Slewing drive project by LDB Bearings was officially launched

Slewing drive project by LDB Bearings was officially launched

On the afternoon of July 8, 2022, slewing drive project jointly developed by LDB Bearings and a famous European company was officially launched, and the company held a mobilization meeting. At the meeting, the chairman of LDB Bearings requested that the team leaders and backbones of the production workshop must unify their thinking, overcome difficulties, and strictly follow the process and technical requirements to complete the research and development tasks of the rotary drive samples accurately.



At the meeting, Tong Yongzhong, chairman of LDB Bearings, said: “this is the second cooperation between the company and customers. 10 sets of slewing drive samples developed and produced for customers last year have all been accepted after trial by customers, and customers are very satisfied. And then, seven sample orders of slewing drive models were placed in three batches this year.




Finally, Director Zhang of the production department of the company said: “All the staff of the production department will complete this slewing drive production task with the fullest enthusiasm, the most vigorous fighting spirit, the most hard-working spirit, the most tenacious perseverance, and the most perfect products.





The corporate philosophy of “Elaborate Manufacturing, Serve the World” is not only a slogan, but also needs to be implemented in practical work, and also needs all LDB people to challenge themselves constantly. Only in this way, LDB Bearing‘s corporate vision of “committed to becoming a world-renowned slewing drive manufacturer” can be realized. For this reason, LDB people will continue to pursue it unremittingly!

Slewing Bearing Processing Manufacturer

Slewing bearing rolling element

The rolling elements of the slewing ring are made of anti-friction bearing steel. Such materials will be produced according to the company’s standard regulations, and through strict chemical composition analysis of the materials, relevant reports will be printed out. In order to ensure the same quality, the production standard batches will be strictly monitored during the licensing process. LDB slewing bearing rolling body is regularly audited and inspected to ensure the high quality pass rate of the product.

Slewing Ring Washer/Cage

The gaskets and cages of the slewing bearing are mostly made of polyamide. Such a cage can maintain the equidistant rotation of each rolling element during the rotation of the rolling elements, preventing the rolling elements from running safely and reliably. Polyamide gasket cages produced by LDB slewing bearings are of consistently high quality. In certain bearings, metal spacers and cages are also used.

Slewing ring raceway

For the slewing bearing raceway of rolling elements, LDB relies on precise machining and unique engineering principles to keep the rolling elements stable in motion.

Manufacturing process of LDB slewing bearing raceway – car pin

The runway after turning is quenched on a re-quenching machine to increase the hardness of the runway, and the slewing bearing runway after quenching is polished to a certain smoothness.

Slewing Ring Seals

When designing the raceway system of LDB’s large slewing bearing, lip seal kits are designed on both the upper and lower sides. These seals have two main functions: 1. Prevent dust, moisture and other particles from entering the bearing and cause wear and damage; 2. The seals separate the raceway and the bearing ring.

Slewing ring seals are available in a variety of materials and types. The type and material of the seal depends on the shape of the bearing and the surrounding service environment. The slewing bearing of mechanical engineering adopts a simple lip design, which has a better sealing effect. In special circumstances, however, different groove designs are used. The slewing bearing working in a particle-rich environment, with a simple design, is ineffective, and it is easy for grease to flow out of the seal, affecting the slewing bearing operation, and there will be a certain degree of wear. For example, working in ultraviolet and high oxygen content environments will be affected. Therefore, the seals of LDB slewing bearings will be made of different materials according to customer needs, and it is recommended to use specially designed seals, and during the installation process, the seals should be filled with grease.

Slewing Bearing Gear Drive

LDB slewing bearings can have two types of internal gears and external gears, both of which are spur gear operation modes. As well as special gear structures, helical gears and turbine gears, toothless slewing bearings can also be produced according to customer requirements.

