Wheel bearings

Related hot search term: wheel Full complement cylindrical roller bearing applications four-point contact ball bearing turntable turntable double volleyball
1. unloader

Unloader turntable bearings with external teeth usually three-row roller structure, approximately four meters in diameter.

2. Crane

Tower crane wheel bearings are usually used in a small four-point contact ball bearing turntable turntable or dual volleyball, no more than two meters in diameter.

3. radar antenna

Shortwave antenna generally with three-row roller bearing turntable substructure, slow rotation.

4. TBM

Shield machine with turntable bearing diameters from 2.5 m to 6 m range, and some larger diameter, these bearings work under very harsh conditions, carrying a large load bearing, corrosion resistance, short life.

5. Ladle turret

Ladle turret truck mounted crane bearing usually with three rows of roller structure, due to work under harsh conditions with dust and high temperature conditions, and on the cage, grease and seals have very high demands.

Engineering Machinery

Wheel bearings engineering machinery usually in a small four-point contact ball bearing turntable, no more than two meters in diameter.

Wheel bearing applications in various fields

Related hot search term: wheel bearing applications four-point contact ball slewing Tri-row roller gear wheel ferris wheel bearing

1. Wind Turbines

Connecting portion yaw bearing mounted on a tower and the cockpit, the pitch bearing mounted on the hub is connected with the root portion of each blade. Each wind turbine with a yaw bearings and three pitch bearings. Yaw, pitch bearing rings of material selection 42CrMo, heat treatment with the overall quenching, raceway surface hardening. Yaw, pitch bearing force situation is complex, and to withstand shock and vibration is relatively large, and therefore, requires both bearings to withstand the impact, but also bear a greater load. Wind turbines host life requirements of 20 years, a larger thrust roller bearing installation costs, thus requiring yaw, pitch bearing life have reached 20 years. Bearing rings matrix hardness is 240-280HB, able to withstand impact without plastic deformation, while the raceway surface quenching hardness 55-62HRC, contact fatigue life can be increased, thus ensuring long life bearing requirements.

2. Ship Cranes

Ship Cranes general use double Reducing ball, four-point contact ball bearing turntable Tri-row roller tooth structure, depending on the carrying capacity, three-row roller slewing bearings are usually used for heavy-duty cranes, wheel and four-point contact ball Reducing double ball bearing turntable for lightweight cranes.

Because the crane operates in -20 ° C- + 45 ° C environment, the higher kind of bearing on the mechanical properties of the material requirements.

3. Offshore Cranes

Depending on the load capacity requirements, offshore crane usually using four-point contact ball slewing and three-row roller gear wheel bearings.

Applications in offshore crane turntable bearings with special material requirements, the mechanical properties of the material to be able to guarantee the safety factor under extreme load, forgings sampling Charpy impact test can reach the average of 42 J @ -20 ° C or 27J @ - 40 ° C. Bearing finished CCS to be certified.

4. harbor mobile cranes

4 m harbor cranes usually using tooth or teeth outside diameter of three-row roller slewing bearings to withstand high overturning moment.

5. Stacker Reclaimer

Reclaimer with column wheel bearings usually ball joint, three-row roller-type and cross roller type, most ultra-three meters in diameter. Due to poor working conditions, dusty, these slewing ring bearings have a high load carrying capacity, long life, good sealing performance characteristics.

6. Ferris wheel

For four-point contact ball bearing turntable Ferris wheel on the outside diameter of 4100mm, thickness 85mm.

The introduction of slewing ring

Wheel bearings, slewing ring, also known, is a way to withstand large axial load, radial load and overturning moment of large self aligning ball bearings  Wheel bearings are generally with the mounting holes in the gear or external gear, lubrication holes and sealing devices, which enable the host compact design guide reliable, and easy maintenance.
     Wheel bearings with or without gear, external gear teeth and inside the four-point contact ball bearings, double row angular contact ball bearings, cylindrical roller bearings cross, cross tapered roller bearings and three-row cylindrical roller bearings and other kind of structure types. Where the four-point contact ball bearings with high static load capacity; Cross cylindrical roller bearings with high dynamic load capacity; cross tapered roller bearings make through preloaded bearings with a larger supporting rigidity and high rotation accuracy.
     Wheel bearings are widely used on lifting machinery, mining machinery, construction machinery, port machinery, shipbuilding, machinery and mechanical precision radar and missile launchers and other large rotary device.
Depending on the turntable bearing structure type structure can be broadly divided into the following types:
A four-point contact ball bearing turntable
2, double four-point contact ball bearing turntable
3. Cross cylindrical roller wheel bearings
4. Cross tapered roller wheel bearings
5, three-row cylindrical roller bearing turntable

