference between normalizing and annealing

Normalizing is a variation or special case of complete annealing. The only difference between the two is the cooling rate. Usually, annealing is performed with furnace cooling and normalizing is cooling in air. Normalizing is suitable for both hypoeutectoid steel and hyperco-plate.

Steel, for eutectoid steel, normalizing is generally used to eliminate network carbide; for hypoeutectoid steel, the purpose of normalizing is basically the same as annealing, mainly to refine grains and eliminate defects in the structure, but the normalized structure Medium pearlite flakes are thinner than annealed ones, and the amount of pearlite in hypoeutectoid steel is more than that of ferrite.

Therefore, the hardness and strength of steel after normalizing are higher than those of annealed steel. It can be seen that in production practice, The materials with reticulated cementite in the steel need to be normalized and eliminated before other processes can be used.

For materials with performance requirements after heat treatment, the annealing process should be selected according to different requirements and different steel types,

such as: after heat treatment is required If there is a certain strength and hardness, the normalizing process can be selected; if a certain plasticity is required, the annealing process should be selected if the strength and hardness are reduced as much as possible.

top 1 selling slewing ring bearing ball made in china

1.The working principle of the slewing ring bearing

Slewing bearings are widely used in machinery, such as excavators, disintegrators, stackers and reclaimers, graders, road rollers, and roadheaders. Not only that, but also in new energy equipment, amusement equipment, metallurgical equipment, etc.

It also has its application in China, so what is the working principle and working method of the slewing ring bearing? Below, the editor will take you to understand some knowledge about slewing bearings, you can learn and understand.

First, the working principle of the slewing ring bearing

The working principle of the slewing ring bearing is to move the object from sliding to rolling to reduce frictional resistance. It mainly relies on lubrication and friction to achieve the purpose of operation. Internally, it relies on the mutual friction of balls and steel rings.

The friction between the slewing ring bearing and other parts runs, rubs against each other, and drives the object to operate. Although it relies on friction to operate, lubrication is also indispensable. If it is used for a long time and the friction is too large, it will also affect the application of parts.

Therefore, after using this kind of bearing for a period of time, it must be maintained in time. , brush some lubricating oil.

slewing ring bearing Alt.

2. How the slewing bearing works

1. Point contact scrolling
The working principle of point contact rolling is mainly used for four-point contact ball slewing ring bearing and crossed roller slewing bearing.

This working principle has higher requirements on the quality of steel balls for the combined bearing of point contact radial and axial forces, and the angle of the track should be uniform.

2. Rolling and sliding combined rolling type
The rolling-slip combined rolling working principle is mainly used for ball-column combined slewing bearings. This principle has small eccentricity and long service life, and has the advantages of a dual structure of rollers and balls.

3. Surface contact rolling and sliding combination
The working principle of surface contact rolling and sliding combination is mainly used for turntable bearings. Now the new type of turntable bearing has a compact structure and high precision, so it is suitable to use the surface contact rolling and sliding combination.

4. Surface contact rolling combination
The surface contact rolling combined working principle is mainly used for three-row roller slewing bearing, its advantage is that the contact surface is large, the bearing force is uniform and the rolling is flexible.

2.How to disassemble the large slewing ring bearing

Slewing bearing is a kind of large bearing with special structure. It can bear large axial load, radial load and overturning moment and other comprehensive loads at the same time.

It is widely used in various industries or equipment. Many friends are not very familiar with how to disassemble large slewing bearings.

Next, the editor of Hengguan will introduce the four commonly used bearing disassembly methods for you.

1. Knock Disassembly Method

The knocking method is used in many disassembly scenarios. Simply put, a copper rod or other soft metal material smaller than the inner diameter of the bearing is used against the shaft end (if the bearing is located at the end of the shaft), and a hand hammer is used to strike the inside of the bearing evenly and forcefully.

The ring slowly dislodges the bearing. This method is simple and easy to implement, but the disadvantage is that it is easy to cause damage to the bearing, so be careful when operating, and pay attention that the impact point of the knock should not fall on the rolling body and cage of the bearing.

2. Pull out disassembly method

This method requires the help of a special puller, and the tool can be pulled evenly by rotating the handle to pull out the bearing. This method has better protection for the bearing, and the following points need to be paid attention to during operation:

1. The hook of the puller should be hooked to the inner ring of the bearing. If it is hooked on the outer ring by mistake, it may cause excessive loosening or damage to the bearing.