Gear hardening

For the most part, the teeth are in their natural state, as are the rings themselves. The strength characteristics of the gear teeth are the strength characteristics of the base metal. If the application requires additional strength and wear resistance, the gear teeth are induction hardened. Hardening of the teeth will increase the wear and strength properties to the desired level. Depending on the pitch diameter and module of the gear, the teeth are induction hardened or rotationally hardened. To avoid metallurgical gaps with unhardened material in the transition zone, the teeth are hardened primarily at the root of each tooth. In addition to improving the load-carrying capacity of the tooth surface, it also increases the strength at the tooth root. Tooth spacing hardened hardened microsections.

Bearing Ring

A bearing ring is an annular part of a radial rolling bearing with one or several raceways.

Bearing rings are divided into: bearing inner ring, bearing ring with raceway on the outer surface; bearing outer ring, bearing ring on the inner surface of the raceway; tapered inner ring, inner ring of tapered roller bearings; tapered outer ring, tapered outer ring outer ring of roller bearings; double raceway tapered inner ring, double raceway tapered roller bearing inner ring; double raceway tapered outer ring, double raceway tapered roller bearing outer ring; wide inner ring, in A bearing inner ring widened at one or both ends to improve the guidance of the shaft in its bore or to provide additional locations for mounting fasteners or seals; a keyed inner ring, a grooved ball bearing inner ring with all or part of the shoulder removed ; Locked outer ring, a grooved ball bearing outer ring with all or part of the shoulder removed; Stamped outer ring, stamped from a thin sheet metal, sealed at one end (sealed stamped outer ring) or open at both ends, generally directed toward the center roll Outer ring of needle bearings; flanged outer ring, bearing outer ring with flanges; self-aligning outer ring, outer ring with spherical outer surface to accommodate permanent angular displacement between its axis line and the bearing seat axis line ; Self-aligning outer race, used for aligning the ring between the outer ring and the seat hole, has a spherical inner surface that matches the spherical outer surface of the outer ring; outer spherical surface, the outer surface of the bearing outer ring is a part of the spherical surface; The front rib of the conical outer ring, the rib on the front of the raceway of the conical outer ring, is used to guide the roller and bear the thrust of the large end face of the roller; the middle retaining ring, the bearing ring with double raceway, such as the double raceway cone The middle integral rib of the inner ring.

Production steps of bearing rings

  1. Bearing ring forging: If over-burning, overheating, and internal cracking into reticulated carbides occur during the forging process, the toughness and strength of the ring will be reduced. Therefore, it is necessary to strictly control the processing temperature, cyclic heating and post-forging heat dissipation conditions (such as spray cooling), etc., especially after the final forging of larger varieties of ferrules, the temperature is above 700 ℃, and they should not be stacked and placed.
  2. Heat treatment of bearing rings: Close monitoring of heat treatment equipment is an important work in the workshop. Monitoring equipment reliability. Important temperature control equipment such as instruments and thermocouples must be closely monitored to ensure accurate and reliable measurement data; those with errors exceeding the standard should be replaced in time, and it is strictly forbidden to operate with illness.
  3. Monitoring of bearing ring grinding process. The finished imported bearing rings are not allowed to have grinding burns and grinding cracks, especially the matching surface of the inner ring screwdriver must not have burns. If the ferrules are pickled, they should be fully inspected, and the burnt products should be removed. Those with severe burns that cannot be repaired or those that fail to be repaired should be scrapped. The ferrules with grinding burns are not allowed to enter the assembly process.
  4. Bearing ring identification management, after the steel is put into storage and before the ring grinding, each process must be strictly managed, and strictly distinguish between GCR15 and GCR15SIMN two different materials and products.

Depending on the application and purpose of the LDB large diameter bearing, different materials are used for the bearing rings. These standards are made of tempered alloy steel and are specified by our own company standard (LN), derived from DIN EN 10083-1. For applications requiring additional properties, special materials such as chrome-nickel steel for low temperature environments are used.

The chemical composition, the handling of the material during the formation of the raw material and the mechanical properties of the base material are specified in the company standards. To ensure consistent quality, each raw material is monitored during manufacturing according to the testing criteria defined in the LDB standard.

