Papers by Keyword: Deburring

Abstract: A novel edge treatment method that utilizes a tip-burnishing process with an active rotary tool developed by the authors was proposed. Two types of burnishing process experiments were conducted using the tip-burnishing process to deburr the workpiece edge and create a sharp cutting edge. Furthermore, an evaluation test for the cutting performance of the sharp edge, which was treated using the developed burnishing process, was conducted. In the deburring experiment, superior deburring was achieved by generating a sliding effect orthogonal to the burr generation direction. An experiment was conducted for evaluating the sharpening of the cutting edge; it was observed that the cutting-edge angle decreased due to the burnishing process. A cutting performance test was conducted using a wedge-shaped workpiece before and after burnishing. The cutting performance of the workpiece was quantitatively evaluated based on the load and stroke required for the cutting of the sheet material.

Abstract: The electrochemical machining technology has unique processing characteristics, often used to machining the hard material. But electrochemical techniques applied to carbon steel or heat treatment after the material processing, surface generates a black layer after the processing that is carbon-rich layer. This layer is the product of a non-electrochemical reaction of precipitation that hinder the process, leading to reduced rate of electrochemical machining and increasing the surface roughness of workpiece. This study presents electrochemical micromachining combine abrasive slurry injection ways to improve electrochemical machining black layer problem. In this thesis, the hollow tube is used in 500 and 700μm, and the NaCl is chosen as the electrolyte to drill SKD11, and investigate the influence of different voltage, concentration, abrasive concentration, and electrode gap.

Abstract: Blanks made from sheet steel or other materials have burrs on their edges. The burrs are formed on the blanks at cutting down or processing of them by cutting tools. Removing of the burrs requires a lot of manual work. Frequently the blanks have small rigidity, and it especially complicates removal of the burrs. This article describes intensification of the magnetic abrasive finishing method (MAF) with a goal to eliminate the manual deburring and to raise productivity of deburring on the flexible blanks. The study goal was achieved by optimization of MAF conditions and a of the work area geometrical form.

Abstract: After milling process burrs can form as a result of plastic deformation of the material. Wire brushing can be used as a fully automated method of deburring on machining centres. In order to provide the same effects after brush change it is important to precisely determine the tool diameter. The article presents the method of dynamic diameter determination of circular brushes, which is the diameter of the brush during rotation.

Abstract: In a large-area electron beam (EB) irradiation method developed recently, high energy EB can be obtained without focusing the beam, and large-area EB with almost uniform energy density distribution of 60mm in diameter can be used for instantly melting and evaporating metal surface. Then, the surface smoothing and surface modification of metal molds made of steel, cemented carbide and ceramics can be performed efficiently. When the large-area EB is irradiated to a sharp edge, the material removal remarkably progresses at the edge due to the heat accumulation and EB concentration there, which leads to the edge rounding. Our previous study clarified that micro-deburring was also possible by using this phenomenon. Moreover, this method would be effective for removal of discontinuous micro burrs generated by thermal machining processes, such as EDM and laser cutting. In this study, the possibility to completely remove micro burrs generated in EDM was experimentally investigated. The difference in micro-deburring characteristics with the type of workpiece material was also investigated. As a result, the EDM micro burrs with a height of about up to 50μm could be completely removed by this method. Furthermore, it was made clear that the magnetic property of workpiece materials greatly influenced the deburring characteristics, and the thermal property such as melting point and thermal conductivity also did.

Abstract: For weight reducing and functional reasons, hollow shafts should be used in gear units in the near future. Inside they have a big cylindrical cavity, which is only accessible through small inlet holes. This cavity may have large diameter variations along its length. There is an undesirable scale-formation, if high temperatures occur during the manufacturing process. If there are cross bores in areas, then there are also burrs in the area of cross bore section. While this area is oil flooded, it must be free of scale and burrs. Some mechanical tools and a thermal process are able to remove the burr in cross holes. The deburring could often be done over the transverse bore. Even small cross holes can be safely trimmed. A big problem is the removal of scale in difficult to reach hollow areas. With an innovative cutting tool it would be possible to remove the scale in difficult to reach areas. Measurement methods are shown, which would be automatically check if the surface is free of scales and burrs.

