Dalian Fuhong Machinery Co., Ltd

Tag: Cutting technology

  • What Is The Small Round Hole On The Knife For?

    What Is The Small Round Hole On The Knife For?

    What is the small round hole on the knife for?

    There are many factories, and when pursuing holes that require high-precision machining , the rationality of process selection is often ignored. Drilling and reaming only belong to the category of rough machining, and this kind of rough machining cannot meet high requirements higher than IT6 level accuracy. Under such circumstances, reaming has become a key link. It can significantly improve the quality of the hole with the help of micro-cutting and extrusion polishing.

    Reaming is not just about making the hole larger. It is a composite process that combines the three actions of cutting, extrusion and correction. It can stably achieve extremely high dimensional accuracy. For precision parts, this stability is very critical, especially for those connection parts where there are strict requirements for fit clearance.

    Core principles revealed

    镗削加工质量控制要点_精密小孔铰削加工_IT6级铰削工艺

    The reason why reaming is so precise is that it removes an extremely thin layer of metal, usually only in the range of 0.01 to 0.05 millimeters. This minimally invasive processing method generates extremely little cutting force and heat! Not only will the workpiece not be deformed due to overheating, the tool will not be deformed due to excessive force, thus ensuring the final geometric accuracy.

    It is said that the design of this reamer is very particular. It has a relatively large number of teeth and also has a wiper blade. This not only allows the hole diameter to be calibrated, but also flattens the previously made knife marks to prevent the hole wall from showing ripples, even when processing micro holes with a diameter of less than 1 mm. For this, the tolerance can be extremely strictly controlled within 0.005 mm, and the effect is really amazing.

    Material matching skills

    精密小孔铰削加工_镗削加工质量控制要点_IT6级铰削工艺

    The reaming parameters applicable to workpieces made of different materials will be different. For soft materials such as aluminum alloy and copper, it is recommended to use high-speed steel reamers. The cutting speed can be maintained at 20 to 40 meters per minute. This parameter setting can make the cutting process smoother, prevent tool sticking, and thus improve the surface finish.

    If the material is carbon steel or cast iron, cooling lubricant must be added to assist processing. Although the rotation speed can be appropriately reduced, the feed speed must remain uniform and stable. For plastic parts, it is recommended to use a reamer with a floating guide bush, which can effectively prevent edge cracking, ensure the integrity of the hole, and reduce the workload of subsequent trimming.

    Key operating points

    All experienced mechanics know that the reserve amount of the bottom hole directly determines the success or failure of reaming. If the allowance is too small, the reamer will not be able to perform effective cutting; if the allowance is too much, the cutting force will be too large, which may easily cause the tool to break. And generally speaking, it is necessary to accurately calculate and reserve an appropriate margin based on the hole diameter and material conditions. This is the first step to ensure processing quality.

    The details of the operation when entering the tool cannot be ignored, nor can the details of the operation when retracting the tool be ignored. Reverse rotation is strictly prohibited during reaming, otherwise the reamer tooth edge will be easily damaged. In addition, the ratio of coolant is also very critical. It is recommended to use water-soluble oil diluted at 40:1. This oil can take away heat and create a good lubrication effect. At the same time, it increases the service life of the tool itself and improves the overall processing efficiency.

    Comprehensive advantage analysis

    IT6级铰削工艺_精密小孔铰削加工_镗削加工质量控制要点

    Compared with boring and milling, reaming has significant advantages in terms of efficiency and cost. It does not require complicated programming and multi-axis linkage, and requires relatively little investment in machine equipment. For the mass production of precision small holes, reaming is an extremely cost-effective solution. It can simplify the production process of the product, and at the same time, it can also ensure the consistency of the product.

    Reaming is particularly suitable for small hole finishing in soft materials such as mild steel and aluminum. Whether it is the breathing holes of mechanical equipment or the connecting holes of precision instruments, through reaming processing, you can obtain reliable accuracy guarantee. This is almost like performing an extremely delicate cosmetic surgery on the hole, making every detail the best.

