Definitions

Manufacturing processes do not only change suddenly as in the case of tool breakage, but also gradually due to wear effects, machine malfunctions that occur over time, changes in material strength or lubrication conditions. This does not always lead to defective parts, but one should keep an eye on the development.

Trend monitoring measures and controls how the process signals change over time and whether limits are exceeded. Easily adjustable upper and lower trend limits ensure that the process cannot move away more than allowed from the start level.

Modern process monitoring systems use trend monitoring and display the measurement results in a clear graphic. Trend monitoring limits a possible drift and secures the production process against unwanted "wandering away".