In the process of mechanical manufacturing, burrs have become a thorny problem. These seemingly inconspicuous tiny protrusions actually pose a threat to the appearance quality of the workpiece, making its surface rough and uneven. What's more serious is that in the subsequent assembly stage, these burrs will interfere with the precise fit of parts, which will have an adverse effect on the performance and stability of the entire product. In the long run, burrs may also cause wear of parts and even cause serious consequences such as part breakage. Therefore, it is extremely important to deeply explore the root causes of burrs and master a set of effective coping strategies to improve the quality and efficiency of mechanical manufacturing and ensure the reliability of product performance.
1. What are burrs?
Burrs are common on the surface of workpieces, especially in the edge area, in the form of tiny hooks. In the field of high-precision machining, even insignificant burrs may be enough to cause fit errors between parts, thereby affecting the operating accuracy of mechanical equipment. For example, in the manufacturing process of aerospace parts, a tiny burr is enough to hinder the smooth assembly of parts, and in severe cases may even lead to major safety accidents.
2. Causes of burrs
Some inherent properties of metals, such as ductility, toughness and plasticity, although they bring excellent processing adaptability to metals, also bury hidden dangers for the generation of burrs. During cutting operations, the ductility of metals often leads to increased cutting resistance, making it impossible for the material to be cut cleanly, and some of the materials that are not completely removed will remain on the surface of the workpiece, forming burrs. Taking aluminum alloy as an example, due to its excellent ductility, small burrs often form on the edge of the workpiece during milling.
3. Solutions to the burr problem
Tool review and optimization: The condition of the tool has a significant impact on the formation of burrs. Before starting processing, the operator must strictly check the sharpness and hardness of the tool. A sharp tool can cut into the material more smoothly, thereby reducing the deformation and tearing of the material, thereby reducing the probability of burrs; while a tool with insufficient hardness is prone to wear, which will weaken the cutting effect and increase the risk of burr generation. During the processing process, according to the different materials and specific processes used, the contact angle of the tool can be reasonably adjusted to make the cutting process smoother and more efficient, and further reduce the generation of burrs.
Reasonable use of cutting oil: When the tool is cutting, a lot of heat will be generated due to friction. If this heat cannot be dissipated in time, the local temperature of the material will rise sharply, causing the material to deform, affecting the smoothness of cutting, and increasing the possibility of burrs. At present, the method of spraying cutting oil is widely used in mechanical processing to deal with this problem. The main function of cutting oil is cooling and lubrication. It can effectively reduce the temperature of the tool and material, reduce friction resistance, and make the cutting process smoother. Compared with dry processing, wet processing is less likely to produce burrs due to the use of cutting oil. However, different materials and processes have different requirements for cutting oil, so it is necessary to reasonably select the type of cutting oil and control its dosage. If the dosage is too small, the expected cooling and lubrication effect cannot be achieved; if the dosage is too large, it will cause a waste of resources and bring inconvenience to subsequent cleaning work.
Load adjustment: The load that the tool bears during the cutting process is affected by multiple factors such as material deformation, tool rotation speed, feed speed, and cutting depth. These factors are intertwined during the processing process, resulting in constant changes in the tool load. When the load setting is unreasonable, the cutting process will become unstable, which increases the risk of burrs. Therefore, the operator needs to pay attention to the load condition at all times and flexibly adjust the key parameters of the tool such as the rotation speed, feed speed and cutting depth according to the actual situation. For example, when processing materials with higher hardness, the rotation speed and feed speed of the tool should be appropriately reduced, while the cutting depth should be increased; on the contrary, when processing materials with lower hardness, the rotation speed and feed speed can be appropriately increased, while the cutting depth can be reduced.
Optimized design: In the early stage of product design, reasonable design can effectively reduce the generation of burrs. Compared with right-angle design, rounded corner design is less likely to cause burr problems during processing. The reason is that when cutting right angles, the tool needs to change direction sharply at the corner, which will cause a sudden change in cutting force, thereby increasing the possibility of burrs. The rounded corner design enables the tool to achieve a smooth transition during the processing process, reduces the sudden change in cutting force, and thus reduces the probability of burrs. Therefore, in product design, rounded corner design should be used as much as possible, and the use of right angles should be reduced to achieve the purpose of reducing burrs.
Deburring: Due to the characteristics of the material itself or the limitations of the processing technology, it is sometimes impossible to completely eliminate the generation of burrs. In this case, it is necessary to deburr the workpiece after the processing process is completed. Common deburring methods include grinding, polishing and sandblasting. Grinding mainly uses tools such as sandpaper and grinding wheels to manually remove burrs; polishing can further improve the smoothness of the workpiece surface. It can not only effectively remove burrs, but also significantly improve the surface finish; while sandblasting uses high-speed spraying of sand particles to impact and remove burrs, while improving the overall quality of the workpiece surface. For situations with high-precision processing requirements, deburring processing procedures can also be added to CNC machine tools and multi-task machine tools to achieve automation of deburring, thereby improving processing efficiency and quality.
Therefore, in order to effectively reduce the generation of burrs, the key is to deeply explore the root causes of their generation and comprehensively optimize various links such as tool selection, cutting oil application, load management, product design and deburring. Through these comprehensive measures, the probability of burrs can be reduced, the overall quality and performance of workpieces can be improved, and the continuous progress and development of the machinery manufacturing industry can be promoted.(文章来源：UG学习堂小胥收徒)
