The plastic gear industry ushered in the first national standard. Recently, the National Standardization Management Committee officially released the national standard for plastic gear accuracy"GB / T38192-2019 Definition and Allowable Values of Deviations on the Identical Tooth Surface and Radial Comprehensive Deviations of Gears on the Same Side of Precision Gears for Injection Molded Plastic Cylindrical Gears". Dr. Shi Zhaoyao, leader of the drafting standard for plastic tooth precision, saidAs assessed by the National Gear Standardization Technical Committee, this standard is blank and has reached the international advanced level.

Establishing standards is a requirement in mature markets

Gear, as a kind of transmission device widely used in mechanical transmission, has a long history of development. Since the successful development of fiber nylon in 1935, the polymer synthetic material industry has developed rapidly. A new type of material has been applied to gears to form plastic gears. Compared with metal gears, plastic gears have the advantages of light weight, low inertia, low noise, and self-lubricating. Its products are processed by mold opening, with high production efficiency and low cost. After decades of development, they have been widely used in various industries such as automotive electronics, instrumentation, service robots, home appliances, office automation, and smart home. Especially in the past two decades, with the successful development and modification of high-strength, high-wear-resistant engineering plastics, plastic gears are developing in the direction of bearing higher loads. There is an application trend of "replacing steel with plastic". It can be said that the rapid development of plastic gears is a worldwide trend in the gear field.

However, since the development and application of plastic gears has been growing, China has no plastic gear standards, especially the lack of basic plastic gear accuracy standards, which seriously restricts the development of China's plastic gear industry. At present, there is still a certain gap between the manufacturing level of plastic gears and developed countries, resulting in a passive situation in which China still needs to import a large number of high-grade plastic gears from abroad. If you want to break through this dilemma, you need to start from various aspects such as gear product design, plastic material research and development, injection mold design and manufacturing, new injection molding equipment and new injection molding process research, gear testing and experiments, and so on. Do not open the establishment of a standardized system. However, due to the large differences between plastic gears and metal gears in terms of design requirements, manufacturing methods, and application sites, the formulation of plastic gears' own accuracy standards has considerable complexity, which has become an urgent problem for the Chinese gear industry.

Promote the overall development of the industry

The precision standard of injection molded plastic gears provides a standard basis for the measurement and grade determination of products, which is conducive to ensuring the quality and reliability of the product, thereby guiding the orderly competition and healthy development of the product, and promoting continuous innovation and technological progress in the industry. It can not only regulate the production behavior of enterprises, establish a healthy market order, promote industrial technological progress, but also broaden the procurement channels for enterprises, reduce external dependence, improve work efficiency, and significantly reduce procurement and maintenance costs.

Industry development and international standards

In the process of standard formulation, the standard setting team led by Shi Zhaoyao not only adopted the latest ISO precision standard system, such as terminology, precision grading concepts and tolerance calculation formulas, but also combined with mature technology and experience in plastic gears in China. Formed a precision calculation, measurement and evaluation system of injection gears with Chinese characteristics.

The injection gear has its special characteristics, such as small modulus, tooth profile formed by the mold at one time, and reinforced structure. Therefore, the accuracy of the injection gear and its measurement method cannot be completely equivalent to the ISO1328 and ISO / TR10064 series standards. Although China's injection gear precision standards are not equivalent to ISO standards, they are consistent with ISO in the macroscopic aspect and are in line with international standards as far as possible. The late expert Ouyang Zhixi, who has made a significant contribution to the development of the standard, once stated that "the first task is to develop a plastic gear standard suitable for China's national conditions, which has both Chinese characteristics and operability."

During the formulation of this standard, the ISO1328 standard and related standards in Japan, the United States, and Germany were thoroughly studied. The domestic industry situation was comprehensively considered, and the content of the standard was determined to ensure the advanced nature of the standard. The Secretary-General of the National Gear Standardization Technical Committee, Wang Zhigang, said that the formulation of the standard is quite difficult. From the project's establishment in 2015 to the completion today, it has gone through bumpy bumps. This is a summary of China's plastic gear industry. He hopes that there will be more innovations in the field of small modulus plastic teeth. Next, he looks forward to making breakthroughs in the standardization of strength and life testing of plastic teeth.

---This article comes from China Chemical Industry News