scope:

Purpose and scope of application

Form measuring Instruments serve the purpose to determine form- and position deviations e.g. deviations from roundness, straightness, parallelism etc.

This Guideline (VDI/VDE 2631, Part 1) describes the principles of form measuring techniques, in particular the prerequisites and boundary conditions to be met by measurements of the form characteristics "roundness" and "straightness" and the position characteristics "parallelism" and "orthogonality" which are to be derived from the combination of roundness and straightness measurement results. This Guideline applies only to Standard geometries.

Part 1 contains a survey of Instrument components which are important for the measuring process and of quantities which exert an influence on the results of a form measurement. Knowledge of these influence quantities is important for the defmition of reasonable rules of procedure for acceptance and periodic inspection of form measuring Instruments.

This Guideline is aimed at describing measuring methods and geometrical material measures (Standards) which enable the user of form measuring Instruments to obtain traceable, reproducible and comparable measurement results.