2. To align the screw rod with the center hole of the shaft, pay close attention to the force of the bearing during the pull-out process to avoid damage to the hook and bearing.

3. Pay attention to prevent the hook from slipping off, and the angle of the two feet of the puller should be less than 90°

3. Pushing and disassembling method

This method requires the use of a press to push the bearing, the working process is stable and reliable, and generally does not damage the machine and the bearing. Note that the force point of the press should be on the center of the shaft and cannot be biased. Common presses are manual, mechanical or hydraulic.

4. Heat treatment disassembly method

The bearings used for disassembly of the tight fit can be heat-treated first, and then pulled out with the help of a puller. Generally, the oil heated to about 100 ℃ is poured on the bearing to be disassembled. After the bearing ring is heated and expanded, the bearing is pulled out evenly with the help of a special puller.

When disassembling this method, self-protection and oil recovery should be done to prevent burns; the shaft body should be wrapped before heating to prevent the bearing from being disassembled due to thermal expansion of the shaft body.

slewing bearing manufacturer made in china

Slewing Bearing

Slewing bearing is a kind of large bearing with special structure that can bear large axial load, radial load and overturning moment and other comprehensive loads at the same time.

Under normal circumstances, the slewing ring bearing itself is equipped with mounting holes, lubricating oil and sealing devices, which can meet the different needs of various types of hosts working under various working conditions; on the other hand, the slewing ring bearing itself has a compact structure and can guide the rotation.

With the characteristics of convenience, easy installation and easy maintenance, it is widely used in large-scale rotary devices such as lifting and transportation machinery, excavators, construction machinery, port machinery, wind power generation, medical equipment, radar and missile launchers.

basic structure

A slewing ring bearing is usually composed of four major components: inner ring, outer ring, rolling elements, and spacer blocks. Because the core component adopts slewing bearing, it can bear axial force and radial force at the same time. There are many forms, but the structure and composition are basically the same.

From left and right are (upper part): 1. Outer ring (with or without teeth) 2. Sealing belt 3. Rolling body (ball or roller) 4. Oil filler

From left and right are (lower part): 1. Plug 2. Taper pin 3. Inner ring (with or without teeth) 4. Spacer block or cage 5. Mounting hole (wire hole or smooth hole) slewing bearing Alt.

01 series slewing bearing

The single-row four-point contact ball slewing bearing is composed of four parts: inner ring, outer ring, steel ball and spacer block. radial force. Construction machinery such as rotary conveyor, welding manipulator, small and medium-sized crane and excavator can be selected.

02 series slewing bearing

The double-row ball slewing ring bearing has three races, and the steel balls and spacers can be directly discharged into the upper and lower raceways. According to the stress conditions, two rows of steel balls with different diameters are arranged.

This kind of open assembly is very convenient, and the bearing angle of the upper and lower arc raceways is 90°, which can bear a large axial force and tipping moment. When the radial force is greater than 0.1 times the axial force, the raceway must be specially designed.

The axial and radial dimensions of the double-row reducing ball slewing bearing are relatively large and the structure is tight. It is especially suitable for loading and unloading machinery such as tower cranes and truck cranes that require medium or larger diameters.

Series Slewing Bearings

The single-row cross-roller slewing bearing consists of two races, with compact structure, light weight, high manufacturing precision, small assembly clearance, and high requirements for installation accuracy. Force, tipping moment and larger radial force are widely used in lifting and transportation, construction machinery and military products.

Series Slewing Bearings

Three-row roller slewing bearings have three races with separate upper and lower and radial raceways, so that the load on each row of rollers can be determined exactly. It can bear various loads at the same time, and is the one with the largest bearing capacity among the four products.

The axial and radial dimensions are large and the structure is firm. It is especially suitable for heavy machinery requiring large diameters, such as bucket wheel excavators, wheel Cranes, marine cranes, port cranes, molten steel running table and large tonnage truck cranes and other machinery.

Light Series Slewing Bearings

Lightweight slewing bearing has the same structural form as ordinary slewing bearing, light weight and flexible rotation. Widely used in food machinery, filling machinery, environmental protection machinery and other fields.

HS Series Slewing Bearings

The single-row four-point contact ball slewing bearing is composed of two races, with a compact structure, and the steel ball contacts the arc raceway at four points. Mainly used in truck cranes, tower cranes, excavators, pile drivers, construction vehicles, radar scanning equipment and other machines that are subjected to overturning moment, vertical axial force, and horizontal inclination force.

