Stainless Steel Bearing With The House

As the food industry continually develops toward lightweight,multi-functional and green environmental protection and high reliability,higher performance are required for the structure,performance,and reliability of its bearings.Since the stainless steel mounted bearing has the characteristics of corrosion resistance,rust resistance,strong sealing and maintenance-free,it can be successfully applied in food machines.However,there are no domestic made bearings that are qualified,due to the technical difficulties in the sealing and manufacturing of such bearings,and the supply of such bearings generally relies on NTN and NSK of Japan,SKF of Switzerland,Schaeffler of Germany,TIMKEN of USA and other world-renowned bearing companies.For this purpose,this thesis takes precision stainless steel mounted bearing as the research topic to meet the actual demands of enterprises,and studies on its structural design and optimization,process analysis and improvement,and testing to provide technical support in realizing its domestic production and improvement of the international competitiveness of our company.1.First of all,the main contents of the current research and its background are introduced.Although the mounted bearing develops quickly,the overall process and application cases are still relatively low,and there is still much space for improving its design technique,processing,sealing structure,lubricating performance,special detection technique and experimental technique,especially in some food industries,because their specific working environment,the requirements of corrosion resistance,rust resistance,strong sealing,and maintenance-free for such bearings are severe.With the development of modernization of food machinery and public increased attention to food safety,the requirements for such bearings become higher and higher.2.Through the analysis of the internal structure and performance characteristics of special bearings for food machinery,the general steps of the optimal design of the bearing are explained,and the material selection of the components of the bearing and the influences on the performance of the bearing are analyzed.And based on the available bearing design,the optimal design of the bearing structure is used to further improve the sealing performance of the bearings to meet customer demands.The product structure is special,a dust cover is installed on the housing.an O-ring is installed between the dust cover and the housing,and a dust cover is installed behind the housing.The design with multiple protections makes the bearing in a relatively closed environment,and can greatly and effectively prevent air,dust,or liquid,any impurity,which impair the operation of the bearing,from entering the bearing working environment,and ensure the durablity and well operation of bearings and effectively improve the service life of the bearings.Moreover,the dust cover is yellow color,which also serves as a safety warning.3.In terms of sealing,the overall structure of the bearing is optimized based on original bearing design.A sealing type combing double-lip dust cover with double-lip-retaining ring is developed.Compared with the previous types of sealing,the new type of sealing improves the sealing loops and the effective contact area of sealing lip and rings.Furthermore,the grease filled between the dust cover and the retaining ring ensures the sealing performance and also greatly increases the service life of the bearing.Thus,the product has significant advantages over previous bearings under wet and corrosive working conditions in the food industry.4.The manufacturing process of precise stainless steel spherical bearing is developed.Precision stainless steel spherical bearing not only requires good design method,good design concept,but also the practicability and the processing efficiency should be considered.The batch production has been achieved to reduce the manufacturing cost of the bearing and improved the competitiveness of the product in the market.Therefore,the bottleneck processes,such as external groove grinding,internal grinding,and spherical grinding process,have been analyzed.Furthermore,process improvements and process parameters optimization are carried out to meet the quality requirement of the product.Firstly,hard turning process is applied prior to groove and internal grinding process to reduce the grinding allowance.Secondly,the single crystal grinding wheel and CBN grinding wheel are used for experiments,and set different process parameters.The way of wheel dressing methods is changed from single point dressing to roller dressing to determine the best process parameters,and improve the machining efficiency.Last,the passivation is applied to all surfaces of the bearing,which significantly improves the performance of corrosion resistance and rust resistance,and also prolongs the service life of the bearing.5.Performance test is conducted on stainless steel spherical bearing to verify that the designed and manufactured bearings meet the customer's needs or not,and to provide data for further optimization to achieve continuous improvement.Through a series of experimental processes,such as leaking grease test,salt spray test,and water spray test,on the eight groups of samples,it is concluded that the intended purposes are realized,the service life of a bearing can reach 11,700 hours and the 2 years of maintenance-free can be achieved.This product is a success with fairly advanced structural improvement,manufacturing and processing technology.For the design of precise stainless steel spherical bearing,The design with the use of dust caps,dust,retaining rings,dust covers,O-rings and other components and grease that meet the FDA and NSF certifications of the food industry,makes the bearing is safer and worry-free in use.Emphasis is placed on the design improvement of the bearing seal structure.At the same time,a complete set of processing technology is also developed through experiments and trial production.It is possible to improve the machining efficiency and reduce production cost with current process equipment by improving the abrasives,process parameters,and dressing methods.Tests show that the main performance indicators of the developed SS-UCF208 bearings have reached or even exceeded the advanced level of similar products of internationally renowned bearing companies,thus the advanced nature and practicality of design optimization methods and process methods are verified.The high-speed stainless steel mounted bearing developed by this thesis has been recognized by the Danaher Company and end-customer Coca-Cola Company,and batch orders are obtained and open up the market for the US food industry.The technical results achieved in this thesis have great significance in improving China's bearing design and manufacturing level.