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.

环轧工艺用于生产由不同材料制成的各种几何形状的无缝环，几何形状的灵活性是该生产工艺的主要优点之一，从而满足了对近净形状几何形状的需求，以减少材料和后加工成本。通过应用异形刀具来制造径向和轴向异形环的工艺的开发通过使用创新的刀具和工艺控制概念，在不降低工艺灵活性的情况下增加了可生产的几何形状，就像所有这些工艺一样。允许异形环的变型制造圆周上具有恒定横截面的无缝环也有需求，例如偏心轴承，但这些还无法在环轧工艺中生产。这里描述的项目旨在进一步开发无缝环。环轧制工艺，以实现这种偏心环几何形状的近净形生产。这可以通过根据环在机器中的圆周运动进行有针对性的闭合和打开运动来实现。戒指的亚琛工业大学金属成型研究所的环轧机的两个导辊中已经安装了旋转系统，所提供的信息将被传输到机器的控制系统中，以便实时控制工具的运动。此外，通过使用现有的有限元模型，原则上通过使用提到的过程控制来显示这种环几何形状的可生产性，这是使用环上的参考点来控制心轴运动以简化的方式完成的。有必要将实验中使用的方法应用到模拟中，以考虑导辊与环的潜在接触损失。在成功后，将通过使用模拟来研究过程影响和边界。测量系统的实施以及工具运动的实现，将通过产生具有不同高度与壁厚比的两个环几何形状来对数值结果进行实验验证，并且将确定第一个几何形状。相对容易生产，而第二个几何形状显示更窄在第二阶段，该项目的重点将是改进工艺控制、具有多个厚截面的环的生产以及局部不同应变对环的微观结构的影响。