HJ series slewing bearing

The single-row cross-roller slewing bearing consists of two races, with compact structure, high manufacturing precision, small assembly clearance, and high requirements for installation accuracy. Overturning moment and large radial force are widely used in transportation, construction machinery and military products.

Other series of slewing bearings

■ Single-row four-point contact ball slewing bearings (QU, QW, QN series)

■ Four-point contact slewing bearing (VL series)

■ Four-point contact slewing bearing (VS series)

■ Four-point contact slewing bearing (V series)

■ Single Row Crossed Roller Slewing Bearings (XS Series)

■ Single Row Crossed Roller Slewing Bearings (X Series)

Code composition
Code notation for slewing bearing

The composition of the code

The bearing code consists of the basic code and the rear code.

The composition of the basic code

The basic code is divided into three parts, the front part is the code of the structure type and the transmission type, the middle part is the diameter of the rolling element (for bearings with more than two rows of rolling elements, the maximum rolling element diameter), and the rear part is the diameter of the rolling center of gravity (for two rows of rolling elements) The bearing of the above rolling elements is the diameter of the largest rolling center of gravity)

1. The structural type code shall be in accordance with the rules in Table 1.

01 Four-point contact ball bearing; 02 Double-row reducing ball bearing; 11 Interspersed cylindrical roller bearing; 13 Three-row cylindrical roller bearing.

2. The transmission type code shall be in accordance with the rules in Table 2.

0 toothless type; 1 small module of involute cylindrical gear external teeth; 2 large module of involute cylindrical gear external teeth; 3 small module of involute cylindrical gear internal teeth; 4 involute cylindrical gear The inner teeth have a larger modulus.

3. Basic code compilation rules

When the basic code is arranged, the structure type code and the transmission type code are written consecutively, and the front part, the middle part and the rear part are separated by .

Folding Tolerance Clearance
The tolerances and clearances of the slewing bearings conform to JB/T 10471 “Rolling Bearings – Slewing Bearings”, and the tolerances and clearances of the slewing bearings for wind turbines conform to JB/T 10705 “Rolling Bearings – Wind Turbine Bearings”.

If the customer has other special requirements for size, tolerance and clearance, the corresponding products can be provided according to the operating conditions and user requirements.

folding cage
The cage types used in slewing bearings have different structural types such as integral cage type, segmented cage or isolated cage. The integral cage or segmented cage is made of 20-gauge steel or ZL102 cast aluminum alloy. The isolation cage is made of polyamide 1010 resin, ZL102 cast aluminum alloy or QA110-3-1.5 aluminum bronze. With the continuous development of the material industry, nylon GRPA66.25 has also been popularized and applied in the design of segmented cages.

Applied Materials
Materials for rings and rolling elements

Under normal circumstances, the rolling elements of the slewing bearing are made of carbon-chromium bearing steel which is hardened as a whole. The grade is made of GCr15 or GCr15SiMn steel; the slewing bearing ring is made of surface hardened steel. When the user has no special requirements, it is generally made of 50Mn steel, but sometimes in order to meet the needs of the host in some special applications The specific conditions of use select other grades of surface hardened steel, such as 42CrMo, 5CrMnMo and so on.

material for cage

Cages for slewing bearings have integral, segmented, spacer block and other structural forms. The integral and segmented cages are made of 20-gauge steel or ZL102 cast aluminum alloy. The spacer block type is made of polyamide 1010 resin, ZL102 cast aluminum alloy, etc.

material for sealing ring

The material used for the sealing ring of the slewing bearing is made of oil-resistant rubber or nitrile rubber.

The codes of the ferrule material and the supply status of the blank are as specified in the table. In the table, “T” means that the blank of the ring is supplied in a quenched and tempered state, and “Z” means that the blank of the ring is supplied in a normalized state.

code

Material and blank state

45BT

45BZ

42CrMoT

42CrMoZ

5CrMnMoT

5CrMnMoZ

code

Material and blank state

42SiMnT

42SiMnZ

45MnT

45MnZ

50MnT

50MnZ

The diameter of the center circle of the rolling element is 3150mm, the diameter of the ball is 75mm, the gear modulus is m=20mm, the ring material is 50Mn, and the blank material is the normalized state.

in stock crossed roller slewing bearings

1.Crossed Crossed Roller Slewing Bearings

Crossed cylindrical roller bearing is one kind of bearing whose rollers are square crossing arranged between outer ring and inner ring. The rollers contact the raceway in linearity, so this bearing has better rigidity and less elastic strain. At the same time, this bearing can carry radial load, axial load and moment load simultaneously. They are especially suitable for high rigidity and high running accuracy applications.
The dimension of the inner and outer rings is a minimum to miniaturization, especially extremely thin type is close to the limit of small size, and high rigidity, so it is optimal for applications such as joints and swiveling units of industrial robots, swiveling tables of machining centers, rotary units of manipulators, precision rotary tables, medical instrument, measuring instruments, IC manufacturing machines, and etc..