Large thin wall bearing outer quenching and tempering technology breakthrough

From March last year, the project, which lasted more than six months improved, to large-scale promotion this year, the company single-row crossed roller slewing bearing a large thin-walled bearing outer quenching and tempering process improvements achieved a breakthrough: reducing distortion, reduce scrap rates, removal of all seized and subsequent shaping, to the stress process, saving time and labor costs, economic benefits are considerable.
As soon as possible in order to break this bottleneck, last March, the company has set up a project team bearing the main research content is the medium and large thin-walled bearing outer heat deformation control. First, in the application of the device, the project team proposed to replace the new roller furnace mesh belt furnace. Because the former use of radiation heating, the temperature can be precisely controlled, better heating uniformity, can greatly reduce the amount of deformation. Meanwhile, the roller furnace with nitrogen and propane as a protective atmosphere that allows oxidation products through appropriate to achieve the desired hardness, to meet different customer requirements.
The new production line roller furnace into operation after a period of time, the question came up: the workpiece into the furnace to be of special baskets, large deformation proportion remains high specification products. The project team developed a project implementation plan, schedule lists: the first phase of small batch processing, such as the promotion of a wide range of process maturity and then, at the same time according to the time schedule, to reduce the amount of deformation also made clear the indicator. Through several experiments, on the one hand, optimized display mode, eventually completely without baskets directly to the workpiece placed on the stove, so a single volume into the furnace to increase production efficiency also will increase; on the other hand, the project team By replacing the quenching oil, in accordance with the product model to set the stirrer speed and time, so that the quenching oil is more evenly distributed in the surface, can be achieved to ensure the hardness after quenching and qualification requirements of the microstructure, in order to better control the amount of deformation . After these improvements reflect subsequent grinding staff is very good. They say that good quality new processing technology, especially small sag, the rejection rate is almost zero.
Bearing outer ring after quenching and tempering after heat treatment, can improve product strength, hardness, wear resistance, fatigue strength and toughness. Previously, the company slewing ring bearings technology equipment used mesh belt furnace and furnace roller quenching, tempering, there is always some distortion problems affecting the efficiency quality. Especially greater than 150 mm in outer diameter of the large product, the deformation is more pronounced. In recent years, bearing the company's market has been expanding from the traditional automotive industry market more towards wind power bearings, machine tool bearings and other emerging industries range, product specifications growing, medium and large bearing outer ring more and more . How to solve the problem of a product deformation caused by the traditional process, the company has become an urgent need to address the "big obstacle."
Because deformation meet the requirements, the vast majority of medium and large companies are now bearing products do not need a full inspection, plus reduce the stress to both shaping and procedures, in the same middle class, the product circulation accelerated greatly improved production efficiency. Furthermore, the bearing outer ring taper becomes smaller, the subsequent grinding allowance is also reduced. In terms of cost, plastic, five employees to streamline the inspection process, at least an annual payroll savings of 200,000 yuan; the same time, to reduce stress and subsequent shaping of the original annual electricity use of 40,000 yuan, the benefits of these savings are very impressive .
After six months of exploration and constantly try to verify quenched by the end of last year, bearing the company double row ball slewing bearing a large amount of deformation of thin-walled outer ring has basically met the technical criteria deformation proportion dropped to 80% more than before.
Today, the company is working to transform the original roller furnace, so that you can promote the use of new technology as soon as possible. Heat treatment unit plan.

