The document describes a problem with a transport system where wood-based material is transported through a pipe using water. After a month of operation, the pipe was found to be leaking. The cause was determined to be the material rubbing and knocking against the inside of the pipe, damaging it and causing water to leak. The pipe and transportation medium (water) cannot be changed and the operating method must remain the same. TRIZ 40 design principles could be used to resolve the engineering contradiction and find potential solutions that allow material to be transported without interrupting operations or causing further pipe leaks.