2.What is a crossed roller slewing bearings

Among the crossed roller slewing bearings, cylindrical rollers are arranged perpendicular to each other through spacers on a V-shaped groove rolling surface at 90 degree, so the crossed roller bearing could bear multi-direction loads, such as radial load, axial load and moment load. Miniaturized inner ring and outer rings’ size, the extremely thin form nearly close to small size. And it has high rigidity, so it very reasonable for joints of industrial robots and rotary parts, rotary of mechanism center, mechanism rotary arm, precision rotary table, medical equipment, calculators, IC manufacturing equipment and other equipment. crossed roller slewing bearing Alt.

Due to perpentical crossed cylindrical rollers has isolation spacers, prevent cylindrical tilt and cylindrical rollers friction, reduced the rotation torque. Othewise, compared with steel plate holder, there will be no edge stress concentration or locking of the rollers. At the same time, inner ring or outer ring is two-part structure, the clearnace of the crossed roller slewing bearings could be adjusted, even if preload is applied, it also could rotate highly precision and steady.

The application of high precision crossed roller slewing bearings

Machine tool : turret indexing、index plate、loader.
Robot : rotation、joint drive parts.
Semi-conductor manufacturing equipment : handling robot、examination platform.
LCD manufacturing equipment: handling robot、inspection platform、photosensitive application roller drive.
Printer : photosensitive application roller drive.

Crossed roller slewing bearings

High precission and capacity to support loads in all directions.

Very specific features to adapt to high precision applications

Renogear cross roller bearings feature high rigidity and high rotational precision. Since it has cylindrical rollers arranged orthogonally, it can support loads in all directions.

This bearing is widely used in rotating parts that require compaction, high rigidity, and precision at rotating.

3.High rotating precision and load crossed roller slewing bearing

Renogear produces cross roller bearings with a very compact structure. The rolling surface has linear contact, so the elastic displacement based on the bearing load is extremely minimal, and furthermore, it is capable of bearing complicated loads in all directions (radial, axial and moment) and at the same time.

Crossed-roller bearings are bearings for high-precision applications whose dimensions conform to ISO dimension series 18 as per DIN 616. They comprise outer rings, inner rings, rolling elements and plastic spacers. The outer ring is split and is held together by three retaining rings.

Due to the X arrangement of the cylindrical rollers, these bearings can support axial forces from both directions as well as radial forces, tilting moment loads and any combination of loads by means of a single bearing position. As a result, designs involving two bearing positions can be reduced to a single bearing position. Crossed roller bearings are very rigid, have high running accuracy and are supplied with normal clearance, low clearance or preload. The bearing outer rings are easily fixed to the adjacent construction using clamping rings.

A slewing bearing or slew[ing] ring (also called a turntable bearing) is a rotational rolling-element bearing that typically supports a heavy but slow-turning or slowly-oscillating loads in combination (axial, radial and moment loads), often a horizontal platform such as a conventional crane, a swing yarder, or the wind-facing platform of a horizontal-axis (yaw) windmill. In other orientations (e.g. a horizontal axis of rotation) they are used in materials handling grapples, forklift attachments, welding turnover jigs and so on.

Compared to a “normal” ball bearing the rings are quite wide and usually have holes drilled in them to provide fixation to a structure. Seals can be provided between the rings to protect the rolling elements. Compared to other rolling-element bearings, slewing bearings are relatively thin section and require that the structure to which they are bolted is stiff enough so that under load predefined limits of distortion are not exceeded.

Slewing rings range in size from as little as 100mm diameter to well over 15 000mm (often segmented at this size for easy transport and handling); for example the bearings on the Falkirk Wheel are 4 meters diameter and fit over a 3.5 meter axle. Slewing bearings are often made with gear teeth integral with the inner or outer race (or both in rare cases) used to drive the platform relative to the base (for example in winches).

Slewing bearing designs range from single row ball or roller style, through double row ball or roller, triple row roller, combined (1 roller/ 1 ball) or wore guided raceways – each design having its own special characteristics and application. Old designs can have split rings to allow tight control on preload during assembly.

