Appearance changes

Discoloration: The surface color of copper bushing will change. Normal copper bushing is generally copper color, when burned, due to high temperature oxidation, the surface of copper bushing may become black, blue or dark brown. For example, in a high temperature environment, copper will react with oxygen to generate copper oxide, so that the surface color change.

Surface roughness: The surface of the burned copper bushing is no longer smooth, and there will be obvious wear marks, scratches or granular bumps after sintering. This is because under high temperature and abnormal friction, the material on the surface of the copper bushing is destroyed, and part of the copper may melt and then solidify, forming a rough surface.

Deformation: Copper bushings may show shape changes, such as localized expansion and distortion. This is due to the high temperature so that the internal structure of copper changes, resulting in the size and shape of the copper bushing changes. Especially in the case of localized high temperature of copper bushing, the uneven thermal expansion will cause deformation.

Performance degradation

Abnormal operation: During the operation of the equipment, if the copper bushing burns out, abnormal noise will be heard. This is because the fit between the copper bushing and the shaft becomes abnormal, producing vibration and friction sounds. For example, a motor that was running smoothly will make a harsh “buzzing” or “creaking” sound when the copper bushing burns out. At the same time, the running accuracy of the equipment will be reduced, jumping, swinging and other phenomena, affecting the normal work of the equipment.

Increased temperature: A burnt copper bushing generates a lot of heat, causing its own temperature to rise dramatically, and this high temperature will be transmitted to the surrounding components. An abnormal increase in temperature can be detected by touching the equipment shell (if touching is allowed) or by using equipment such as infrared thermometers. Generally speaking, the temperature of the copper bushing in normal operation will be within reasonable limits, whereas when it burns out, the temperature may be far above normal, and may even cause the surrounding lubricant to smoke or catch fire.