FSReman - Functional modeling of bolted joints under uncertain product conditions for remanufacturing

再制造是循环经济道路上最重要的环节，涉及废旧产品和产品部件的再加工。由于其可拆卸性，螺栓连接是再制造领域连接的核心要素。螺栓连接的状况决定了重组产品的功能。一方面，腐蚀甚至损坏的螺栓连接会使旋紧过程更加困难，另一方面，由于工艺参数的不利选择，存在对内螺纹永久损坏的风险。如果可能的话，钻出和插入新的螺纹既昂贵又耗时。因此，在使用新螺栓重新紧固时，有必要对剩余的承载能力进行功能导向的陈述。然而，根据目前的研究状况，这是不可能的。本项目的目的是在不确定的产品条件下对螺栓连接进行数据驱动的功能建模。为此，本项目将对螺栓连接进行功能建模。再制造包括将锈蚀螺栓从锈蚀螺纹中拆卸的过程以及将新螺栓插入到再制造的旧部件的螺纹中的下游旋入过程。记录工艺和产品数据，并导出用于重组的螺栓连接的功能模型。通过本项目的研究，验证了预测再制造螺栓连接的承载能力和拧紧过程中螺纹摩擦系数等功能相关变量的功能模型，以及模型开发方法。生成的功能模型基于现有的过程知识和已知模型。随后，将使用本项目收集的由过程和产品数据组成的经验数据库进一步开发功能模型。

Remanufacturing, the most important procedure on the way to the circular economy, deals with the reprocessing of used products and product parts. Due to their detachability, bolt connections represent a central element for connections in the field of remanufacturing. The condition of the bolt connection determines the functionality of the reassembled product. Corroded or even damaged bolt connections can, on the one hand, make the unscrewing process more difficult, and, on the other hand, there is a risk of permanent damage to the internal threads due to an unfavorable choice of process parameters. Drilling out and inserting new threads is - if at all possible - expensive and time-consuming. Therefore, a function-oriented statement regarding the remaining load-bearing capacity when retightening using a new bolt is necessary. However, this is not possible according to the current state of research. The aim of this project is the data-driven functional modeling of bolted joints under uncertain product conditions. For this purpose, a functional modeling of bolted joints is to be carried out in this project. Remanufacturing comprises the disassembly process of a corroded bolt from a corroded thread and a downstream screw-in process of a new bolt into the thread of the remanufactured used part. Process and product data are recorded and a functional model of the bolt connection is derived for reassembly. The result of this project is a validated functional model for predicting functionally relevant variables, namely the load-bearing capacity of the remanufactured bolted joint and the thread friction coefficient during tightening, as well as the method for model development. The resulting functional model is based on existing process knowledge and known models. Subsequently, the functional model will be further developed using the empirical database collected in this project, consisting of process and product data.