Investigation of flexible radial ring rolling for production of non-axially symmetric seamless rings on radial axial ring rolling mills

在径向轴向环件轧机上生产非轴对称无缝环的柔性径向环件轧制研究

• 批准号: 454751242
• 负责人: Professor Dr.-Ing. Gerhard Hirt
• 金额: --
• 依托单位: Institut für Bildsame Formgebung (IBF)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2021
• 资助国家: 德国
• 起止时间: 2020-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/454751242?language=en
• 关键词: Investigation; flexible; radial; ring; rolling

The ring rolling process is used to produce seamless rings made of different materials in a wide geometric spectrum. The geometric flexibility is one of the main advantages of this production process. Demand for near net shape geometries to reduce material and post-processing costs led to the development of processes to manufacture rings profiled in radial and axial directions by applying shaped tools. By using innovative tool and process control concepts the producible geometric variety was increased without reducing the process flexibility, as is the case for shaped tools. All of these process variants allow manufacture of profiled rings with constant cross sections around their circumference. There is also demand for seamless rings with non-constant cross sections around the circumference, e.g. for eccentric bearings, but these cannot yet be produced in the ring rolling process.The project described here aims to further develop the ring rolling process in order to enable near net-shape production of such eccentric ring geometries. This can be achieved by performing a targeted closing and opening movement of the mandrel depending on the circumferential motion of the ring in the machine. A necessary mechanism to measure the ring’s rotation was already installed in both guide rolls of the ring rolling machine at the Institute of Metal Forming of the RWTH Aachen University. The provided information will then be transmitted into the machine’s control to allow for real-time control of the tool’s motions based in this information. Additionally, by use of an existing finite element model the producibility of such ring geometries was shown in principle by using the aforementioned process control, which was done in a simplified way using a reference point on the ring to control the mandrel movement. Here it is necessary to implement the method used in the experiments into the simulation to consider potential loss of contact of the guide roll(s) with the ring. In further steps, process influences and boundaries will be investigated by use of the simulation. After successful implementation of the measurement system as well as realisation of the tool motions the numerical results will be verified experimentally by producing two ring geometries with different height-to-wall thickness ratios and potential additional influencing parameters will be identified. The first geometry is expected to be comparatively easy to produce while the second geometry shows more narrow boundaries resulting from a lower ring stiffness. In a second phase the project’s focus will be improvement of the process control, production of rings with several thick sections and the effect of locally different strains on the microstructure of the rings.

环件轧制工艺用于生产由不同材料制成的各种几何形状的无缝环件。几何形状的灵活性是这种生产工艺的主要优点之一。为了降低材料和后处理成本，对近净形几何形状的需求导致了通过应用成形工具来制造在径向和轴向方向上成型的环的工艺的发展。通过使用创新的工具和过程控制概念，可生产的几何形状的多样性增加，而不会降低工艺灵活性，就像成形工具一样。所有这些工艺变型允许制造在其圆周周围具有恒定横截面的异形环。此外，还需要圆周截面不恒定的无缝环件，例如偏心轴承，但这些环件目前还无法在环件轧制工艺中生产。本文所述项目旨在进一步开发环件轧制工艺，以实现此类偏心环件几何形状的近净形生产。这可以通过根据环在机器中的周向运动执行心轴的目标闭合和打开运动来实现。RWTH亚琛大学金属成形研究所的轧环机的两个导辊上已经安装了测量环旋转的必要机构。然后，所提供的信息将被传输到机器的控制中，以允许基于该信息实时控制工具的运动。此外，通过使用现有的有限元模型，原则上通过使用上述过程控制示出了这种环几何形状的生产，该过程控制以简化的方式使用环上的参考点来控制心轴运动。这里，有必要将实验中使用的方法实施到模拟中，以考虑导辊与环的潜在接触损失。在进一步的步骤中，将通过使用模拟来研究过程影响和边界。成功实施后的测量系统以及实现的工具运动的数值结果将通过实验验证，生产两个环的几何形状具有不同的高度，壁厚比和潜在的其他影响参数将被确定。预计第一种几何形状相对容易生产，而第二种几何形状由于环刚度较低而显示出更窄的边界。在第二阶段，该项目的重点将是改进过程控制，生产具有多个厚截面的环，以及局部不同应变对环微观结构的影响。