| Remanufacturing is the ultimate form of automotive products recycling, which can recapture most value added in the components, and it will be one of the most important technological methods for the sustainable development of automotive industry circular economy, and will be the necessary choice in order to establish the resources-conservation and environment-friendly harmonious society.Remanufacturing belongs to the manufacturing category, but is not equal to manufacturing process. The difference is that the original condition of rough components in manufacturing is pure, the quality, reliability and products consistency could be easily controlled. While the rough components in remanufacturing come from end-of-life automotive products, most components have failed with a variety of unknown age distribution. Each component of the remanufactured system may have come from different failed products, experienced different remanufacturing techniques and may be a new component of the same type as the original one or different. The condition of cores, failure modes and remanufacturing methods of raw materials are random and uncertain. So the quality control method will be more complex than that of manufacturing. Remanufacturing is also different from repairing process. Repairing is stochastic and single process aiming to recover the products function, while remanufacturing is a volume-wasting and renewing process, which involves the production-batch disassembly, cleaning, replacement or refurbishment of worn components and reassembly process. The system reliability is required to not be lower than the original system reliability. So the reliability modeling and analysis methods will be different from that of manufacturing and repairing process.Automotive components remanufacturing industry has a history of more than 50 years in some developed countries, a complete remanufacturing system formed from technical standards, processing techniques, fabricating machinery to reverse logistics and delivery, etc. While automotive components remanufacturing industry in China is just at the preliminary stage. With the consideration of transportation safety and environment protection, the Chinese government has been prohibiting the reuse and remanufacturing of important ELVs components, such as the engine, transmission, steering gear, front/rear axles and the vehicle frame, etc. These components have high value-added, but all of the five assemblies must be broken down and resmelted. This has caused a lot of resources waste and secondary pollution. In order to develop the circular economy of automotive industry, the Chinese government begins to promote the development of automotive components remanufacturing industry, and express high requirements on remanufactured automotive products so as to ensure the technical function, system reliability and products lifetime can be not lower than or reach the original products requirement.Remanufacturing has an uncertain characteristic on coming time, technical condition and repairing method of cores, and the remanufactured system is different from that of original one. So how to assess and improve the system reliability of the remanufactured products is the key question to develop the automotive components remanufacturing.In this paper, it focuses on the basic theory of product reliability, automotive remanufacturing modes, reliability modeling method of remanufactured automotive products and the reliability prediction, allocation and reliability experiment are also discussed in detail. It also points out two aspects that affect the system reliability of remanufactured automotive products, such as the change of system construction and reliability of components in the remanufactured system. According to the variation of automotive products technical level in remanufacturing, it puts forward four kinds of remanufacturing style, such as evolutional style, stagnant style, and degenerate style, transformational style, etc. According to the different construction of remanufactured products from the original ones, it puts out four kinds of remanufacturing modes, and they are reuse mode, updating mode, and amelioration mode, reset mode, etc.Reliability models are established on the base of these four different remanufacturing modes, and the reliability prediction and allocation methods are discussed deeply based on the series system and exponential distribution. In the end, the demonstration reliability experiment of remanufactured automotive products and the FMEA of remanufacturing are also analyzed. Take the remanufactured diesel engine as example, the engine was remanufactured with the reuse mode, some key components were remanufactured by high surface technologies. Assess these key components and system reliability by 1000h reliability experiment, the final results show that key components and system reliability are not lower than that of original requirements.The preliminary main research builds a relatively complete theory on automotive components remanufacturing modes, reliability prediction and allocation method. It can be used as a guide for the classification principle of reuse components, remanufacturable components and abandoned components in remanufacturing, and it gives a theory support on the selection of these three types of components and help the remanufacturers to better the system reliability of remanufactured automotive products. While the automotive components remanufacturing industry in Chinese is just at the preliminary stage, there are few remanufacturers, remanufactured products and technics, so it is hard to get more remanufacturing modes and reliability data to support this paper, and it needs a further consideration in the future.
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