As for other bearings that reciprocate, rather than rotating continuously, lubrication can be difficult. The oil wedge built up in a continuously rotating bearing is disrupted by the stop start motion of slewing. Instead, a hydrostatic bearing with pumped oil flow may be used.

china slewing ring bearing suppliers

1.Slewing Ring Bearing Abnormal Noise

For large slewing ring bearings, especially during the installation and operation of newly installed large slewing ring bearings, the sound, abnormal sound, regular, segmented and unknown situations, after eliminating the interference of foreign objects, can be adjusted from the following aspects. In most cases , can be excluded, Luoyang Bearing Yuan Gaogong, 158-9658-0190. Please do not reprint.

Increase the lubricating strength and lubricating interval, all the lubricating holes are fully lubricated, and the test run is about a week. If the effect is not obvious, adjust it from the following aspects:

1. First loosen all the mounting bolts of the slewing ring bearing outer ring;

Next, measure the clearance between the flange and the slewing ring bearing contact surface:

For gaps greater than 0.1, it is recommended to use copper or stainless steel pads to eliminate them;

Then re-tighten all the bolts with the symmetrical cross method;

Finally, try turning it on again:

Turn forward and reverse for three turns each and then listen to the original abnormal noise?

2. If there is still the original abnormal sound after the first step, loosen all the inner ring bolts, and repeat the operation according to the first step.

Note:

The outer ring first, then the inner ring, the order cannot be reversed.

3. Measure the backlash of the large and small gears:

First find the green paint on the outer tooth top of the slewing ring bearing, and measure the backlash value of the big and small gears based on the tooth with the green tooth top;

suggestion:

Controlled by industry experience in:

0.6~0.8mm is better. Modulus 0.03/0.04*Modulus m

4. The method of adding grease:

4.1, it is recommended to close the middle and lower drain oil circuits;

4.2, only add grease to the top row of oil holes;

4.3. Use grease with higher viscosity for filling;

4.4, add grease quantity:

Until a small amount of grease overflows from the top sealing ring.

slewing ring bearing Alt.

2.Slewing ring bearing and pinion meshing

Classification of molybdenum disulfide extreme pressure grease:

Lithium molybdenum disulfide grease is a high temperature grease that can adapt to ordinary loads”);”>conditions

Molybdenum disulfide extreme pressure lithium grease is a high temperature grease under high load “);”> conditions

Molybdenum disulfide extreme pressure lithium complex grease is a high load high temperature grease with synthetic base oil

1. Molybdenum disulfide has good water resistance, good mechanical stability and pressure resistance, and is mainly used for the lubrication of heavy-duty machinery.

2. Molybdenum disulfide has a certain corrosive effect on copper and its alloys. It is not suitable for copper pipes to be transported, which will cause pipeline blockages and cause oil shortage accidents.

3. It is not suitable for worm gear and worm gear made of copper alloy, which will lead to broken teeth due to corrosion.

4. It is not suitable for rolling bearings with copper alloy cages, which will cause the cage to break due to corrosion.

5. When parts made of copper and its alloys need to be lubricated, it is best not to use lubricating products containing molybdenum disulfide.

Ball Slewing Bearing In Stock

Slewing bearing steel ball size and roller size

When choosing a slewing bearing and a slewing bearing, the first factor is the carrying capacity, the load capacity, or in layman’s terms, the load capacity. The size of the load is determined by the diameter and quantity of the rolling element steel balls or balls. In a word, the larger the rolling element, the more the number, the stronger the bearing capacity. Secondly, point contact has stronger load capacity than line contact.

At the beginning of the design, for the calculation of the load capacity, the diameter of the rolling elements should be estimated first. Generally speaking, four-point contact ball bearings, crossed roller bearings, and three-row roller bearings have the following calculation techniques:

Four-point ball bearing steel ball diameter, assembly height × 0.375, and secondly, hole center diameter – hole diameter – 12 – rotation center diameter, compare the two, and choose the smaller value.

The number of pieces is calculated as, the diameter of the center of rotation × π÷ the diameter of the steel ball = the number of pieces

Double row ball bearing × 2 can be.

Crossed roller bearing hole center diameter-diameter-15-rotation center diameter (30 for 2 meters, 50 for 4 meters)

Three-row roller structure bearing, thicker ring height ÷ 5.2, and then select it in combination with the roller group arrangement.