Regular audits of suppliers ensure compliance with delivery specifications.

Various certificates are available for raw materials according to DIN EN 10204, as required by the scope of testing and documentation.

On request, provide all documentation required for component or system certification or classification.

Wind Power Bearing Manufacturer

Wind power bearing manufacturer | LDB

In addition to innovative solutions for pitch and yaw bearings, the main focus is on the development of main bearings. LDB wind turbine bearings play a crucial role in its role as a global market leader in slewing bearings. Intensive research and development has led to the successful deployment of LDB wind turbine bearing products in wind power plants (onshore and offshore) around the world.

The Wind drive

Limited resources and rising energy prices pose global challenges. At LDB wind turbine bearings, we are addressing this challenge by developing groundbreaking solutions.

In order to make progress in providing environmentally friendly energy, we are installing increasingly efficient wind power plants around the world, which are now able to compete with fossil energy resources. LDB wind turbine bearings are a strong and progressive partner in the field of onshore and offshore systems. We constantly seek innovation and breakthroughs, so that our customers can not only become part of the new energy era, but also promote the development of the new energy era, and make important contributions to ensuring a more environmentally friendly future.

Carbon dioxide free (CO2) energy obtained through wind power generation is becoming more and more important.Since the establishment of the industry, the company’s commitment to renewable energy has made it a reliable partner for all major wind power plant manufacturers.

Slewing Bearing Installation Surface

Mechanical machining of the bearing connection surfaces on the connecting structure is required . The mounting position of slewing bearings must correspond to that shown in the drawing. If a transporting cross was delivered, it has to be removed before installation.

The corrosion protection can be removed with an alkaline cleaner. Cleaner must be prevented from coming into contact with the seals or the raceway. Remove the protective coating from the upper and the lower mounting surfaces of the slewing bearing as well as from the gear.

The corrosion protection can easily be removed, for example, using a biodegradable alkaline cleaner.

Rapid removal of the corrosion protection and low environmental impact.

The unhardened zone between the beginning and the end of the hardened region of the raceway is marked with an “S” on the inner or outer diameter of each bearing ring. On the gear ring, the hardness gap is marked on the axial surface. Wherever possible, the hardness gap “S” must be positioned outside the main load-carrying areas. If the main working area for the application is known, then the hardness gap of the ring loaded on the circum-ference must also be positioned outside the main load-carrying area.

The bearing must be completely screwed on for commissionings and test runs. Sufficient load / moment loan must be applied to avoid a slip-stick effect on the anti-friction bearing bodies.


Entanglement hazard due to exposed gear

  • Keep hands away from moving parts

The backlash is adjusted relative to the three gear teeth marked in green and should be 0.03 – 0.04 x module.After the final tightening of the bearing,the backlash should be rechecked over the entire circumference. A tip edge radius and a tip relief must be provided on the pinion.

Slewing Bearing Installation&Storage

Slewing Bearing Installation

LDB Slewing Bearing offers an extensive slewing bearing service

Slewing Bearing InstallationTransport and handling

Danger of life by overhead load

  • Do NOT step underneath the load
  • Use suitable slings
  • Use suitable lifting devices
  • Suitable transport tap hole are stated in the bearing drawing

Slewing bearings, like any other part of a machine, require careful handling. They should always be ransported and stored in horizontal position. For safe handling of bearings which include transport holes, high tensile lifting eye bolts must be used. In special cases an internal cross bracing (transporting cross) is required. The bearing weight must be indicated on the crate or pallet. Impact loads, particularly in a radial direction, must be avoided.

Slewing bearings Delivery condition

  • Raceway system

The slewing bearings are delivered filled with one of the greases unless no special lubricant and special grease quantities are required.

  • External contours

The external contours of the bearings (except for holes) have Cortec VCI corrosion protection applied.

  • Gearing

The gearing is not greased. The corrosion protection is applied as for the external contours.

