Inspection Of Bubble Defects After Shrinkage Of Pre-insulated Bushing

After shrinkage is complete, a systematic inspection of the surface and internal condition of pre insulated sleeve is required. The presence of air bubbles is a key point, as any internal gas or voids may have a potential impact on subsequent performance. Air bubbles are often caused by the material's inherent quality or uneven heat distribution during the shrinkage process. They can appear as noticeable protrusions or depressions and may also create tiny internal voids. The presence of these voids is closely related to material properties and processing conditions.

Workers typically use magnified visual inspection, optical testing instruments, or specific non-destructive testing equipment to inspect the shrunken pre insulated junction sleeve. During the inspection, attention is focused on the surface and edge areas, as these are where discontinuities are most likely to occur. For thicker or opaque insulated joint sleeve, non-destructive ultrasonic testing or other methods can be combined to identify potential internal voids from the outside. This inspection process is similar to defect detection for other industrial components.