Technology Researching On Box Parts Of Heavy-duty Vehicle Transmissions And Fiexible Manufacturing Line Programming

With the fast development of national highway,the demand is growing stronger on multi-speed transmissions in Heavy-duty vehicle market. In 2002 the company introduced a multi-speed transmission MPT21B design and manufacturing technology, established a multi-speed gear box design platform. In order to meet the market for multi-file demand for high torque gearbox, we designed the DC9J150T, DC12J150T gearbox .In the design of the new products, we used more new technologies on forced lubrication, oil cooling. In order to improve the productive capacity, the company investmented and built a production base forming an annual output capacity of 3 million units transmission. The manufacturing lines are Composed by Japan Makino (MAKINO) machining centers wih using of motorized roller on transmission, producting, leak testing, on-site SPC inspection, and cleaning .The main contents of the dissertation are about of the process methods of the box parts and planning of the flexible manufacturing line.Box parts have the specialities which are complex, of relatively large size, of heavy weight, and more difficult in processing. Firstly, I make scientific researches on the structure, processing techniques, processing equipment, cutting tools and other aspects of the box parts. Then ,I focused on the processing techniques of the box parts of the heavy-duty truck transmission (the company's products). Through processing the sample production , I identified the current shortcomings in processing methods. Then,I made a planning in order to ameliorate the machining processes,the cutting tools,the tooling,and so on .With the increasing diversification of product demand, product upgrading, shorter the life cycle, Volume varieties (especially small and medium-volume) production is the main form of machinery manufacturing. In order to improve market share, the company continue to introduce new productions.Since becaming a number of China Heavy Duty Truck, the main products of the company are replaced by HW series transmissions, the old production lines have been unable to meet the requirements of mass production of many varietly.The main produces of the company are two series of heavy-duty truck box parts, one for DC12J150T series transmissions, the other for HW series transmissions. Two series of heavy-duty box part are not the same from the structure, size, weight ,and the tooling, cutting tools are not the same. The current production line is for the DC12J150T transmission projects ,the annual output of 3 million units in 2002.And the cutting tools, tooling, testing and logistics are only for this one. It is very suitable for flexible manufacturing line (FML) to improving Production capacity.Firstly, according to the production of the company, I made the process course. Some of the box parts were relegated to the other manufacturers. At the same time inorder to exert the Makino horizontal machining center on production efficiency, the HW series gearbox parts roughing were relegate to copartners.Considering various factors, the best way is to transform the current production line in order to product the HW series gearbox and the DC9J150T, DC12J150T series gearbox. I studied the flexible manufacturing system because of the automatic processing systems,the logistics systems,the information systems, and the software systems. According to the characteristics of the productions, I selected an existing Makino machining center as the main equipment, designing of the interchangeable tooling,and used much the common tool, logistics with the automatic car and the world's leading information systems and software systems. I used the MMC (Makino flexible transformation of the system) software for the analysis of production capacity to meet the premise of a clear demand for the number of all kinds of tooling. And I researched the tightness testing equipment, used the existing parts of the auxiliary equipment to avoid repetitive investment. Based on the results, I made the flexible line plan.After the company into The China Heavy Duty Truck Group,it become more importantly for product updates. The researching is of important significance. After much deliberation, the Expert Group decided to adopt the flexible line plan.