Do you know the process of removing metal burrs?
Burrs, people who have struggled in the metal industry must be no stranger to it. In the process of metal product processing, it is ubiquitous. No matter how advanced and sophisticated equipment you use, it will be born with the product. The so-called burr is mainly caused by the plastic deformation of the material and an extra iron chip generated at the processing edge of the material being processed, especially the material with good ductility or toughness, which is particularly prone to burrs. The burr problem is precisely the metal processing industry. One of the problems that engineers can't solve so far.
The types of burrs in metal processing mainly include flashing burrs, sharp burrs, splashes, etc., which are a type of prominent excess metal residue that does not meet product design requirements. As for this problem, there is no effective method to eliminate it in the production process, so in order to ensure the product design requirements, engineers have only worked on the subsequent removal. So far, different products for different products There are many methods and equipment for deburring.
In general, the methods of deburring can be divided into four categories.
Coarse (hard contact) cutting, grinding, file and doctor blade machining are included in this category.
Ordinary grade (soft contact): This category includes abrasive belt grinding, grinding, elastic grinding and polishing.
Precision grade (flexible contact): This category includes washing processing, electrochemical processing, electrolytic grinding, and rolling processing.
Ultra-precision (precision contact): This class includes abrasive flow deburring, magnetic grinding deburring, electrolytic deburring, thermal deburring, and dense radium strong ultrasonic deburring. Part processing accuracy.
When we choose the deburring method, we must consider many factors, such as the material properties of the part, the shape of the structure, the size and precision of the part, and especially pay attention to changes in surface roughness, dimensional tolerances, deformation, and residual stress.
Describe the magic effect of electrolytic deburring:
The so-called electrolytic deburring is a chemical deburring method, which can remove burrs after machining, grinding and stamping, and round or chamfer the sharp edges of metal parts.
An electrolytic processing method for removing burrs of metal parts by electrolytic action, English abbreviation ECD. The cathode of the tool (usually brass) is fixed and placed near the burr part of the workpiece with a certain gap (usually 0.3 to 1 mm). The conductive part of the tool cathode is aligned with the burr edge, and the other surface is covered with an insulating layer, so that the electrolysis is concentrated on the burr part. During processing, the cathode of the tool is connected to the negative pole of the DC power source, and the workpiece is connected to the positive pole of the DC power source. A low-pressure electrolyte (usually sodium nitrate or sodium chlorate aqueous solution) with a pressure of 0.1 to 0.3 MPa flows between the workpiece and the cathode. When the DC power is turned on, the burrs will be dissolved and removed by the anode, which will be taken away by the electrolyte.
The electrolyte is corrosive, and the workpiece should be cleaned and rust-proofed after deburring. Electrolytic deburring is suitable for removing the burrs of the hidden holes in the parts or the parts with complex shapes. The production efficiency is high, and the deburring time is generally only a few seconds to several tens of seconds. This method is commonly used for deburring of gears, splines, connecting rods, valve bodies, and crankshaft oil circuit orifices, as well as rounding of sharp corners. The disadvantage is that the vicinity of the burr of the part is also subject to electrolysis, and the surface will lose its original gloss, and even affect the dimensional accuracy.
Of course, in addition to electrolytic deburring, there are several special deburring methods:
First, the abrasive particles deburr
Abrasive flow processing technology (AFM) is a new finishing deburring process developed in the late 1970s abroad. This process is particularly suitable for burrs that have just entered the finishing stage, but for small and long holes and metal molds with bottoms that are not accessible. Not suitable for processing.
Second, magnetic grinding to deburr
This method originated in the former Soviet Union, Bulgaria, and other Eastern European countries in the 1960s, and in the mid-1980s, Japanese cars made in-depth research on its mechanism and applications.
During magnetic grinding, the workpiece is placed in a magnetic field formed by two magnetic poles, and a magnetic abrasive is placed in the gap between the workpiece and the magnetic pole. The abrasive is neatly aligned in the direction of the magnetic field line under the action of the magnetic field force, forming a soft and rigid magnetic grinding Brush, when the workpiece in the magnetic field of the rotating shaft for axial vibration, relative movement of the workpiece and the abrasive, the abrasive brush will grind the surface of the workpiece; magnetic grinding method can efficiently and quickly grind and deburr parts, suitable for Various materials, various sizes and various structures are a kind of finishing method with low investment, high efficiency, wide use and good quality. At present foreign countries can already grind and deburr internal and external surfaces of rotating bodies, flat-plate parts, gear teeth, complex profiles, etc., remove oxide scale on wires and wires, and clean printed circuit boards.
Third, thermal deburring
Thermal deburring (TED) is to burn off the burrs with the high temperature generated after the detonation of the mixed gas when the oxygen gas or oxygen is formed with natural gas. Oxygen and oxygen or natural gas and oxygen are passed into a closed container and ignited by a spark plug, so that the mixed gas releases a large amount of heat energy in an instantaneous detonation to remove burrs. However, after the workpiece is exploded, its oxidized powder will adhere to the surface of the workpiece and must be cleaned or pickled.
Fourth, dense radium strong ultrasonic deburring
The dense radium strong ultrasonic deburring technology is a popular deburring method that has become popular in recent years. The attached cleaning efficiency is 10 to 20 times that of ordinary ultrasonic cleaning machines. The agent can be completed in 5 to 15 minutes at the same time.