In the design and selection stage, whether it is a precision slewing bearing, a large ladle slewing bearing in a steel mill, a bucket turbine bearing, a high-speed rotating slewing bearing, or a large crane bearing, a crane slewing bearing, and various working conditions For the slewing ring bearing, the working conditions determine everything.

slewing bearing Alt.

Heavy-duty precision large bearings are required, and three-row roller structure bearings are generally selected.

It is necessary to control the precision well, and the precision is not easy to lose. Crossed roller bearings are selected because they are in line contact.

High-speed slewing bearing is required, four-point contact ball bearing is selected, and integral cage, PTFE cage, or copper cage or steel cage is used.

Need precise pointing, precise positioning and stop-and-go, vertical installation, inclined installation, ball bearings are preferred.

When installing, pay attention to the direction of the taper pin, the size of the spigot, the lubrication system and the anti-corrosion effect.

Usually, the slewing bearing can have external teeth and internal teeth, and the tooth shape can be helical, half-tooth, or the tooth surface can be quenched, and the tooth surface can be quenched and tempered. Specially stated in the drawing.

Then, the subject of this article, talk about the gear accuracy grade of the slewing bearing and the feasibility, necessity and practicability of gear grinding.

You should know that the reason why the rotary slewing bearing is used as a rotating mechanism is that it is easy to maintain and maintain, and the other is to use the low-speed and heavy-load characteristics of the slewing bearing. Most equipment cannot obtain high precision, high precision, high speed and high load through the slewing bearing. In other words, the slewing bearing itself, as a precision component, is actually a customized product.

Gear accuracy grades are usually indicated by 10/9/8, and 7/6/5 generally require grinding. The grinding process is to achieve precise meshing and precise pointing and positioning. Most do not need to grind the teeth because of the high cost of grinding them.

Regarding the slewing bearing, it is usually said that there are ordinary products and precision products. There are four grades of P0, P6, P5, and P4. The actual custom high-precision slewing bearing is basically higher than the P4. Ordinary bearings and high-precision slewing bearings, from the standard implementation, the slewing ring bearing is JB/T2300, most of which are rough turning and finishing. The slewing bearing is JB/T10471, most of which are CNC finishing and grinding. The technical indicators of precision slewing bearings are clearly decomposed, and are classified into categories from dimensional tolerance, runout, clearance, gear accuracy and the implementation standards of all components.

In terms of application, slewing bearings are basically stupid and bulky mechanical equipment, such as tower cranes, cranes and mixer trucks.

The precision slewing bearing is also relatively demanding equipment life and reliability requirements.

three-row cylindrical rollers slewing ring bearings made in china

1.Three-row cylindrical rollers slewing ring bearings

Three-row cylindrical rollers slewing ring bearings are the perfect choice for heavy duty bearings. It is also the most stable, reliable and longest life slewing bearing.

The three-row cylindrical roller combined slewing bearing bears axial load, overturning moment and radial load at the same time. Compared with the crossed cylindrical roller slewing bearing, the load of each roller is reduced.

Compared with the double row reducing ball slewing bearing, the point contact is changed to the line contact, which reduces the contact stress. The load carrying capacity is the highest bearing.

The axial load and radial load of the structure are borne by different rollers, wherein the axial load and overturning moment are borne by two sets of rollers with the axis horizontally placed, and the radial load is borne by a set of rollers placed with the axis vertically.

Different raceways and rollers bear, so under the same stress conditions, the diameter of the bearing can be greatly reduced, thus making the host more compact, and it is a slewing bearing with high bearing capacity.

This structural bearing is suitable for occasions with large axial load and overturning moment, large radial load, and low friction torque requirements. Cages are generally made of nylon isolation fast, nylon segmented cages, aluminum alloy cages segmented steel cages and brass cages according to different applications.

three-row cylindrical rollers slewing ring bearings Alt.

Application areas:

Widely used in stacker and reclaimer, overweight transport machinery, port crane, ladle turntable, shield machine and other applications.

The most commonly used structure of slewing bearings, four-point contact ball bearings, including double-row ball bearings, crossed roller bearings, including crossed tapered roller bearings, three-row cylindrical rollers slewing ring bearings, its technical characteristics? What are the technical characteristics, and what kind of bias is there in the selection of working conditions? This article focuses on the discussion.

Generally speaking, four-point contact ball bearings are resistant to permanent fatigue, crossed roller bearings are resistant to permanent deformation, and crossed tapered roller bearings have strong rigidity and high rotational accuracy. The tthree-row cylindrical rollers slewing ring bearings has the same size as the slewing bearing with high load capacity.

