Meaning of Deburring: What is understood by the term "deburring"?

• Deburring metal workpieces is a challenging but indispensable process step in production. If not deburred, the quality and function of the workpiece will suffer.
• Burrs are a byproduct of machining operations. The most difficult burrs to remove are often located on the internal bore edges or back sides of workpieces.
• Various methods and processes for deburring bores exist, which are selected depending on the materials and the required results.

Deburring plays a crucial role in many industries, including metal, wood, and plastics processing. This report focuses on metal-working industries such as Automotive, Aerospace, or also pneumatics.

But what exactly is deburring? Deburring involves removing splinters or chips, so-called burrs, from the sharp edge or surface of the workpiece. This not only affects the appearance of the workpiece but, above all, its functionality and safety. Depending on the material of the component, different methods are necessary.

How are burrs formed? We will look at this aspect in the next section.

Various factors influence the size and form of the burr. These include the type of machining (e.g., excessive feed rates), the condition of the tool used (e.g., unsharpened blade), incorrect machine settings, and the material of the workpiece. There are ways to avoid or reduce the formation of burrs. This includes using high-quality tools.

There are numerous reasons why the burr must be removed from the workpiece. We will consider these in the next section.

If burrs are not removed, the functionality of the workpiece can be impaired, or problems can arise in further processing. It is possible that the part will no longer fit with other components or that the efficiency of the finished product will be reduced.

Furthermore, the burr poses a safety risk or an injury risk for the operator. If burrs are not properly removed, sharp edges can lead to cuts for the user. To minimize the risk of injury, it is therefore essential to properly deburr sharp bore edges.

Thirdly, we mention the aesthetics of the component, which are affected.

Now that we understand the reasons, let's look at the different methods for deburring.

For deburring metal, there are various processes and methods that are used depending on the situation and requirements. First, a choice must be made between removing burrs from external edges, holes, or surfaces. For each type of deviation, there are specific processes, e.g., interpolation, tumbling, or step drilling.

Deburring processes for holes include:

• Manual Deburring
• Mechanical Deburring
• Thermal Deburring (TEM)
• Electrochemical Deburring (ECM)
• High-Pressure Waterjet Deburring
• Abrasive Blasting with Granules
• Brush Deburring

We will examine these methods in more detail below.

Manual Deburring

Manual deburring is the most common method for removing burrs. It is done in a manual operation and is used particularly for individual parts or small series. The operator of the deburring tools needs a high degree of concentration and manual skills. It is a simple, flexible method for small batch sizes and low-quality requirements, but it also has some disadvantages:

• Deburring by hand is very time-consuming
• High costs for large series
• Quality deviations, irregular work results
• High risk of injury for the operator

Thermal Deburring (TEM)

In thermal deburring (TEM), the material to be removed is vaporized by the high heat generated by a chemical reaction. TEM is used particularly for complex geometries, hard-to-reach areas, or when there are many bores. External and internal sharp edges are deburred simultaneously in the process. Almost all oxidizing materials can be processed. The result is sharp-edged or slightly rounded bore edges. The size of the deburring chamber limits the workpiece size or quantity. The influence of heat on the material and the geometry of the component must be checked.

Electrochemical Deburring (ECM)

In electrochemical deburring (ECM), burr removal is achieved by the anodic dissolution of metal. It is used for almost all metals, even for hardened workpieces. Since it is a contactless process with very low heat input, there is no tool wear, no formation of secondary burrs, and no mechanical stress. The maximum burr length is limited to approximately 0.3 mm. The metal part must be thoroughly cleaned before and after treatment.

High-Pressure Waterjet Deburring

In high-pressure waterjet deburring, multiple edges and hard-to-reach bores are deburred simultaneously. A water jet is directed at the areas of the component to be processed at a pressure of up to 1,000 bar. It must be checked whether particles are dislodged from the bore edge due to mechanical stress and whether rough surfaces are created due to the only partial removal of burr flags.

Abrasive Blasting with Granules

In abrasive blasting with granules, materials such as sand are directed at the bore edge at speeds of up to 80 m/s. Adjacent areas are also affected. Cleaning after deburring can be a challenge.

Brush Deburring

In brush deburring, burrs on the workpiece are removed by special brush tools. Handling is simple and the range of applications is diverse due to the variety of tool variants. Limits for brush deburring are larger burrs, very hard materials, and hard-to-reach areas.

HEULE develops and produces tool solutions exclusively for mechanical deburring with a defined cutting edge. This technology offers numerous advantages over alternative methods such as interpolation, brushing, step drills, electrochemical deburring, or manual deburring.

1. Increased Process Reliability: Better quality through consistent deburring results
2. Cost Savings: Low quality control costs, reduced logistics effort, lower investment costs
3. Reduced Error Risk: Elimination of manual interventions such as reclamping the workpiece
4. Lead Time Gain: Automated in-house process and elimination of externally performed deburring operations
5. Lower Machine Occupancy: More efficient deburring creates free machine capacity and lower investment needs
6. Satisfied Employees: Simple and safe handling of tools during maintenance, commissioning, and operation

HEULE offers various options for removing burrs. There are tools for different bore diameters, but also for parts with cross bores. If desired, tools are also individually adapted or developed.

COFA: From bore Ø 2.0 mm: Front and back deburring of even and uneven bores in one operation

DL2: Bore Ø 1.0 mm to Ø 2.1 mm: Front and back deburring of even and slightly uneven bores in one operation

X-BORES: Custom solutions for deburring intersecting bores, so-called cross bores

Solutions for your specific application: Your application scenario is not covered? We are happy to advise you and develop a solution tailored to your application.

The field of application for mechanical deburring tools in practice is large. Particularly in the production of large series, direct integration into the CNC machine is in high demand, as this reduces process times and greatly increases process reliability.

HEULE's customers include big names from the following industries: Automotive, Aerospace, Mechanical and Plant Engineering, Transport, Medical Technology. Typical parts have hard-to-reach bore edges or challenging geometries. Classic examples include fork pieces, crankshafts, or also alloy wheels.

Often, existing manufacturing methods in industry are replaced by mechanical deburring. The customer benefits from burr-free edges, leading to improvements in process times and process reliability.

In summary, it can be stated that metal parts in industry usually need to be deburred after manufacturing. On the one hand for quality reasons, on the other hand for safety reasons. For deburring, there exist various methods that are used depending on the situation and requirements. The correct choice of deburring method is crucial, as this has a significant influence on the quality of the result and process reliability.