Design features and classification of thin wall bearing

High precision thin section bearing  very quiet and strong carrying capacity. These ball bearings, there are three design, and extremely small, most of the cross-section is square. In these series, even larger shaft diameters and bearing bore, the cross-section remains unchanged. These bearings are therefore called constant section. It is this characteristic of the standard iso series with the thin-walled rings bearing conventional bearing distinguished. Therefore, a larger cross-section can be selected using a stronger bearing carrying capacity without changing the shaft diameter. Thin wall bearing rings can be designed to require very little space is extremely light and bearings.
Thin wall bearing rings can be deep groove ball bearings, four point contact bearings, thin section angular contact bearings  In different series are provided over a variety of designs. Series depends on the cross-sectional size. Match ball with the series.
Deep groove ball bearings can support bi-directional axial load and radial load.
Four point contact bearings can support axial loads in both directions as well as radial loads; therefore they are in contact with the double row angular ball bearings running the same way.
Angular contact ball bearings can match the optimal number of balls and the contact angle of 30 °. They support radial loads than deep groove ball bearings or four point contact bearing higher, and can support axial loads from the same direction. For special needs, angular contact ball bearings are also available as matched bearings provide. Therefore, these combinations of stiffness and load capacity than a single bearing products to be much higher.

The reason of aligning ball bearing failure analysis

aligning ball spherical ball bearings cause of failure is often multifactorial, all design and
manufacturing process and the impact of factors related to failure of the bearing, it is not easy to judge the analysis. Under normal circumstances, in general, can be considered and analyzed both from the use of factors and internal factors.
Use the adjustment factor mainly refers to the installation, use and maintenance, repair and other maintenance meets the technical requirements. Installation conditions is one of the primary factors in the use of the factors bearing is often caused due to improper installation package bearing the stress state changes between the various parts, aligning ball bearing in a normal state of operation and early failure. According to the spherical plain bearings installation, use, maintenance, maintenance of the technical requirements for operation of
the bearing to withstand load, speed, temperature, vibration, noise and lubrication condition monitoring and inspection, abnormal immediately find reasons to adjust to return to normal. In addition, the quality of the grease and the surrounding medium, and the atmosphere is also important for analysis testing.
Internal factors mainly refers to the design, manufacturing process and material quality three factors determine the quality of the bearing.
First, along with a reasonable structure design has advanced, will have a longer bearing life. Manufacture of bearings generally through forging, heat treatment, turning, grinding and assembly of multi-channel processing. The reasonableness of the processing technology, advanced, will also affect the stability of the bearing life. Which affect the quality of the finished product bearing heat treatment and grinding processes, tend to have a more direct relationship with the failure of the bearing. Recent studies on the bearing surface metamorphic layer show that the grinding process is closely related to the bearing surface
quality.
Metallurgical quality aligning ball four point contact ball slewing bearing material was the main factor affecting the early Rolling failure. As metallurgical techniques (such as bearing steel vacuum degassing, etc.) advances, improved quality of raw materials. Raw material quality factors in bearing failure analysis in the proportion has decreased significantly, but it is still one of the main factors bearing failure. The adequacy of the selection is still bearing failure analysis of factors must be considered.
The main task of aligning ball bearing failure analysis is based on a lot of background material, analysis of data and failure modes, failure to identify the main factors causing the bearing to make targeted improvements to extend bearing service period, to avoid bearing occurrence of unexpected early failure.

