What is waviness height in surface finish requirements?

Waviness height is defined as the measurement of the tallest point from a mean line across a surface. This concept is crucial in surface finish requirements because it indicates the overall form deviations that can occur over longer distances compared to roughness, which pertains to finer deviations. Waviness can affect the functional performance of a part, such as sealing, friction, and wear properties, making it an important aspect for engineers to consider during the manufacturing process.

Understanding this definition situates waviness within the broader context of surface finish characteristics that include roughness and lay, where waviness is characterized by more significant variations that can arise from factors like machining conditions and tool wear.