How does surface finish of pipes influence friction losses?

The surface finish of pipes plays a significant role in influencing friction losses due to its impact on how fluid flows along the pipe's interior. A rough surface can create turbulence and increase the resistance that the fluid encounters as it moves through the pipe. This increased resistance is characterized by higher friction losses.

When the surface of a pipe is smooth, the fluid can flow more easily, experiencing less resistance and consequently lower friction losses. In contrast, a rough or poorly finished surface increases turbulence, which leads to higher friction as the fluid interacts more with the irregularities of the pipe wall.

Understanding this concept is essential for millwrights when selecting pipe materials and finishes for specific applications, as minimizing friction losses can lead to increased efficiency in fluid transport systems. Consequently, the correct answer highlights that surface finish significantly influences friction losses by increasing them when the surface is rough.