Burr (edge)
![](http://upload.wikimedia.org/wikipedia/commons/thumb/8/8b/Metal_burr.jpg/220px-Metal_burr.jpg)
A burr is a raised edge or small piece of material that remains attached to a
In the printmaking technique of drypoint, burr, which gives a rich fuzzy quality to the engraved line, is highly desirable—the great problem with the drypoint medium is that the burr rapidly diminishes after as few as ten impressions are printed.
Types
There are three types of burrs that can be formed from machining operations: Poisson burr, rollover burr, and breakout burr. The rollover burr is the most common.[2] Burrs may be classified by the physical manner of formation. Plastic deformation of material includes lateral flow (Poisson burr), bending (rollover burr), and tearing of material from the workpiece (tear burr). Solidification or redeposition of material results in a recast bead. Incomplete cutoff of material causes a cutoff projection.[3]
Burrs can be minimized or prevented by considering materials, function, shape, and processing in the design and manufacturing engineering phases of product development.[3]
Burrs in drilled holes cause fastener and material problems. Burrs cause more stress to be concentrated at the edges of holes, decreasing resistance to fracture and shortening fatigue life. They interfere with the seating of fasteners, causing damage to fastener or the assembly itself. Cracks caused by stress and strain can result in material failure. Burrs in holes also increase the risk of corrosion, which may be due to variations in the thickness of coatings on a rougher surface. Sharp corners tend to concentrate electrical charge, increasing the risk of static discharge. Burrs in moving parts increase unwanted friction and heat. Rough surfaces also result in problems with lubrication, as wear is increased at the interfaces of parts. This makes it necessary to replace them more frequently. Electrical charge buildup can cause corrosion.[4]
Deburring
![](http://upload.wikimedia.org/wikipedia/commons/thumb/0/03/Deburring_tool.jpg/60px-Deburring_tool.jpg)
There are many deburring processes, but the most common are
Manual
Manual deburring is the most common deburring process because it is the most flexible process. It also only requires low cost tools and allows for instant inspection.[6] Manual deburring is either done with tools like scrapers, files, sandpaper, stones and reamers or with handheld power tools that use abrasive points, sandpaper, or cutters similar to those used to deburr during machining.
Electrochemical
Electrochemical deburring is the use of
Thermal
Thermal energy method (TEM), also known as thermal deburring, is a deburring process used to remove hard-to-reach burrs or burrs from multiple surfaces at the same time. The process uses an explosive gas mixture to provide thermal energy to burn off the burrs. It is the fastest burr removal process, requiring only 20 milliseconds to remove a burr.[7]
The process starts by loading the workpiece into an
Cryogenic
Cryogenic deburring is a
Mechanical
![](http://upload.wikimedia.org/wikipedia/commons/thumb/e/e2/Mechanical_Deburring_Tool.jpg/220px-Mechanical_Deburring_Tool.jpg)
Mechanical deburring is a deburring process that either mechanically grinds a burr off of metal or rolls the edge of the dangerous slit or sheared metal burrs into itself. Rolled mechanical deburring was first developed in the 1960s by Walter W. Gauer from Gauer Metal Product, Inc.[10] as a means to speed up the process of hand deburring strips of metal that were used in bakery racks.[11]
Water jet
One of the main benefits of waterjet deburring is a high level of precision and repeatability - and for this reason, CNC control is used. This eco-friendly process uses high-pressure water to remove loose burrs and chips even in deep holes – all while leaving the parts cleaner and free of debris. Pressurized water is precisely focused via CNC control to remove burrs and chips in and around parts. Depending on the cleanliness specifications, this can be performed submerged or in an open-air environment. Open-air washing/deburring targets specific areas of the part where the water jet is focused. Submerged will clean the entire part, internally and externally. [12]
Ultrasonic Deburring
Powerful ultrasonic waves are irradiated against the tank containing the liquid. This technology removes burrs by the pressure generated within the liquid as cavities are generated and dissipated.
See also
References
- ^ Gillespie 1999, p. 1.
- ISBN 978-1-315-36031-7.
- ^ a b Tool and Manufacturing Engineers Handbook (TMEH), Volume 3, Materials, Finishing and Coating. Society of Manufacturing Engineers, 1985.
- ^ Davidson, David. "Surface Condition Impacts Part Performance," Metal Finishing, February 2007.
- ^ Gillespie 1999, pp. 7–11.
- ^ a b Gillespie 1999, p. 11.
- ^ ISBN 978-0-8247-7352-6.
- ^ Gillespie 1999, pp. 195–196.
- ^ "Deburring Services | Nitrofreeze". 25 April 2012.
- ^ Schultz, Dennis. "Gauer Edging Machines". Gauer Edging Machines.
- ^ Metal Progress, Volume 96
- ^ Campbell, Andrea (2022-05-04). "15 Benefits of CNC-Controlled High Pressure Deburring & Parts Cleaning". Sugino Corp. Retrieved 2022-10-10.
Bibliography
- Gillespie, LaRoux K. (1999), Deburring and edge finishing handbook, SME, ISBN 978-0-87263-501-2.
- Warfield, Bob (2018), Definitive Guide to Deburring for CNC, CNCCookbook.