What is BS EN ISO 4287:2016?

BS EN ISO 4287:2016 is an international standard that defines the parameters and measurement techniques for evaluating surface texture using contact (stylus) instruments. The standard provides a structured framework for assessing various aspects of surface texture, including roughness, waviness, and primary profile. By establishing guidelines for measurement, it ensures consistency and accuracy in the characterization of surfaces.

Understanding Surface Texture

Surface texture refers to the fine irregularities and deviations present on the surface of an object, which are not noticeable to the naked eye but can have significant implications for functionality and performance. It plays a critical role in determining the interactions between components in various applications, such as friction, wear, sealing, and appearance.

Roughness, Waviness, and Primary Profile

BS EN ISO 4287:2016 defines three main parameters for analyzing surface texture: roughness, waviness, and primary profile. Roughness represents the finest irregularities on the surface and is quantified by measuring the vertical deviations within a small sampling length. Waviness corresponds to mid-range irregularities and has a longer wavelength compared to roughness. Primary profile denotes the general shape and trend of the surface over a much larger sampling length.

Measuring Surface Texture

To measure surface texture according to BS EN ISO 4287:2016, a contact (stylus) instrument is used. The stylus traverses the surface following a specific path, collecting data points along the way. These data points are then processed to calculate the relevant parameters, such as roughness average (Ra) and peak-to-valley height (Rz). Accuracy and repeatability are crucial in surface texture measurement, as even small deviations can impact the functional performance of a component.