Comprehensive analysis of angular contact ball bearings

Angular contact ball bearings, which is commonly referred to as angular contact ball bearings, which allow the operating speed and deep groove ball bearings are similar, but support more rigid than the deep groove ball bearings, mainly because of the bearing can be loaded more of the ball, the radial load carrying capacity than ordinary ball angular contact bearing large, but also to withstand large axial load or bear pure axial load. These bearings are generally used in pairs for small span rigid support shaft or double precision spindle, can improve the rigidity of the bearing system.
Structural features of angular contact ball bearings Bearing this structure can withstand the radial and axial loads in one direction. Ball with inner, outer ring 15 °, contact angle 25 °, 30 ° or 40 ° of. The contact angle, the greater the axial load carrying capacity. Under normal circumstances, the two single row angular contact ball bearings opposed, adjusted internal clearance to use.
The two radial bearings, combined bearings pairs called pairs of double bearings. Often, by the same pairs of double-bearing angular contact ball bearings or the same combination of tapered roller bearings.
Double pairs of species, there is a positive paired with outer front double, double pairs parallel with the back of the back pairs of double, and in the same direction.
df and db-shaped form pairs of double bearing, can bear radial load and axial load in two directions, dt shape the direction of the axial load for a big occasion.
Double row angular contact ball bearings contact ball bearing outer ring on the back of two separate angles coincide, the inner and outer rings are each integrated structure. Therefore, the import of this structure bearing, thrust load capacity having two directions.
1, a = 15o angular contact ball bearing 2, a = 25o angular contact ball bearings 3, a = 40o angular contact ball bearings 4, a = 15o-speed sealed angular contact ball bearings 5, a = 25o of high speed seals angular contact ball bearings 6, a = 15o-speed sealed angular contact ceramic ball bearings 7, a = 25o-speed sealed angular contact ceramic ball bearings 8, back to back pairs of angular contact ball bearings [70000c / db type]
9, face by face pairs of angular contact ball bearings [70000c / df type]
10, the series pairs of angular contact ball bearings [70000c / dt type]
11 ball gap double row angular contact ball bearings 12, No ball gap double row angular contact ball bearings 13, one side with a double row angular contact ball bearings 14 dust cover, dust cover both sides with double 15 row angular contact ball bearings, double row angular contact ball bearings with a ring 16 side, the main purpose row angular contact ball both sides with a double row angular contact ball bearing ring angular contact ball bearings slewing ring bearing: machine tool spindles, high-frequency motors, gas turbines, centrifuges, small car front wheel, the differential pinion shaft.
Double row angular contact ball bearings: pump, blower, air compressor, various types of transmission, fuel injection pump, printing machinery.

India's large demand for construction machinery will give an opportunity to the Chinese market

In recent years, with the gradual slowdown in the pace of economic development in China, the development of construction thrust roller bearing machinery industry has entered a more difficult course, but we look to look to neighboring countries, with a large number of infrastructure projects undertaken to increase their demand for construction machinery and equipment, and our good performance engineering machinery products and cost-effective, as they are the best choice, which for China's construction machinery enterprises, is undoubtedly a better market is another.

It is understood that in the next five years, India will be focused mainly on the infrastructure piece, as the major driving force to accelerate the transformation of the economy, continued growth in the face of India's upcoming future infrastructure projects, which brought a huge market for construction machinery in India opportunities, but subject to various factors and constraints, the current development of construction machinery manufacturing industry in India is also relatively weak.

It is understood that, in India, the local purchase of construction machinery should be at least two years to properly put to use, while in China's construction machinery purchased only need six months to properly put into use, by contrast, China's construction machinery and equipment and Compared to India, more competitive and better able to meet with a large number of Indian construction machinery market demand.
Has experienced five consecutive years of 30% of the market growth, the Indian machine tool industry is facing a sharp decline in demand caused by customer demand declined. Despite such challenges, machine production in India is still basically the same as in previous years to maintain growth, including 86% of the contribution from the metal cutting machine tools, metal forming machine tools rest.

Faced with the global economic downturn, the Government of India in order to restore and maintain the momentum of industrial growth has also taken a series of positive responses.

CNC machine tools in India occupies about 65 percent of all sales in the machine. Throughout the slim ball bearing industry, lathes, machining centers, special machines, presses and grinders accounted for 80% of India's total 2008 production of machine tools, manufacturing evolving pushed to the status of India's ninth largest machine tool consumer market. Promote the growth of new industries demand for large machine tools, leading to increased imports. Speaking on metal processing machines, imported products accounted for 75% of India's domestic market share throughout. From the macroeconomic point of view, in April 2008 to March 2009 global economic downturn in the year, India's economy is smooth, and its gross domestic product growth of more than 5%. In the previous three years, India's GDP has maintained a continuous growth of more than 9% of the situation, making it the world's second-fastest economic growth in the country.

From the competitiveness of the industry itself, the Indian machine tool has the following characteristics: India and abroad promising users the ability to provide high-performance machine tools; efforts into high productivity, high efficiency, more cost competitive industry; attaches great importance to the quality of ; to establish close relationships with suppliers and integration of secondary suppliers; actively with the automotive industry, the defense industry and other customers to communicate.