    Summary of pit avoidance guide

    To do a good job in reaming, the first thing to understand is that it is not just a "re-expanding operation", because it is an extremely sophisticated and complex process. This process requires comprehensive consideration of many factors such as tools, parameters, cooling, etc. If you only perform the operation muddle-headedly based on experience, it is extremely easy to increase the rate of scraps and increase the cost of production input. This is really not worth the gain.

    Before carrying out the actual operation, the basic principles of reaming should be fully understood. For different working conditions, detailed and specific work instructions must be developed. Tool wear needs to be checked regularly, and failed tools need to be replaced in a timely manner. Only by understanding the principles and then carrying out the actual operation can we avoid those detours in boring processing quality control, what is the small round hole on the tool used for, and produce less wasted workpieces, thereby truly achieving the goal of high-efficiency and high-quality precision machining.

    In terms of precision machining, which one, reaming or boring, is more suitable for your production line? Welcome to leave a message to discuss, like and share more useful information!

  • Titanium Alloy Processing And High-temperature Alloy Processing In CNC Processing (titanium Alloy Processing Temperature)

    Titanium Alloy Processing And High-temperature Alloy Processing In CNC Processing (titanium Alloy Processing Temperature)

    Titanium alloy processing and high-temperature alloy processing in CNC processing (titanium alloy processing temperature)

    Difficult-to-machine metal properties

    Titanium alloy, which is high in strength and corrosion-resistant, is extremely troublesome during machining. Its thermal conductivity is low, and heat cannot escape during cutting, and it is easy to accumulate on the tool. This characteristic causes the tool to wear very quickly, and the tool will chip or break if you are not careful.

    On the other hand, high-temperature alloys exhibit stable performance under high-temperature conditions and high-pressure environments, but they have extremely high hardness. On the one hand, it has high plasticity, and on the other hand, it has high hardness. This situation makes the cutting process extremely difficult. Processing this type of material requires stronger cutting force, which poses a severe test to the rigidity and stability of the machine tool.

    Titanium alloy processing and high-temperature alloy processing in CNC processing (titanium alloy processing temperature) (Fig. 1)

    Be particular about tool selection

    Carbide cutting tools must be used to process titanium alloys, and ordinary cutting tools cannot withstand it at all. Cutting parameters need to be carefully adjusted to ensure efficiency while avoiding overheating. Tool coating is also critical. A good coating can reduce friction, extend service life, and reduce replacement frequency.

    It is necessary to choose tool materials that are resistant to high temperatures and bending for high-temperature alloy processing. High-speed cutting processes are usually more suitable, but the premise is that the tool must be wear-resistant enough. The cooling system must be powerful and can take away the cutting heat in time to prevent the tool from softening and failure under high temperature conditions, thereby ensuring machining accuracy.

    Cooling and lubrication is key

    钛合金CNC加工_钛合金加工与高温合金加工对比_高温合金CNC加工

    During the processing of titanium alloys, the coolant must not only have a cooling effect, but also have a lubricating effect. Adequate cooling that prevents burns on the workpiece surface reduces tool thermal cracking. The use of high-pressure internal cooling tools that can send coolant directly to the cutting edge will have better results and can also completely solve the problem of heat dissipation.

    Titanium alloy processing and high-temperature alloy processing in CNC processing (titanium alloy processing temperature) (Fig. 2)

    High-temperature alloys cannot be separated from an efficient cooling and lubrication system. The temperature in the cutting area is extremely high. Ordinary cooling cannot cope with this situation. Therefore, special cutting oil will form a protective film to reduce the phenomenon of tool sticking. Moreover, good chip removal design is also critical. It can prevent chip accumulation and avoid scratching the machined surface and thus affecting the smoothness.

    Process design must be reasonable

    As for titanium alloys, the cutting speed should not be too fast, and the feed rate should also be moderate. The layered cutting strategy can effectively control the deformation of titanium alloys, which can improve the dimensional accuracy. When programming, the smoothness of the tool path must be taken into consideration to prevent impact loads caused by sharp turns to protect the tool and machine tool.

