Maintenance of slewing ring (bering) in high temperature operating environment.
1. Which carriers use slewing rings to operate in high temperature environments
The slewing bearing of the ladle turret has a relatively poor working condition and is subject to high axial load and overturning moment. These loads are transmitted and received by the ring gear, the raceway of the raceway and the gear, so the slewing bearing is on the selected material. It is necessary to consider the tensile strength, compressive strength and fatigue strength of the material to be high and have sufficient toughness and wear resistance. The single-row four-point contact slewing bearing can simultaneously bear radial force, axial force and overturning moment, and is widely used.
In view of the bearing capacity of the slewing bearing in high temperature environment, based on the thermal stress analysis of the slewing bearing, the contact angle, the rolling element radius r, the raceway radius R and the rolling element radius r ratio, the hardened layer depth and Five aspects of the raceway hardness are proposed to improve the bearing capacity of the slewing bearing. Orthogonal test analysis is carried out for these factors, and the optimal combination of parameters is found to reduce the contact stress on the slewing bearing raceway and improve the slewing bearing at high temperature. The bearing capacity provides a theoretical basis for the structural optimization of the high-temperature single-row four-point contact slewing bearing.
2. Precautions for slewing bearing high temperature operation
The slewing bearing is a new type of mechanical parts that has gradually emerged in the world for nearly forty years. The slewing bearing is a mechanical force transmission basic component that needs relative rotation between the two parts and simultaneously receives axial force, radial force and overturning moment. Its basic function is to fix it on the upper and lower supports of the mechanical equipment by bolts. The force transmission and transmission realize the relative rotation between the two parts of the mechanical equipment. The domestic slewing bearing market was originally mainly in the construction machinery industry.
The largest single-row four-point contact ball slewing bearing accounted for more than 95% of the total market share, and the diameter of the raceway was between Φ500 and Φ1500mm. Most of them have a small processing difficulty, a broad market, and low equipment cost. With the continuous development of engineering machinery, wind power industry, heavy-duty vehicles, metallurgical machinery, petroleum industry, military industry, etc., slewing bearings have been more widely used, and are also required to have more and better performance, one of which is the requirement With high temperature resistance, bearing raceways, cages, seals and lubricants can withstand certain high temperatures and maintain their performance.
High temperature slewing bearings for specific applications, in addition to withstand the alternating pressure, also withstand alternating temperature changes, which will produce fatigue, creep and their interaction. In order to ensure the mechanical properties and life of the product, higher requirements are put forward from material selection, machining process, heat treatment process, to corresponding tooling equipment and testing instruments.
3. How to maintain the slewing ring running in high temperature environment
The slewing ring is rolled to the inside with a small amount of grease. The activation allows the user to refill the new grease according to different working conditions.
The slewing bearing raceway should be filled with grease regularly. Generally, the ball support is refueled once every 100 hours of operation, and the roller type support is refueled every 50 hours. The special working environment, such as tropical, humid, dusty, large temperature difference and continuous operation, should shorten the lubrication cycle. New grease must be added before and after the machine has been shut down for a long time. For each lubrication, the raceway must be filled with grease until it seeps out from the seal. When filling grease, slowly turn the slewing ring to make the grease fill evenly.
The tooth surface should always be cleaned of debris and coated with the corresponding grease. There should be a lot of comprehensive work factors, and users can also choose the best grease according to specific requirements.
After the slewing bearing has been running for the first time for 100 hours, the pre-tightening force of the bolts should be checked. After every 500 hours of operation, the pre-tightening force must be maintained. Pay attention to the operation of the slewing bearing during use. If noise, shock and power suddenly increase, stop the machine immediately, check the fault, and dismantle it if necessary.
4. Quality requirements for slewing bearings in high temperature environments (blanks and accessories)
There are many manufacturers of slewing bearings, and the quality and price are also uneven. However, the factors affecting the price are mainly the product quality. The product quality gap is also mainly reflected in the quality of raw materials. The price of raw materials and the price of non-tempered products differs by 1000. Multivariate/ton, because the hardness of the material that is not tempered is only 140-170HB and the hardness of the material after quenching and tempering is 207-262HB, which is the biggest gap.
Secondly, the hardness of the raceway also affects the quality of the product. The hardness of the raceway of the Xuzhou Wanda slewing bearing is ≤3mm, and the depth of the hardened layer of the raceway quenching affects the service life of the product.
Once again, the precision control of each process in product processing, our products in the process of processing more than two other processes to ensure that the product is flexible, does not cause jamming or shaking.
Quality is the foundation of an enterprise’s survival and the soul of its development. Therefore, Luoyang Hengguan slewing bearing will provide you with the most cost-effective products. Quality products will also make us go further and further on the road in this industry. Getting better and better.