Burrs are everywhere in the metal processing process. No matter how advanced precision equipment you use, it will be born together with the product. It is mainly a kind of excess iron filings generated at the processing edge of the material to be processed due to the plastic deformation of the material. Especially materials with good ductility or toughness are particularly prone to burrs.
The main types of burrs include flash burrs, sharp corner burrs, spatter and other protruding excess metal residues that do not meet product design requirements. Regarding this problem, there is no effective method to eliminate it in the production process so far. Therefore, in order to ensure the design requirements of the product, engineers can only work hard on the removal of the back-end process. So far, different products have different requirements. There are many methods and equipment for removing burrs.
Xinfa CNC tools have the characteristics of good quality and low price. For details, please visit:
CNC Tools Manufacturers – China CNC Tools Factory & Suppliers (xinfatools.com)
Generally speaking, burr removal methods can be divided into four categories:
1. Coarse level (hard contact)
Belonging to this category are cutting, grinding, filing and scraper processing.
2. Ordinary level (soft touch)
Belonging to this category are belt grinding, grinding, elastic wheel grinding and polishing.
3. Precision level (flexible contact)
Belonging to this category are flushing processing, electrochemical processing, electrolytic grinding and rolling processing.
4. Ultra-precision level (precision contact)
Belonging to this category are abrasive flow deburring, magnetic grinding deburring, electrolytic deburring, thermal deburring and dense radium powerful ultrasonic deburring, etc. This type of deburring method can obtain sufficient part processing accuracy.
When we choose a deburring method, we must consider many factors, such as the material characteristics of the part, structural shape, size and precision. In particular, we must pay attention to changes in surface roughness, dimensional tolerances, deformation, and residual stress.
The so-called electrolytic deburring is a chemical deburring method. It can remove burrs after machining, grinding and stamping, and round or chamfer the sharp edges of metal parts.
An electrolytic processing method that uses electrolysis to remove burrs from metal parts, referred to as ECD in English. Fix the tool cathode (usually made of brass) near the burr part of the workpiece, with a certain gap (usually 0.3 to 1 mm) between them. The conductive part of the tool cathode is aligned with the burr edge, and the other surfaces are covered with an insulating layer to concentrate the electrolysis on the burr part.
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 to 0.3 MPa flows between the workpiece and the cathode. When the DC power supply is turned on, the burrs will dissolve in the anode and be removed, and will be taken away by the electrolyte.
The electrolyte is corrosive to a certain extent, and the workpiece should be cleaned and rust-proofed after deburring. Electrolytic deburring is suitable for removing burrs from cross holes in hidden parts or parts with complex shapes. It has high production efficiency and 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 openings, as well as sharp corner rounding, etc. The disadvantage is that the parts near the burrs are also affected by electrolysis, and the surface will lose its original luster and even affect the dimensional accuracy.
Of course, in addition to electrolytic burr removal, there are also the following special burr removal methods:
1. Abrasive flow deburring
Abrasive flow machining technology (AFM) is a new finishing and deburring process developed abroad in the late 1970s. This process is particularly suitable for burrs that have just entered the finishing stage, but it is not suitable for small and long holes and metal molds with blocked bottoms. etc. are not suitable for processing.
2. Magnetic grinding and deburring
This method originated in the former Soviet Union, Bulgaria and other Eastern European countries in the 1960s. In the mid-1980s, Japanese manufacturers conducted in-depth research on its mechanism and application.
During magnetic grinding, the workpiece is placed into the magnetic field formed by two magnetic poles, and magnetic abrasives are placed in the gap between the workpiece and the magnetic poles. The abrasives are neatly arranged along the direction of the magnetic lines under the action of the magnetic field force, forming a soft and rigid magnetic grinding machine. Brush, when the workpiece rotates and vibrates axially in the magnetic field, the workpiece and the abrasive move relative to each other, and the abrasive brush grinds the surface of the workpiece; the magnetic grinding method can grind and deburr parts efficiently and quickly, and is suitable for It is a finishing method with low investment, high efficiency, wide application and good quality for parts made of various materials, sizes and structures.
At present, foreign countries can grind and deburr the internal and external surfaces of the rotating body, flat parts, gear teeth, complex surfaces, etc., remove the oxide scale on the wires, and clean the printed circuit boards, etc.