    When processing high-temperature alloys, emphasis should be placed on continuity and stability, and intermittent cutting should be prevented to reduce thermal shock. A reasonable amount of back cutting can balance efficiency and tool life. For components with more complex structures, simulation operations need to be carried out to predict deformation and compensate for errors in advance to ensure that the final product can meet extremely stringent standards.

    Industry applications are very different

    Titanium alloy processing and high-temperature alloy processing in CNC processing (titanium alloy processing temperature) (Fig. 3)

    高温合金CNC加工_钛合金CNC加工_钛合金加工与高温合金加工对比

    Titanium alloys are widely used in aerospace structural parts and medical implants. They are indispensable in aircraft frames and engine compressor blades. In the biomedical field, because of their biocompatibility, they have become the material of choice for artificial joints, and market demand continues to grow steadily.

    The hot-end components of aerospace engines are mainly made of high-temperature alloys. Parts such as turbine blades and combustion chambers in extreme environments must use them. With the continuous development of aerospace technology, the demand for high-temperature-resistant materials has increased sharply. Such materials have higher processing thresholds and larger profit margins, and are the core field of high-end manufacturing.

    Choose a professional service provider

    There are two types of materials that can be processed, which greatly test the manufacturer's capabilities. Jiebri has a team of senior engineering and technical personnel. This team is very proficient in various difficult problems. They provide services throughout the entire process from design to final implementation to ensure that delivery can be completed with high precision. The rich case library proves its technical strength and is trustworthy.

    When dealing with complex orders, experience is crucial. Jiebaorui has been deeply involved in this industry for many years and has mastered a large number of exclusive process parameters. Whether it is small batch customization or mass production, it can provide the best solutions. The professional team can help customers avoid crises, reduce costs, and enhance competitiveness.

    What do you think is the most troublesome problem for you when processing these two difficult-to-process materials? Is it that the tool wears out too quickly, or that the surface quality cannot meet the required requirements? Please leave your comments in the comment area for discussion. Don’t forget to like and share it with more people in the same industry!

  • Research On The Relationship Between Machining Accuracy And Surface Roughness In CNC Aluminum Parts Processing (cnc Aluminum Parts Processing Cutting Parameter Table)

    Research On The Relationship Between Machining Accuracy And Surface Roughness In CNC Aluminum Parts Processing (cnc Aluminum Parts Processing Cutting Parameter Table)

    Research on the relationship between machining accuracy and surface roughness in CNC aluminum parts processing (cnc aluminum parts processing cutting parameter table)

    Surface roughness is an intuitive reflection of processing accuracy

    In CNC aluminum parts processing, the factors that affect the machining accuracy of CNC milling accuracy refer to the accuracy of the part size, and also include the accuracy of the shape and position of the part. The surface roughness describes the micro-geometric shape error of the part surface. The two do not exist independently. They are interconnected, interact, and have an impact. Once the machining accuracy becomes higher, the vibration during the cutting process will be smaller, and the tool runout will be smaller. In this way, This will naturally lead to lower surface roughness values. For example, when processing a drone casing, we controlled the tolerance within ±0.01mm. After final measurement, the surface roughness Ra value dropped from 3.2μm to 0.8μm.

    A common misunderstanding is that as long as the machine tool accuracy is improved, a smooth surface can be automatically obtained. In fact, the impact of machining accuracy on surface roughness has to be transmitted through many links such as cutting parameters, tool geometry, and cooling methods. In a practical case of a precision parts factory in Shenzhen, the relationship between machining accuracy and surface roughness in CNC aluminum parts processing was studied (cnc aluminum parts processing cutting parameter table). When the machine tool positioning accuracy was increased from 0.005mm to 0.002mm, With the optimized feed speed, the surface roughness of the aluminum part dropped directly from Ra1.6μm to Ra0.4μm, which shows that accuracy improvement is indeed an effective way to improve roughness, but it must work in conjunction with other process parameters.

