The metal sleeve is made according to the drawing, the dimensions are checked, but when installed, it unexpectedly gets stuck in the landing hole. The reason may be a tiny protrusion of metal on the edge, which is almost invisible without magnification. Similar defects occur in various machining processes, including brass milling, drilling, and turning. Moreover, even a burr several hundredths of a millimeter high can disrupt the operation of the exact connection.
The most annoying thing is that the problem does not always appear immediately. Sometimes the mechanism is successfully assembled, and the damage is detected only after several hours of operation.
Where do the burrs come from
During machining, the cutting tool separates the metal layer from the workpiece. However, at the exit of the material, the edge sometimes does not completely cut off, but plastically deforms and forms a thin protrusion.
Especially often such defects occur near holes, grooves and at the intersection of treated surfaces.
Their education is influenced by:
- Material properties. Ductile metals tend to stretch at the edges instead of cleanly separating the chips.
- The condition of the instrument. A worn cutting edge deforms the metal more strongly.
- Processing modes. Improper feed and exit trajectory of the tool can increase the size of the burr.
Even with the right settings, it is not always possible to completely eliminate their appearance. Therefore, deburring is often provided as a separate technological operation.
Why does a small protrusion interfere with the assembly
Imagine a shaft that must rotate freely inside the sleeve. If a metal protrusion remains on the edge of the hole, it may touch the surface of the shaft.
In the best case, the collector will have to make an extra effort. In the worst case, there will be scuffles, and the damaged connection will begin to wear out quickly.
Burrs can also cause other problems.:
- Violation of landing. The protrusion prevents the mating surfaces from fitting properly.
- Damage to the seals. A sharp edge can cut the rubber ring during installation.
- Ingress of chips into the mechanism. A broken fragment can end up between moving elements.
Loose metal particles in hydraulic systems are especially dangerous. They can clog narrow channels and damage the working surfaces of valves.
Where is the defect most dangerous
Not every burr is equally critical. On the outer edge of the decorative panel, a small protrusion is more often dangerous when touched. And inside
