Which patch material cannot be used to isolate a ruptured pipe?

• A. Rubber patch
• B. EWARP
• C. Duct tape
• D. Metal plate

Answer: (B)

Patching a ruptured pipe means creating a seal that will hold under the system’s pressure long enough to stop the flow temporarily and allow further repairs. While many patches can seal leaks, emergency weld repair patches are designed to overlay the leak and cure to form a seal, not to provide a standalone mechanical shutoff. Because of that, EWARP patches rely on curing and adhesion and may not guarantee a solid, pressure-proof isolation by themselves, especially on larger or high-pressure ruptures. In contrast, a rubber patch or a metal plate, secured properly, provides a more immediate and reliable mechanical seal to stop flow. Duct tape is not a dependable solution for pressure piping either, but the key idea is that EWARP doesn’t function as a definitive isolating method on its own, which is why it’s not used to isolate a ruptured pipe in this context.