Slewing Bearings Storage

Sensitive surface

  • Do not open the packing with a sharp blade
  • Surface may be damaged

Approx. 6 months in roofed storage areas. Approx. 12 months in enclosed, temperature-controlled areas (temperature > 12 °C ). Outside storage is not allowed.

If required, other corrosion protection agents and types of packaging can be used, e.g. long-term packaging for up to 5 years.

Longer storage periods will necessitate special preservation. After the slewing bearing has been stored for a relatively long time, an increased frictional torque may be observed caused by the suction adhesion of the sealing lip. Careful lifting of the sealing lip with a blunt object around the entire circumference and several clockwise and counterclockwise rotations of the slewing bearing through 360 degrees will reduce the frictional torque to normal.

Slewing bearings Installation

Risk of skin irritation caused by preservative

  • Safety gloves must be worn for removal
  • Pay attention to the producer’s data

Entrapment hazard when putting the load down

  • Location control before putting tazhe load down
  • Mind the staff

A flat mounting surface free of grease and oil is essential for the upper and lower ring to seat firmly. Welding beads, burrs, excessive paint and other irregularities must be removed prior to installation. The bearing rings must be completely supported by the connecting structure.

LDB Slewing bearings  recommends conducting a check on the mounting surfaces with a leveling instrument or laser equipment (this service can be provided by LDB). The flatness values should not exceed the values shown in table 1. To avoid larger deviations and the occurrence of peaks in smaller sectors, any deviation in the range of 0°–180° may only rise evenly once and fall again.

Ball Bearing Manufacturer

Ball Bearing Manufacturer

Ball bearing is a kind of bearing, which places spherical steel balls between the inner steel ring and the outer steel ring, and transmits them by rolling, so as to reduce the friction in the process of movement and improve the mechanical power. The ball bearing cannot bear too much weight. It is often seen in light industry.

slewing bearing

The design of a ball bearing consists of four basic units:
Ball: The ball is made of high-chromium steel, with certain rolling properties and strength, and the hardness is between 61-65;Inner ring and outer ring: together form the main components of the ball bearing, the inner ring is inside and the outer ring is outside. During the movement, the inner ring and the outer ring form a concentric shaft rolling;
Cage: The cage is to fix the gap between the inner ring and the outer ring of the balls, to ensure that the balls do not contact each other during the rolling process, and to fully exert the sliding of the balls  effect.

Advantages of ball bearings
LDB Ball bearings have significant energy savings, depending on the sophisticated motion characteristics of
the ball bearings. The friction force of the ball bearing is much smaller than that of the sliding bearing, which reduces the consumption of frictional resistance; the size of the ball bearing is standardized, the maintenance is convenient, and the installation and disassembly are convenient; the LDB ball bearing has a compact structure, light weight, and is used for small industrial equipment; the precision of LDB the ball bearing can be Adjusted according to demand, large load, small wear and long
service life.

Cross Roller Bearing Manufacturer

Cross Roller Bearing Manufacturer

Cross roller bearing  is a special type of bearing with inner ring split and outer ring rotating. Because the separated inner or outer ring is fixed together with the cross roller shaft ring to prevent separation from each other after being loaded into the roller and spacer, it is easy to operate when installing the cross roller shaft ring. Because the rollers are cross arranged, only one set of cross roller shaft rings can withstand loads in all directions, and the rigidity is increased by 3 to 4 times compared with traditional models. At the same time, because the inner ring or outer ring of the cross roller bearing is two separate structures, the bearing clearance can be adjusted, even if the preload is applied, it can also obtain high-precision rotating motion.

The rollers of cross roller bearings are arranged at right angles to each other between the inner and outer wheels. They can withstand loads from all directions (such as axial, thrust or momentum loads) at the same time. Because the roller is in linear contact with the track surface, the possibility of bearing elastic deformation under load is very small. This type of bearing is widely used in industrial automatic robots, work machinery and medical facilities, etc., where high rigidity, tight and high speed can still ensure accuracy.

