Bearings play a crucial role in port machinery, and the following is the relevant introduction:

Applications in cranes

Shore container crane (shore bridge): The lifting mechanism is a key part of the shore bridge, and the drum bearings in it bear huge tension and frequent start-stop shocks. For example, large cylindrical roller bearings or tapered roller bearings are used, which have high load-bearing capacity and good impact resistance to ensure the safe and fast lifting and descending of the container. The wheel bearings of the trolley running mechanism need to adapt to high-speed operation and frequent steering, and at the same time bear large lateral forces. Generally, special spherical roller bearings or deep groove ball bearings with sealed structure are used to ensure the smooth operation of the trolley on the track and accurately align the container. The bearings of the pitching mechanism are connected to the girder and the column, and bear huge torque and axial force when the crane performs pitching actions. A combination of large thrust roller bearings and spherical bearings is usually used to meet complex force requirements and large-angle rotation requirements.

Tire-type container gantry crane (field bridge): The wheel hub bearing of the tire walking mechanism is one of the key components, which needs to bear the weight of the whole machine and various bumps and shocks when driving on the port ground. The use of reinforced tapered roller bearings or specially designed engineering-specific bearings has good load-bearing capacity and reliability, ensuring that the field bridge can move flexibly in the yard. The bearings of the lifting mechanism are similar to those of the shore bridge, but due to the working characteristics of the field bridge, it may be necessary to pay more attention to the dust and waterproof performance of the bearings, because the dust and moisture in the yard environment are large. For example, a bearing with a multi-seal structure is used to prevent impurities from entering the interior of the bearing and affecting its performance. The bearings of the spreader slewing mechanism need to ensure that the spreader can rotate quickly and accurately to achieve efficient loading and unloading of containers. Usually high-precision crossed roller bearings or slewing bearings are used, which have less rotational resistance and higher accuracy to meet the needs of frequent rotary operation.

Applications in conveyor systems

Belt conveyor: The bearings that drive the drum and redirecting the drum are one of the core components of the conveyor. These bearings need to maintain stable performance under the condition of long-term continuous operation, and bear the tension of the belt and the weight of the material. For example, high-quality spherical roller bearings or cylindrical roller bearings are used, which have good bearing capacity and low friction coefficient, ensuring smooth rotation of the drum and improving conveying efficiency. Although the roller bearings are small in size, they are numerous in number, and their performance directly affects the running noise and energy consumption of the conveyor. Generally, miniature deep groove ball bearings or special roller bearings with sealed structure are used, which have good sealing and wear resistance, adapt to the harsh environmental conditions of the port, and reduce maintenance costs. The bearings in the tensioning device are used to adjust the tension of the belt, and need to have good adjustment performance and reliability. Usually a bearing housing with a threaded adjustment structure or a specially designed tensioning wheel bearing is used to facilitate the operator to adjust the tension according to different working conditions.

Chain conveyor: The bearings of the chain drive sprocket need to withstand large torque and impact loads, while also ensuring the accurate transmission of the chain. For example, the use of large modulus gearbox special bearings or roller bearings with special toothed fit ensures the good engagement of the sprocket with the chain, improving transmission efficiency and reliability. The roller bearings of the conveying chain are the key components of the chain operation, and need to maintain good performance under heavy loads and high-speed operation. Usually high-strength engineering plastic bearings or metal roller bearings with self-lubricating function are used to reduce the running resistance and wear of the chain and prolong the service life of the chain. The bearings in the track and guide device of the conveyor need to ensure the smooth operation and precise guidance of the conveyor. Linear guide bearings or sliding bearings are generally used, which have good precision and wear resistance and are suitable for the long-distance and large-capacity work requirements of port conveyors.

Applications in loading and unloading equipment

Ship loaders and unloaders: The bearings of the cantilever pitch mechanism of the ship loader and ship unloader need to bear huge cantilever weight and dynamic load during work. For example, the use of large thrust joint bearings or the structure of the combination of hydraulic cylinder and bearing realizes the flexible pitch action of the cantilever to meet different ship types and loading requirements. The bearings of the conveyor system are similar to the aforementioned conveyor, but due to the harsher working environment of the loader, higher protection levels and stronger corrosion resistance may be required. For example, bearings made of stainless steel or bearings with special coatings are used to prevent the erosion of the bearings by seawater, salt spray, etc. The bearings of the grab opening and closing mechanism need to withstand greater impact and friction during frequent opening and closing actions. Usually high-strength roller bearings or specially designed grab bearings are used to ensure reliable operation of the grab and improve loading and unloading efficiency.

Stacker and reclaimer: The bearings of the slewing mechanism of the stacker and reclaimer are the key components to realize the large-angle rotation of the equipment, and need to withstand large overturning moment and axial force. Generally, large-scale turntable bearings or slewing bearing bearings are used, which have high bearing capacity and good accuracy to ensure the stable rotation of the equipment during the stacking and reclaiming process. The bearing requirements of the cantilever pitch mechanism and the conveyor belt drive mechanism are similar to other similar equipment, but special selection and design are required according to the working characteristics of the stacker and reclaimer. For example, the bearings of the cantilever pitch mechanism may need to have a larger range of travel and angle adjustment, and the bearings of the conveyor belt drive mechanism need to adapt to the transportation requirements of different materials. The wheel bearings of the walking mechanism need to bear the weight of the equipment and various resistances when driving on the ground of the yard. The use of heavy-duty wheel-specific bearings or bearings with special sealing and lubrication structures ensures the stable running and accurate positioning of the stacker and reclaimer.

Bearing selection and maintenance points

Selection basis: According to the working load and operating characteristics of the port machinery, choose bearings with suitable load-bearing capacity. For example, for heavy-duty equipment, roller bearings or large rotary bearings should be selected; for high-speed operation, high-precision ball bearings or special high-speed bearings should be selected.Consider the particularity of the port environment, such as moisture, salt spray, dust, etc., and choose bearings with good protective properties. For example, use bearings with a sealed structure to prevent moisture, impurities and corrosive substances from entering the bearing interior; choose corrosion-resistant bearing materials, such as stainless steel or special alloys.Select bearings of the appropriate size and shape according to the installation space and structural requirements of the equipment. For example, for space-constrained parts, compact bearings or specially designed non-standard bearings should be selected; for parts that need to be matched with other components, bearings with suitable fitting tolerances should be selected.

Maintenance measures: Regularly check the running status of bearings, including temperature, noise, vibration, etc. By using professional testing equipment and instruments, find abnormal conditions of bearings in time, such as overheating, abnormal noise or excessive vibration, etc., and take corresponding measures for maintenance or replacement. Keep the bearings clean and lubricated. Regularly clean the bearings, remove dirt and impurities on the surface, and add an appropriate amount of lubricating oil or grease. According to the working environment and frequency of use of port machinery, formulate a reasonable lubrication cycle and lubrication method to ensure that the bearings are always in a good lubrication state. For damaged bearings, they should be replaced in time. When replacing bearings, they should be carried out in strict accordance with the operating procedures to ensure the installation quality and accuracy. At the same time, the relevant parts should be inspected and maintained to ensure the normal operation of the entire equipment. Strengthen the training of port machinery operators to improve their awareness and skills in bearing maintenance. Operators should understand the basic working principle and maintenance points of bearings, be able to operate equipment correctly, and avoid damage to bearings due to improper operation.