Based on this, the characteristics of various structural bearings in the application are obviously different.

What are the characteristics of three-row cylindrical rollers slewing ring bearings? In short, four sentences: 1. The strongest bearing capacity 2. The axial load and eccentric load capacity surpasses other structures, unique 3. The force analysis is obviously optimized 4. The master

But why choose an integral cage? Steel cages and copper cages are the most common. Force analysis and force direction, one is inclined installation, vertical installation and often bear heavy load, to ensure the rolling motion of the ball, the force distribution is even.

In this way, the life and reliability of the bearing are significantly improved after the use of the integral cage. Of course, the cost will increase by at least 30,000 to 100,000 RMB. Compared with safety and reliability, it is still quite worthwhile.

To put it bluntly, the overall cage is to ensure that the rolling elements are in place and operate smoothly and orderly, so that whether it is installed at an inclined angle or installed vertically, it can ensure quality and life.

Three-row cylindrical rollers slewing ring bearings are the ultimate form of construction for low-speed, heavy-duty slewing bearings. In order to ensure the heavy-duty life and reliability of the slewing bearing, the selection of the structural form of the cage is very important. The reference index is the demand of the working condition.

The cage of the three-row roller bearing is usually based on the main thrust roller cage and the auxiliary thrust roller cage, and the radial cage is supplemented by the design idea. There are boxed cages, segmented cages and integral cages. , the cost increases sequentially, and its stability is relatively gradually enhanced.

It should be pointed out that segmented cages and integral cages are more targeted for special working conditions. Boxed cages are only suitable for horizontal installation.

slewing ring manufacturers factory

1.Large heavy-duty ladle slewing ring failure

The ladle slewing bearing is the core component of the ladle casting equipment on the steelmaking production line. It is a large slewing ring. In addition to bearing axial and radial forces, it also bears a large overturning moment during use.

It has large size and low rotational speed (1 ~ 10 t/min), large load, high cost, and difficult maintenance, the design life is generally 8 to 10 years, and its use conditions and life factors directly affect the connection between steelmaking and continuous casting processes.

In the process of use, the actual service life of this type of bearing varies greatly due to different manufacturing levels and working conditions. Taking a large iron and steel group as an example, the actual service life of the ladle slewing bearing of the continuous casting machine with a design life of 8 years is only 4 years at the lowest and 17 years at the longest, showing a large dispersion.

Since there are generally no spare parts for this type of slewing ring, if a failure occurs, it will cause huge downtime losses, so it is very important to predict the operating state of this type of slewing ring. Through the manufacturing and application experience and the successful experience (-4) in the fault diagnosis of rolling bearing, the wear state of the large and heavy-duty ladle slewing bearing was accurately grasped, and good application results were obtained.
All in all: In the early stage, the large bearing of the ladle appeared to have noise, vibration, clearance and unknown debris. Basically, new bearings should be prepared for replacement at any time within 3 to 6 months.
At the same time, there is a new design of quality documents and drawings for the design, improvement and improvement of the new bearing to ensure that the large ladle bearing can be more stable, reliable and durable.

slewing ring Alt.

2.Axial clearance Radial clearance for slewing ring

The determination of axial clearance, radial clearance and inclined clearance and the influence on the slewing ring, in layman’s terms, is the artificial regulation of the bearing clearance, according to the size of the size, the influence of the structure and the setting of the working conditions. In essence, the size of the clearance has no absolute relationship with the quality and stability of the bearing. As a set value in the process, it is only a technical index to measure the bearing.

The clearance of four-point contact ball bearings, crossed roller bearings and three-row ball bearings is directly related to the diameter of the slewing ring. The larger the diameter, the greater the clearance. The function of the clearance is to adjust the rotational flexibility of the bearing. . Too large is easy to wear, too small hinders rotation. The clearance of precision bearings is set according to the requirements of the working conditions.

Measurement of axial clearance The determination of radial clearance and inclined clearance is mainly based on the dial indicator, watch frame, jack, and the average value of three degrees. There is only one degree in the radial direction, and the maximum value of three points is determined. , the inclined clearance mainly investigates the maximum value of a single point and one side.

First of all, it needs to be clear that whether the standard implemented by the slewing bearing is JB/T10471 or the JB/T2300 implemented by the slewing bearing, in fact, to sum up, most of the application occasions of the slewing bearing belong to the heavy field of the heavy industry. Sexual requirements are not high, generally speaking, they are all grade 10 teeth. As for the quenching of the tooth surface, the accuracy level is lost to level 12. From the perspective of the application, it does not affect the meshing. Therefore, emphasizing the high precision of the gear is a fuss and nitpicking. .