In cross roller bearings, because the cylindrical rollers are arranged vertically to each other through the spacer, a cross roller bearing can withstand radial load, axial load and torque load in all directions. The size of the inside and outside the circle is a minimum of miniaturization, especially extremely thin type is close to the limit of small size, and high rigidity, so the most suitable for industrial robot joint department or rotate department, machining center of rotary worktable, manipulator rotate, precision rotary worktable, medical machine, meter, IC manufacturing devices use.

What is the “cross” of roller bearing

The cross roller bearing is easy to operate when installing the cross roller shaft ring because the inner or outer ring which is divided is fixed together with the cross roller shaft ring to prevent separation from each other after being loaded into the roller and spacer. Because the roller is cross arranged, so only 1 set of cross roller shaft ring can bear the load in all directions, compared with the traditional model, the rigidity is improved 3~4 times. At the same time, because the inner ring or outer ring of the cross roller bearing is two separate structures, the bearing clearance can be adjusted, even if the preload is applied, it can also obtain high-precision rotating motion.

Features and advantages of cross roller bearings:

1, With excellent rotation accuracy

The internal structure of cross roller bearing adopts 90° vertical cross arrangement of rollers.
The rollers are equipped with a spacer or isolation block to prevent the rollers from rubbing each other. In addition, there will be no roller contact phenomenon or lock phenomenon; At the same time, because the inner and outer rings are divided structure, the clearance can be adjusted, even if the preload is applied, also can obtain high precision rotary motion.

2. Simplify operation and installation

The outer or inner ring, which is divided into two parts, is fixed together after the roller and retainer are loaded, so the operation of installation is very simple.

3, Bear large axial and radial load

The rollers are arranged perpendicular to each other by spacer on a 90° V-groove rolling surface.

4, Greatly save installation space

The size of the inner and outer ring of the cross roller bearing is minimized, especially the ultra-thin structure is close to the limit of small size, and has high rigidity. So the most suitable for industrial robot joints or rotating parts, machining center of the rotary table, manipulator rotating part, precision rotary table, medical instruments, measuring instruments, IC manufacturing devices and a wide range of uses.

5. High speed capacity

6. Reduce shaft length and machining cost, thermal expansion leads to limited changes in geometric dimensions

7. Nylon separator, low moment of inertia, low starting torque, easy to control Angle division

8. Optimized preload, large stiffness, high precision of guide roller operation

9. Carburized carbon steel provides excellent impact resistance and surface wear resistance

10. Simple but well lubricated

Features and advantages of cross roller bearing

1. Cross roller shaft has the characteristics of high rigidity, accuracy and easy installation. Mounting holes allow them to be quickly fixed to components. Cylindrical roller of this type .Also equipped with isolation block.

2. Cross roller bearings have strong, non-detachable inner and outer ring structures, which can easily achieve high stiffness and high accuracy without being affected by surrounding structures. Bearing optimum for medium to high speeds, bearings are fitted with isolation blocks between cylindrical rollers to provide smooth rotation.

3. The outer diameter of cross roller bearings is small and the width is narrow. If you need high performance and take up less space, you can also choose to use cross roller bearings.

Because the cross roller bearing is divided into two parts of the outer ring or inner ring, after loading the roller and reholder, is fixed together, so the installation operation is very simple, and the high precision characteristics of the cross roller bearing, the accuracy can reach P4/P2 level, smaller volume, so that the host more space saving.



Slewing Ring Turntable

Generally speaking, slewing ring turntable are large-sized rolling bearings that can withstand axial, radial and moment loads in any direction, alone or in combination. Turntable bearing can perform both slewing (oscillating) motions as well as rotational motions.

Basically, the slewing ring turntable consists of an inner ring, an outer ring and rolling elements (balls or cylindrical rollers), which are separated by polyamide gaskets. One of the bearing rings, which usually contains gears, is provided with holes to accommodate the connecting bolts.

