In the 20s and 70s, the technology of the upper reducer has been greatly developed, and it is closely integrated with the development of the new technology revolution.The development trend of general reducer is as follows:
①High level and high performance.Cylindrical gears generally adopt carburizing, quenching and tooth grinding, and the carrying capacity is increased by more than 4 times, with small size, light weight, low noise, high efficiency and high reliability.
②Building block type combination design.The basic parameters adopt the priority number, the size specifications are neat, the parts are universal and interchangeable, the series is easy to expand and the pattern is refurbished, which is conducive to the organization of mass production and the reduction of costs.
③Diversified types and many variant designs.Get rid of the traditional single base installation method, add hollow shaft suspension type, floating support base, integrated connection of motor and reducer, multi-directional installation surface and other different types to expand the scope of use.
The main factors that promote the improvement of the reducer level are:
①Theoretical knowledge is getting better and closer to reality (such as gear strength calculation method, modification technology, deformation calculation, optimization design method, smooth transition of tooth root, new structure, etc.).
②Adopt good materials and generally use various high-quality alloy steel forgings, and the quality control level of materials and heat treatment is improved.
③The structure design is more reasonable.
④The machining accuracy is improved to ISO5-6 level.
⑤The bearing quality and life are improved.
⑥The quality of lubricating oil is improved.
Since the 20s, my country has successively formulated the standards of a number of general-purpose reducers such as JB60-1130 "cylindrical gear reducer". In addition to the self-made supporting use of the main engine factory, a number of professional reducer manufacturers have also been formed.At present, there are hundreds of enterprises producing reducers nationwide, with an annual output of about 70 general-purpose reducers, which has contributed to the development of my country's mechanical products.
Most of the reducers in the 20s were manufactured with reference to the technology of the Soviet Union in the 60s and 20s. Although they were developed later, they were limited by the design, craftsmanship and equipment conditions at that time, and their overall level was quite different from the level.
Since the reform and opening up, my country has introduced a number of advanced processing equipment. Through the introduction, digestion and absorption of foreign advanced technology and scientific research, it has gradually mastered the design and manufacture technology of various high-speed and low-speed heavy-duty gear devices.The quality of materials, heat treatment and gear machining accuracy have been greatly improved. The manufacturing accuracy of general cylindrical gears can be increased from 179-60 grades of JB8-9 to 10095 grades of GB88-6, and the manufacturing accuracy of high-speed gears can be stabilized at 4-5 class.After some reducers adopt hard tooth surface, the volume and quality are obviously reduced, and the bearing capacity, service life and transmission efficiency are greatly improved, which plays a great role in saving energy and improving the overall level of the main engine.
The power of the high-speed gear reducer (increase) designed and manufactured by my country has reached 42000kW, and the peripheral speed of the gear has reached more than 150m/s.However, the technical level of most reducers in my country is not high, the old products cannot be replaced immediately, and the transition between new and old products will go through a long period of time.