BAV-090: Silicone Spacers for Vacuum Box Lap weld Inspection

Vacuum box leak testing of tank bottom welds is a very common application.
Tank bottom plates are typically lap welded, meaning one plate is placed over the other. During assembly, it’s not uncommon to encounter joints with double overlaps, resulting in additional thickness at certain weld intersections. Since the plates themselves can be 8 to 10 mm thick, leak testing may sometimes involve lap weld nodes with a total offset of up to 25 mm.

The sealing and interface foams used in vacuum boxes need to be flexible—but no matter how soft the foam is, it cannot perfectly conform to a sharp 90° angle without either manual assistance or filling the gap created by the foam’s curvature. In practice, it’s not unusual to see inspectors using whatever is available—gloves, wet cloths, or plastic bags—to fill these voids and ensure proper sealing.

To provide a simple and reliable solution to this issue, we’ve developed an innovative silicone spacers system, specifically designed to make leak testing in these complex configurations extremely easy and efficient.