A Burr is an unwanted material piece that remains attached to the main work piece after some sort of processing work, typically drilling or grinding. This extraneous material must be removed to continue work through a process called deburring, using a deburring tool. This type of work is often done by hand, adding additional time and expense to the production process.
Burrs can be found in any sort of material, including plastics and metals. Good candidates for deburring include parts to be assembled, since the burrs interfere with the seating of fasteners, the proper fit of seals and general smooth functioning. They can contribute to unwanted heat buildup, increase friction and contribute to the early failure of components. Deburring is also wise for any parts that will be handled, since the burrs create sharp edges that could cause injury.
In the design phase, the necessity of deburring as a finishing step should be kept in mind, and time left in the manufacturing cycle for this work to be done. Most deburring is done manually, but there are several specialized processes that can be used when this is not practical due to the quantity, type or inaccessible nature of the burrs. Electrochemical deburring uses a salt or glycol solution plus electricity to dissolve the burr in hard-to-reach or precision work pieces. The thermal energy method can remove multiple burrs in a very short time, using an explosive gas mixture to burn them away, while cryogenic deburring tumbles small parts in a very cold environment, causing the burrs to become brittle and more easily removed.
Manual deburring work is generally done as part of the standard finishing process on the assembly line. Specialized companies are equipped to handle the more complex processes or to do large quantities of deburring work. All of these companies will provide deburring quotes on request, and will provide samples of their work to aid in the decision making process.