    Research on the relationship between machining accuracy and surface roughness in CNC aluminum parts processing (cnc aluminum parts processing cutting parameters table) (Figure 1)

    Direct effect of cutting depth on surface roughness

    Cutting depth is an extremely important bridge for connecting machining accuracy and surface roughness. In the operation of CNC milling aluminum parts, as the depth of cutting becomes smaller, the squeezing and tearing effect of the tool on the surface of the workpiece will become lighter, so the height of the residual area will be lower. When the cutting depth is reduced from 0.5mm to 0.1mm, the surface roughness Ra value of 6061 aluminum alloy parts decreases from 2.0μm to 0.6μm. Experimental data reflect this situation. The reason for this is that a small depth of cut can reduce the fluctuation of cutting force, reduce the tool yielding phenomenon, and thereby improve the surface quality.

    There is a situation where the smaller the cutting depth is not the better. In tests carried out at an auto parts factory in Jiangsu and Zhejiang, when the cutting depth was reduced to 0.02mm, the surface roughness deteriorated, and the Ra value rose back to 1.2μm. The reason for this is that the cutting depth is too small, causing the tool to slip on the work-hardened layer, resulting in extrusion friction instead of normal cutting, which in turn causes surface tears and micro-cracks. Therefore, in the actual CNC aluminum parts processing process, the choice of cutting depth must be determined based on a combination of machine tool rigidity, tool edge radius and material properties. It is usually recommended to find the best balance point between 0.05mm and 0.3mm.

    CNC铣削精度影响因素_CNC铝件加工加工精度与表面粗糙度关系_铝件加工精度对表面粗糙度的影响

    Quantitative relationship between feed speed and surface roughness

    As one of the core parameters that affect CNC milling surface roughness, feed speed and machining accuracy have a direct quantitative relationship. According to cutting theory, the theoretical surface roughness Ra value is proportional to the square of the feed amount. When processing aluminum parts for precision medical equipment, we lowered the feed amount per tooth from 0.1mm to 0.03mm, and the surface roughness Ra value dropped from 1.8 μm to 0.5 μm, a reduction of approximately 72%. This is due to the small feed amount causing the cutting thickness of each tooth to decrease and the height of the residual area to decrease.

    Research on the relationship between machining accuracy and surface roughness in CNC aluminum parts processing (cnc aluminum parts processing cutting parameters table) (Figure 2)

    However, lowering the feed speed will extend the processing time, which in turn will lead to higher costs. In an actual situation at a CNC processing factory in Dongguan, in order to control the surface roughness of a batch of aviation aluminum parts from Ra1.6μm to Ra0.8μm, the feed speed was reduced from 3000mm/min to 1500mm/min, and the processing time of a single piece increased by 40%. For high-volume production, this adjustment needs to be carefully weighed. A reasonable approach is to first adjust the feed speed to the lower limit of the recommended range, and then combine finishing allowance control and tool selection to achieve a balance between accuracy and efficiency.

    Tool status determines the upper limit of surface quality

    For CNC aluminum parts processing, the sharpness of the tool and the angle of the geometric shape can directly play a decisive role in whether the surface roughness can achieve the expected purpose. Even for high-precision machine tools, once worn tools are used, it is impossible to achieve ideal surface quality. Tests conducted by a laboratory in 2023 show that if the wear amount of the tool flank increases from 0.1mm to 0.3mm, and the aluminum alloy is processed under this condition, the surface roughness Ra value will increase from 0.8μm to 2.5μm. The reason why such a result occurs is that passivated tools will induce stronger cutting forces and frictional heat, which will further intensify the plastic deformation of the material.

