Common methods for deburring

Shanghai deburring machine manufacturer introduces common methods for deburring.

Although the burr is not big, it directly affects the quality of the product. So with the increasing emphasis on deburring in various industries, deburring methods have emerged one after another. There are several commonly used trimming/deburring methods:

manual

conventional; And edge trimming knives have gradually replaced these traditional methods, without the need for technical processing, saving costs and being environmentally friendly.

Chemistry

Using the principle of electrochemical reaction, deburring operations are automatically and selectively performed on parts made of metal materials. It can be widely used for deburring parts such as pump bodies, valve bodies, connecting rods, plunger needle valves, and other components made of different metal materials in industries such as pneumatic, hydraulic, engineering machinery, oil nozzle pumps, automobiles, and engines. Suitable for parts with internal burrs that are difficult to remove, heat-treated, and precision machined.

electrolysis

ECD is an electrochemical machining method that uses electrolysis to remove burrs from metal parts. Fix the tool cathode (usually made of brass) near the burrs on the workpiece, with a certain gap (usually 0.3-1 mm) between them. The conductive part of the tool cathode is aligned with the edge of the burr, and the other surface is covered with an insulation layer to concentrate the electrolytic action on the burr. During processing, the cathode of the tool is connected to the negative pole of the DC power supply, and the workpiece is connected to the positive pole of the DC power supply. A low-pressure electrolyte (usually sodium nitrate or sodium chlorate aqueous solution) with a pressure of 0.1-0.3 megapascals flows between the workpiece and the cathode. After connecting to the DC power supply, burrs are removed by anodic dissolution and carried away by the electrolyte. The electrolyte has a certain degree of corrosiveness, and the workpiece should be cleaned and rust proofed after deburring. Electrolytic deburring is suitable for removing burrs from hidden cross holes or complex shaped parts in parts, with high production efficiency. The deburring time generally only takes a few seconds to tens of seconds. This method is commonly used for deburring gears, splines, connecting rods, valve bodies, and crankshaft oil passage holes, as well as rounding sharp corners. The disadvantage is that the vicinity of burrs on the parts is also subjected to electrolytic action, causing the surface to lose its original luster and even affecting dimensional accuracy.

ultrasonic

When the ultrasonic energy generated by ultrasound is applied to a liquid that is vibrating in a sparse state, it will tear into small cavities (i.e., the interior is vacuum). These cavities will generate instantaneous pressures of up to several hundred atmospheres when they rupture, and this phenomenon is called cavitation. Ultrasonic deburring is the process of using the instantaneous impact force of hundreds of atmospheres generated by the "cavitation phenomenon" to remove burrs attached to components. Ultrasonic deburring is not suitable for all burrs, mainly for some microscopic burrs. Generally, if burrs need to be observed with a microscope, ultrasonic methods can be tried to remove them. For visible burrs, it mainly depends on the strength of the bonding. For burrs with weak bonding strength, ultrasonic waves can be used. For burrs that can only be treated with cutting tools, ultrasonic methods are simply not feasible. The advantages and disadvantages of ultrasonic deburring.

High pressure water jet

As the name suggests, it uses water as a medium and utilizes its instantaneous impact force to remove burrs and burrs generated after processing, while also achieving the purpose of cleaning. After multiple experimental tests, a suitable pressure range of 30MPA-50MPa was found. If the pressure is insufficient, the deburring effect cannot be achieved. Although excessive pressure can remove burrs, there is a risk of damaging the workpiece. Usually, hydraulic components are subjected to a liquid pressure of less than 20MPa during use. The residual burrs that cannot be removed even with a pressure of 50MPa have a very small chance of falling off at a working pressure of several megapascals. It can also be considered that the residual burrs at the root of the workpiece are part of the workpiece. There are more and more manufacturers of high-pressure water deburring equipment, which can be summarized into two categories: workpiece moving and nozzle moving. The mobile workpiece has low cost and is suitable for deburring and cleaning simple valve bodies. Its disadvantage is that the fit between the nozzle and the valve body is not ideal, and the deburring effect of the cross holes and inclined holes inside the valve body is not good; The nozzle moving type can effectively adjust the distance between the nozzle and the burr generating part of the valve body through CNC control, effectively corresponding to the burrs of the cross holes, inclined holes, and blind holes inside the valve body. However, due to the high cost of this equipment, only the heart of the car and the hydraulic control system of engineering machinery can generally enjoy this favor.