3. Thermal deburring
Thermal deburring (TED) uses the high temperature generated by the deflagration of the mixture of hydrogen and oxygen gas or oxygen and natural gas to burn off the burrs. It is to pass oxygen and oxygen or natural gas and oxygen into a closed container, and ignite it through a spark plug, so that the mixture explodes in an instant and releases a large amount of heat energy to remove burrs. However, after the workpiece undergoes explosive combustion, its oxidized powder will adhere to the surface of the workpiece and must be cleaned or pickled.
4. MiLa powerful ultrasonic deburring
MiLa powerful ultrasonic deburring technology is a deburring method that has become popular in recent years. The cleaning efficiency alone is 10 to 20 times that of ordinary ultrasonic cleaning machines. The holes are evenly distributed in the water tank, eliminating the need for ultrasonic cleaning. The dosage can be completed simultaneously within 5 to 15 minutes.
We have compiled the 10 most common deburring methods for everyone:
1) Manual deburring
This is also a method commonly used by general enterprises, using files, sandpaper, grinding heads, etc. as auxiliary tools. The files have manual filing and pneumatic shifting.
Brief comment: The labor cost is expensive, the efficiency is not very high, and it is difficult to remove complex cross holes. The technical requirements for workers are not very high, and it is suitable for products with small burrs and simple product structures.
2) Die deburring
Use a die and a punch to remove burrs.
Brief comment: A certain punching die (rough die + fine punching die) production fee is required, and a shaping die may also be required. It is suitable for products with relatively simple parting surfaces, and the efficiency and deburring effect are better than manual work.
3) Grinding and deburring
This type of deburring includes vibration, sandblasting, roller and other methods, which are currently used by many companies.
Brief comment: There is a problem that the removal is not very clean, and it may be necessary to manually deal with the remaining burrs or use other methods to remove burrs. Suitable for small products with larger batches.
4) Frozen deburring
Use cooling to quickly embrittle the burrs, and then spray projectiles to remove the burrs.
Brief comment: The equipment price is about 20,000 to 300,000 yuan; it is suitable for products with small burr wall thickness and small products.
5) Hot blast deburring
It is also called thermal deburring and explosion deburring. By passing some flammable gas into an equipment furnace, and then through the action of some media and conditions, the gas explodes instantly, and the energy generated by the explosion is used to dissolve and remove burrs.
Brief comment: The equipment is expensive (prices in the millions), requires high operating skills, has low efficiency, and has side effects (rust, deformation); it is mainly used in some high-precision parts fields, such as automotive and aerospace precision parts.
6) Engraving machine deburring
Brief comment: The equipment is not very expensive (tens of thousands), and is suitable for applications where the space structure is simple and the required deburring locations are simple and regular.
7) Chemical deburring
Using the principle of electrochemical reaction, parts made of metal materials can be automatically and selectively deburred.
Brief comment: It is suitable for internal burrs that are difficult to remove, and is suitable for small burrs (thickness less than 7 wires) on pump bodies, valve bodies and other products.
8) Electrolytic deburring
An electrolytic machining method that uses electrolysis to remove burrs from metal parts.
Brief comment: The electrolyte is corrosive to a certain extent, and the parts near the burrs are also affected by electrolysis. The surface will lose its original luster and even affect the dimensional accuracy. The workpiece should be cleaned and rust-proofed after deburring. Electrolytic deburring is suitable for removing burrs from cross holes in hidden parts or parts with complex shapes. It has high production efficiency and the deburring time generally only takes a few seconds to tens of seconds. It is suitable for deburring gears, connecting rods, valve bodies and crankshaft oil passage openings, as well as sharp corner rounding, etc.
9) High pressure water jet deburring
Using water as a medium, its instantaneous impact force can be used to remove burrs and flash generated after processing, and at the same time achieve the purpose of cleaning.
Brief comment: The equipment is expensive and is mainly used in the heart of automobiles and the hydraulic control system of construction machinery.
10) Ultrasonic deburring
Ultrasonic waves generate instantaneous high pressure to remove burrs.
Brief comment: Mainly for some microscopic burrs. Generally, if the burrs need to be observed with a microscope, you can try to use ultrasonic method to remove them.
Post time: Nov-16-2023