Abstract: Micro-abrasive water jet technology for deburring is a new type of removing burrs technics with advantages of high productivity, high flexibility, no cutter damage and less residual damage etc, which is applied more and more extensively. This paper introduces the difference of premixed micro-abrasive water jet and post-mixed micro-abrasive water jet on jet formation, the difference of system principles and applications. This paper also provides the formula that how to quantitatively calculate the impact force of water jet. The principles and factors which influence on deburring and some application examples are also described in this paper.

Abstract: The reason and harm of deburring in continuous casting machine, Based on the disk cutter type deburring technology in continuous casting machine system working principle and Application, The effect of deburring for the production practicek, And pointed out that in the process of debugging and operation of common breakdown and processing method.

Abstract: At present, crankshafts with larger size are finished mostly by abrasive cloth and manual steel brush, which is not ideal on finishing quality, efficiency and cost, especially cleanness degree does not meet design and use request. So horizontal spindle barrel finishing has been developed and has good finishing effects for crankshafts with small size. But this process has bad uniformity for connecting rod journal of crankshafts with larger size by simulation experiments. Aimed at the size, shape and weight of crankshafts with larger size, theoretic research is done, and main factors for finishing uniformity are analyzed. Finally its finishing project is defined and experiments are done. The research indicates that this process is very effective for crankshafts with larger size, and has also positive influence on efficiency and auto product line.

Abstract: In aircrafts, hydraulic systems control moveable parts. For example parts like the front strut or the landing flaps. These parts are usually made from aluminium or titanium. Due to an increasing number of functions these valves show an increasing number of cross holes. The production process causes burrs at the intersection of the holes. Until now these burrs cant be removed reliably by an automated process. Remaining burrs can influence dimensional tolerances and reduce the efficiency and technical lifetime of the component. In some applications cross holes are used for the lubricant and coolant supply. In this case burrs can lead to blockades of critical passages or cause turbulences in the fluid. This can lead to leakage or bursting of the valve. Hence an uncontrolled removal of the burr during operation must be avoided. The consequence of these basic conditions is a time consuming manual deburring process. An automated deburring process of cross holes with industrial robots is usually performed with flexible abrasive brushes. Alternatively processes like AFM (Abrasive Flow Machining), ECM (Electro Chemical Machining) or TEM (Thermal Energy Machining) are used. Those processes are very efficient but require specialized equipment and cleaning processes for the used chemicals and the remaining abrasive paste. So they are not suitable for the deburring of safety related parts. This paper presents an experimental based approach for the robot based deburring of cross holes using industrial robots. For the deburring of cross holes several special tools are available. This article gives a short overview over the specific advantages and disadvantages of these tools. As the investigations revealed the best results can be achieved using the so called Orbitool developed by JWDone. The Orbitool is a tungsten carbide cutter developed for the deburring of cross holes. A better control of the required dimension at the intersection compared to brushes and other deburring methods is possible. Furthermore the tool can be used on machine tools and industrial robots and is flexible to a huge variety of bore diameters. The tool mainly consists of a ball shaped carbide milling cutter with a protective disk which is made of polished steel and a shaft of tool steel. To remove the burr the tool is moved along the bore axis into the smallest of the intersecting holes until the tip of the tool is close to the intersection. Then the tool is moved in radial direction to the bore surface until the tool axis corresponds to the interpolation diameter. This causes a deflection of the tool. In this situation only the protective disk is in contact with the bore surface. While the tool rotates it is moved towards the intersection in a helical motion. When the tool tip has reached the intersection the cutting edges get in contact with intersection and the deburring process begins. After the tool has passed the whole intersection it stops its rotation and is moved to the bore hole centre and then moved out of the workpiece. This paper deals with the optimization of the deburring process. The result mainly depends on the parameters movement speed of the robot, slope of the helical movement and rotational speed of the tool. The experiments are planned using DOE (Design Of Experiment) methods. Initial values for the optimization of the movement speed were determined by grid encoder measurements. Robotic specific parameters like the number of interpolating points and the influence of the path smoothing caused by the controller were also investigated. For the analysis of the burr and the secondary burr an optical 3-D measurement system is used. The results show that with the presented approach the burrs can be reliably removed. Before the deburring process the average burr height is about 60 μm and can be reduced so that there is no secondary burr visible. The result is a chamfer between 150 μm and 85 μm that depends on the process parameters. It can be demonstrated that a chamfer that is smaller than 100 μm leads to a secondary burr. Anyway the cycle time can be reduced from about 3 minutes for manual deburring to 30 seconds using an industrial robot. Additional wear analysis show that about 200 bore holes can safely be deburred.