Sydor Maciej, Waszkiewicz Krystian, Potok Zbigniew
Department of Woodworking and Fundamentals of Machine Design, Faculty of Forestry and Wood Technology, Poznań University of Life Sciences, 60-637 Poznań, Poland.
Department of Furniture Design, Faculty of Forestry and Wood Technology, Poznań University of Life Sciences, 60-637 Poznań, Poland.
Materials (Basel). 2024 Nov 23;17(23):5729. doi: 10.3390/ma17235729.
Many factors affect screw withdrawal resistance (SWR), including screw size, embedment depth, the pre-drilled hole's diameter, dimensional accuracy, and the furniture pieces' material properties being joined. While prior research has extensively examined the influence of these factors, this study aimed to explore a neglected factor: how drill bit wear impacts pilot hole quality and subsequent SWR. The experimental setup included pinewood samples with pre-drilled 5 mm diameter blind pilot holes with a depth of 45 mm. The holes were equally divided into two groups: one drilled with a sharp bit, the other with a blunt bit. Euro-type coarse furniture screws (7 mm major diameter, 4 mm minor diameter, 3 mm pitch) were screwed into all holes. Subsequently, SWR was measured using a universal testing machine. Results show a statistically significant decrease in SWR when using the blunt drill bit. This phenomenon can be explained by excessive local material degradation, increased surface roughness, and disrupted hole dimensional accuracy, collectively hindering SWR. The study's findings offer insights into how excessive drill bit wear impacts the screw withdrawal capacity of pinewood, informing best practices in furniture and construction.
许多因素会影响螺丝抗拔力（SWR），包括螺丝尺寸、埋入深度、预钻孔直径、尺寸精度以及所连接家具部件的材料特性。虽然先前的研究已经广泛探讨了这些因素的影响，但本研究旨在探索一个被忽视的因素：钻头磨损如何影响导向孔质量及后续的螺丝抗拔力。实验装置包括带有直径5毫米、深度45毫米的预钻盲导向孔的松木样本。这些孔被平均分为两组：一组用尖锐钻头钻孔，另一组用钝钻头钻孔。将欧式粗牙家具螺丝（大径7毫米、小径4毫米、螺距3毫米）拧入所有孔中。随后，使用万能试验机测量螺丝抗拔力。结果表明，使用钝钻头时螺丝抗拔力在统计学上显著降低。这种现象可以通过局部材料过度降解、表面粗糙度增加以及孔尺寸精度受到破坏来解释，这些因素共同阻碍了螺丝抗拔力。该研究结果为过度的钻头磨损如何影响松木的螺丝拔出能力提供了见解，为家具和建筑领域的最佳实践提供了参考。