    Surface roughness is significantly affected by the tool radius. In the finishing stage, when using the same cutting parameters, using a tool with a corner radius of 0.4 mm will have a surface roughness 'Ra' value that is approximately 30% lower than using a tool with a corner radius of 0.2 mm. This is because large-radius tools can form a smoother cutting trajectory, thereby reducing the depth of tool marks. In the electronic equipment casing processing factory in Suzhou, engineers changed the finishing tool from two blades to four blades, and also increased the tool tip radius from 0.2mm to 0.5mm. As a result, the surface roughness was successfully controlled stably from Ra1.6μm to Ra0.4μm, and the yield rate was increased from 85% to 97%.

    Cooling lubrication protects surface integrity

    Research on the relationship between machining accuracy and surface roughness in CNC aluminum parts processing (cnc aluminum parts processing cutting parameters table) (Figure 3)

    CNC铝件加工加工精度与表面粗糙度关系_CNC铣削精度影响因素_铝件加工精度对表面粗糙度的影响

    What is often underestimated is the impact of cooling and lubrication methods on surface roughness in CNC milling. However, in fact it is closely related to the continuous maintenance of machining accuracy and the stable state of surface quality. During the processing of aluminum parts, the main functions of cutting fluid are to reduce the temperature generated during cutting, reduce the degree of tool wear, wash away the debris formed after cutting, and lubricate the cutting area. Data from an auto parts manufacturing plant shows that using emulsion for cooling has a surface roughness Ra value that is about 35% lower than dry cutting. The reason is that sufficient cooling can inhibit the formation of built-up edges and prevent hard particles from scratching the finished surface.

    When comparing different cooling methods, there are significant differences in the effects. In a factory in Shenzhen that specializes in 3C product shell processing, staff conducted a comparison of pouring cooling and minimum quantity lubrication. The target was the processing effect of 6061 aluminum alloy. After comparison, the results show that under the minimum quantity lubrication method, the surface roughness Ra value is 0.6μm, but under the pouring cooling method it is 0.8μm. It is obvious that the effect achieved by the minimum quantity lubrication method is better. The reason is that minimum quantity lubrication has significant characteristics. It can penetrate into the cutting area more efficiently and quickly, thereby effectively reducing friction and adhesion caused by friction. At the same time, it completely avoids vibration caused by the impact of a large amount of coolant on the processing area. Therefore, when faced with the choice of cooling method, it is necessary to match and find the most appropriate lubrication solution based on the specific stringent requirements of machining accuracy and the pre-set goals of surface roughness.

    Collaborative optimization of process parameters to achieve best results

    The relationship between machining accuracy and surface roughness is not a simple linear relationship, but requires collaborative optimization of process parameters to achieve the best coordination. In actual CNC aluminum parts processing, a common practice is to use rough machining, semi-finishing and finishing processes. Rough machining is mainly aimed at metal removal rate, allowing the surface roughness to be slightly larger; finishing machining focuses on controlling dimensional accuracy and surface quality. In a non-standard parts processing factory in Jiangsu, by adjusting the finishing allowance from 0.5mm to 0.2mm, reducing the feed speed and increasing the cooling effect, the surface roughness Ra value was reduced from 1.2μm to 0.3μm.

    The key point for parameter collaborative optimization is to achieve a balance between the four elements of cutting speed, feed, cutting depth and tool geometry. Take the processing operation of an object such as a smart robot shell. As an engineer, the value of the spindle speed is increased from the original 8000rpm to 12000rpm. At the same time, the feed rate, which reflects the speed of a certain operation, is reduced from 0.08mm/tooth to 0.04mm/tooth. In addition, the cutting depth value, which reflects the thickness of the material removed during processing, is reduced. The numerical range was reduced from 0.3mm to 0.15mm. The final result was that the surface roughness Ra value of the intelligent robot shell dropped from 1.0μm to 0.4μm, and its dimensional tolerance was stabilized within the numerical range of ±0.02mm. This shows that only by optimizing each parameter as a system can we achieve simultaneous improvements in machining accuracy and surface roughness.

    In actual production, which parameter do you usually adjust first to control surface roughness? Is it the feed speed or the cutting depth? You are welcome to share your experience in the comment area, like it and forward it so that more peers can see it.