From sport to health and finance, accuracy matters in almost every industry. The same goes for manufacturing sectors such as automobile, aviation and electronics – where small errors can have costly consequences. In fact, one study found the average cost associated with a mistake or downtime for UK manufacturers is £98,000.
It’s crucial, then, to have dependable equipment and parts that ensure consistent results. But imperfections still occur from time to time, which when working with metal parts, can lead to small, sharp impurities known as burrs.
These imperfections are typically small ridges or protrusions on smooth surfaces that create a practical need for deburring. Below, discover the key processes and factors that can create burrs, as well as the different deburring methods and why they’re important.
What causes a burr?
Burrs can arise from several different production processes that are designed to shape parts to a desired form.
Common machining processes that cause burrs include drilling, engraving, milling and turning. Cutting processes that leave burrs meanwhile include blanking, punching, laser or plasma cutting and shearing.
There are other contributing factors too though. The skill of the machine operator can reduce or increase the risk of burrs occurring, for example. The thickness and grade of the material in question – and therefore its workability – also influences the likelihood of burrs.
What are the different types of burr?
Not all burrs are built equal. The three main types are:
- Rollover burrs, which are small bits of curled up metal protruding from a surface
- Poisson burrs, which extend sideways from a workpiece when extra metal collects at the end
- Breakout burrs, which are swellings that appear as if they’re bursting out of a surface
The deburring process
As discussed, deburring is the process of removing these burrs and leaving behind a smooth metal part. But there are multiple ways to achieve this goal.
Manual deburring processes can be the quickest and cheapest, involving the use of tools such as files, sanders and brushes, as well as more specialist items like countersinks.
But much like some machining processes, the effectiveness of manual deburring depends on the skill of the user. This means results can be inconsistent, occasionally leading to greater expense – especially considering surging global prices for industrial metals – as deburring occurs close to the finishing stage.
Alternatively, mechanical deburring techniques include barrel tumbling, electrochemical and waterjet deburring, and the use of purpose-built deburring machines. Such solutions involve greater initial financial outlay but ensure a finishing consistency that’s crucial for large-scale production operations.
Why deburring is important
Deburring can be overlooked in some cases as it isn’t always seen to add value to production, yet still requires time and investment. But it’s a vital process in many industries – especially those where accuracy and finish is vital.
This is partly because visible blemishes reduce the aesthetic appeal of parts or finished products. But burrs can also hamper performance, leading to part damage and eventual failure, and poorer function over their lifespan. They can also prevent products complying with certain standards, as well as reducing the effectiveness of specialist coatings.
Burrs also pose a risk of injury to both workers involved in a product’s production and transport, as well as to the end user. Deburring reduces this risk by eliminating sharp edges that aren’t always easy to spot at first glance.
Have you encountered burrs when using products or materials in the workplace or at home?