Of course, the accuracy of the slewing bearing is generally obtained by grinding the teeth. Several key data of measuring gear are as follows,

Common normal length, common normal deviation, tooth jump, fixed chord tooth height and tooth thickness, as for tooth shape, tooth direction and tooth pitch, you need to use professional instruments to measure.

Regarding gear accuracy measurement, we can currently measure items such as common normal dimensional tolerance, common normal variation deviation, fixed chord tooth height and tooth thickness. For other gear accuracy requirements, such as tooth shape, tooth direction, tooth pitch, etc., currently unconditional measurement. In the case of grinding teeth, it is generally within a reasonable range.

slewing ring bearing for sale

1.Advantages of slewing ring bearing grinding

The advantages of slewing ring bearing grinding: reduce meshing impact, vibration and noise and wear, improve meshing accuracy, transmit torque smoothly, improve life, and reduce accumulated errors.

Four Requirements for Gear Transmission Accuracy

1. The accuracy of the transmission movement. It is required that the angle error of the gear in one revolution is limited within a certain range, so that the change of the transmission ratio of the gear pair is small, so as to ensure the accurate transmission movement.

2. The stability of the transmission movement. It is required that the angle error within the range of one tooth of the gear is limited within a certain range, so that the change of the instantaneous transmission ratio of the gear pair is small, so as to ensure the stability of the transmission and reduce vibration, impact and noise.

3. The uniformity of load distribution. It is required that the working tooth surfaces in the transmission have good contact to ensure uniform load distribution, otherwise it will cause stress concentration on the tooth surface, premature wear and reduce service life.

4. The rationality of the transmission backlash. It is required to leave a certain backlash between the non-working tooth surfaces of the meshing gear teeth in order to store the lubricating oil, compensate for elastic deformation and thermal deformation and the manufacturing and installation errors of the gear.

slewing ring bearing Alt.

2.The role of spacers and cages for slewing ring bearings

The spacer and cage of the slewing ring bearing and the slewing bearing are expressed as spacer and CAGE in English. Their main functions can be summed up in a word, reducing friction, coordinating the operation efficiency, distributing the load, and guiding the circumferential trajectory of the rolling elements. It is an integral part of the overall design of the bearing.

Cage (that is, bearing cage, also known as bearing cage, foreign name: cage), refers to the bearing parts that partially wrap all or part of the rolling body and move with it, to isolate the rolling body, and usually guide the rolling body and keep it in the bearing.

2 Main functions 1. Keep a proper distance between the rolling elements to prevent the rolling elements from contacting each other to reduce friction; 2. Make the rolling elements evenly distributed, so that the load is evenly distributed;

3. Guide the rolling elements in the no-load area to improve the bearing rolling condition to prevent damaging slippage. The cage must withstand the stress caused by friction, strain and inertial force, and also withstand the chemical corrosion of lubricants, additives in lubricants or substances generated by their aging, organic solvents or coolants. Therefore, the design and material of the cage are extremely important for its performance and the reliability of the bearing.

3 types of cages Bearing cages are divided into stamping cages (Figure 1), solid cages (Figure 2) and strut cages 1. The advantages of stamping cages are light weight and large internal space, which can facilitate the entry of lubricants ; 2. The solid cage is usually allowed to have a higher speed. When the bearing has other forms of motion other than rotation at the same time, especially in the case of high speed, the machined metal cage should also be used;

3. The pillar cage is penetrated by pins Roller with perforations to secure both ends of the pin to the washer. This cage is lighter in weight and can accommodate more rollers and is only used in oversized roller bearings.

4. Cage materials Cage materials mainly include stamping steel, machined steel, stamped brass, machined brass, polymeric materials, etc. Stamped steel cages have high strength and can be surface treated to reduce friction and wear; machined steel cages are generally used for oversized bearings or where brass cages are not suitable; stamped brass cages are used in part Small bearings;

Machined brass cages are generally not affected by bearing lubricants and can be cleaned with ordinary lubricants. Brass cages should not be used for operating temperatures above 250; Polymeric material (nylon 66, nylon 46, etc.) cages Compared with metal cages, it has many advantages such as good toughness, friction and wear resistance, impact resistance, acid resistance and corrosion resistance.

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