These holes threaded. Typically, only the raceway in the ring is hardened and precision ground. Integral seals made of acrylonitrile butadiene rubber (NBR) retain lubricant inside the bearing and contaminants outside the bearing. The slewing bearings turntable is relubricat by grease fittings to reduce maintenance and operating costs.

Slewing bearing turntable arrangements offer many design and performance advantages over traditional pivot arrangements. We have simplified the compactness and large inner diameter of the relevant parts of the slewing ring, which is more in line with the modern industrial design.

The bearing ring section height of these bearings means that the pinion rod can be kept short. In most cases, only the planes on the relevant parts are required.

Slewing rings turntable were originally designed to be mounted only on horizontal support structures, but can now be used successfully for vertical bearing arrangements.

Slewing bearings excel in a variety of applications, such as:

  • Spider Lift Access Platforms / Rail Access Platforms
  • Bucket Wheel Excavator Bearings
  • Transfer arm bearing
  • Cranes of all types
  • Small excavators, medium excavators and large excavators Slew Bearing
  • Indexing tables
  • Ladle Turrets Slew Bearing
  • Offshore applications
  • Robots Bearing
  • Railway Bogies
  • Rotary Platforms Slewing Bearing Turntable
  • Stackers Slewing Bearing
  • Solar Mirrors Slew Drive
  • Tunnel Boring Machines
  • wind turbines / Pitch bearing

New Wind Turbine Bearings

The operational challenges for wind turbines cannot be overestimated

Increased turbine power and size,extreme weather conditions, heavy loadsn and remote locations are just a few.

LDB has developed an innovative slewing bearing design with enhanced sealing capabilities and redesigned internal geometry to meet these challenges.

The LDB High Endurance Slewing Bearing offers increased resistance to harsh environmental conditions to improve reliability and performance and extend bearing service life.

Design, material and knowledge engineering combine for high endurance New internal bearing geometry in the cage and raceways reduces friction and increases turbine and pitch control performance. Reduced friction contributes to pitch system effectiveness and efficiency to maximize energy production.

A new seal material, manufactured from polyurethane, provides better resistance to ozone, UV and salt water, reducing wear and providing longer service life than traditional nitrile-based sealing solutions.

The seal design is engineered to be less sensitive to ring deformation during operation for improved sealing efficiency,reducing grease leakage and water ingress, which results in improved robustness and lower maintenance costs.

The innovative way the bearing and seal are attached provides simplified installation and replacement, while at the same time the seal efficiency is maintained despite ring deformations under maximum operating loads.


  • Increased turbine reliability even in harsh environments
  • Extended seal and bearing service life
  • Reduced operation and maintenance costs
  • Improved pitch control for increased performance
  • Reduced installation and replacement time


Typical applications

Pitch bearings to optimise the blade position for different wind conditions

Yaw bearings to correctly position the nacelle during operation

LDB offers a complete approach

As the world leader and innovator in bearing technology for more than 100 years, LDB has a unique understanding of rotating equipment and how machine components and industrial processes are interrelated, in every major industry worldwide. This knowledge – coupled with our expertise in sealing solutions,lubrication systems, linear motion,machinery maintenance, mechatronics,and services – enables us to deliver real-world solutions that help maximize mechanical performance over the entire lifecycle of an asset. As a result, LDB is your single source for off-the-shelf and customized technology products,solutions and services.

  • LDB High Endurance Slewing Bearing
    Improved performance and reliability to meet wind industry demands
  • New seal design
    Improved seal function under high loads, reducing lubricant leakage and water Ingress
  • EcoPur seal material
    Increased resistance to wear, UV, ozone and salt water, improving seal reliability and service life even in harsh environments
  • Optimized cage design
    Adjustments to the cage design and a special coating reduce the internal friction of the bearing
  • Optimized raceway design
    Reduced internal friction and increased service life

Wind Turbine Bearings Market | LDB