Tube Bending Experiment Dataset

In order to obtain the data required for training and testing ML algorithms, a total of 150 tube bending experiments were performed. All the tubes were made of AISI 316 austenitic stainless steel material and the bending radius was determined as 72.9 mm. Bending parameters were selected as (1) tube outer diameter, (2) tube wall thickness, (3) bending angle, (4) the distance of the mandrel to be used to the bending axis, and (5) mandrel type. The parameter values selected for the experimental test study are given dataset. The test results were either ACCEPT (1) or REJECT (0).
Before beginning the tests, in order to avoid any confusion during and after the study, the parameter values were coded on the samples.
In order to carry out the experimental tests in the data list, die sets (bending die, pressure die, clamping die and suitable mandrel type) appropriate for the determined tube types were connected to the CNC machine, respectively; then the final adjustments were made before the bending process. A great attention was paid to adjust the distance of the mandrel to the bending axis.
For each test to be performed, 3D model of each tube to be bent was designed using Siemens NX drawing software in accordance with the specifications determined in the experiment list. The assembly drawings were created and the intersection coordinates of the principal axes of the designed tubes were listed. Then the codes were written to perform the bending operations on the CNC bending machine and manually entered in the control unit of the CNC machine; in addition, simulations were performed to check the risk of the workpiece hitting the workbench.
After gaining the confidence of a safe bending, the workbench was made ready for the process. The tubes were cut on the band saw according to the layout sizes in the technical drawings. Machining burrs formed on the cutting surfaces of the cut tubes were removed by using appropriate sandpaper in the deburring machine. Before starting the bending process, hydraulic oil was applied to the mouth of the pipe and the arbor of the CNC to provide lubrication. Then, the tube was passed through the mandrel connected to the CNC machine and given the start, the bending process started. The experimental study was carried out on an Italian Macri 6-axis CNC tube bending machine (Ø18mm to Ø60mm diameter bending capacity).
Upon the completion of the process, the bench was brought to the safe position and the bent tube was taken out of the bench. The conformity of the bent tube to the manufacturing technical drawing was checked.
According to the quality control, the bending process was considered either successful for the samples free from measurement errors and visual defects (ACCEPT), or unsuccessful for the samples having measurement errors and/or visual defects (REJECT). The number “1” was written on the accepted test samples and “0” on the rejected test samples, and the results were also recorded in the experimental data list.

为获取训练和测试机器学习算法所需的数据，共进行了150次管材弯曲实验。所有管材均由美国钢铁学会316型奥氏体不锈钢制成，弯曲半径设定为72.9毫米。实验中选定的弯曲参数包括：（1）管材外径，（2）管材壁厚，（3）弯曲角度，（4）芯轴至弯曲轴的距离，以及（5）芯轴类型。实验测试研究中选定的参数值包含在本数据集中。测试结果为接受（1）或拒绝（0）。在测试开始前，为了防止研究过程中及之后出现任何混淆，参数值已在样品上进行了编码。为了在数据列表中实施实验测试，针对确定的管材类型，分别连接了合适的模具组（弯曲模具、压力模具、夹紧模具及相应的芯轴类型）至数控机床；随后在弯曲工艺前进行了最终调整。特别关注了调整芯轴至弯曲轴的距离。对于每个将要进行的测试，使用西门子NX绘图软件根据实验列表中确定的规格设计了每个待弯曲管材的3D模型。创建了装配图，并列出了设计管材主轴的交点坐标。然后编写了代码以在数控弯曲机上进行弯曲操作，并手动输入数控机床的控制单元；此外，还进行了模拟以检查工件碰撞工作台的风险。在确保了安全的弯曲之后，工作台被准备好以进行工艺流程。根据技术图纸上的布局尺寸，使用带锯将管材切割。通过使用适当的砂纸在除毛刺机中移除了切割表面形成的加工毛刺。在开始弯曲工艺之前，向管材的末端和工作台的轴颈施加了液压油以提供润滑。然后，将管材通过连接到数控机床的芯轴进行传递，并启动了弯曲过程。实验研究是在意大利Macri 6轴数控管材弯曲机（直径范围从Ø18mm至Ø60mm）上进行的。工艺完成后，将机床移至安全位置，并将弯曲的管材从机床中取出。检查弯曲管材是否符合制造技术图纸的要求。根据质量控制，弯曲工艺对于无测量误差和可视缺陷的样品被认为成功（接受），而对于存在测量误差和/或可视缺陷的样品被认为不成功（拒绝）。在接受的测试样品上写上数字“1”，在拒绝的测试样品上写上“0”，并将结果也记录在实验数据列表中。