During the last decade a special drilling method called orbital drilling (OD) was investigated in many directions. The process is described by a complex geometric machining setting due to the three dimensional tool path and the superimposed rotary cutting motion. Comparing to standard mill or drill operations this motion causes highly changing conditions regarding the chip formation for each cutting edge of the tool and forms a complex shape of the bore bottom. For primitive tool geometries and certain process specifications, several analytical approaches to calculate the geometrical cutting conditions were published. However, it is still difficult to calculate or visualize the cutting conditions for each cutting edge in an arbitrary OD-operation and especially for free formed tool geometries. As a matter of fact the understanding of the details of OD is still limited. The objective of this study is to derive a more universal approach for the geometrical description of the uncut chip thickness in OD-processes. The approach is realised in a prototype of a simulation software (SSW) that calculates a virtual material removal by a numerical algorithm based on a workpiece representation consisting of so called Dexel elements combined with a residuum strategy. In contrast to many common tool engagement simulations, this paper presents a method that is focussed on a calculation of the engagement condition for each cutting edge of the tool. By means of this method it is possible to simulate and visualize a virtually arbitrary OD-process. To proof the accuracy of the simulation a comparison to an analytical model for a standard tool type was carried out. Furthermore the SSW was applied for an analysis of a concave front cutting profile of an OD-tool. Due to this application a mathematical description for a full front cut could be derived.

在过去的十年中，在许多方向上研究了一种称为轨道钻探（OD）的特殊钻探方法。由于三维刀具路径和叠加的旋转切削运动，通过复杂的几何加工设置来描述该过程。与标准铣削或钻孔操作相比，该运动导致有关刀具每个切削刃切屑形成的条件发生了很大变化，并形成了复杂的孔底形状。对于原始的刀具几何形状和某些工艺规范，已发布了几种计算几何切削条件的分析方法。然而，仍然难以以任意的OD操作来计算或可视化每个切削刃的切削条件，尤其是对于自由成形的刀具几何形状。实际上，对OD细节的理解仍然有限。这项研究的目的是为OD工艺中未切屑厚度的几何描述提供一种更通用的方法。该方法是在模拟软件（SSW）的原型中实现的，该软件可通过数值算法基于工件表示（包括所谓的Dexel元素和残差策略）来计算虚拟材料的去除量。与许多常见的刀具啮合模拟相反，本文提出了一种方法，该方法侧重于工具每个切削刃的啮合条件的计算。通过这种方法，可以模拟和可视化几乎任意的OD过程。为了证明模拟的准确性，与标准工具类型的分析模型进行了比较。此外，SSW还用于分析OD工具的凹形前切削轮廓。由于该应用，可以得出全切边的数学描述。