ISO 3274:1996

Overview

ISO 3274:1996 - "Geometrical Product Specifications (GPS) - Surface texture: Profile method - Nominal characteristics of contact (stylus) instruments" defines the profiles and general structure of contact (stylus) instruments used for measuring surface roughness and waviness. This second-edition GPS standard replaces ISO 3274:1975 and ISO 1880:1979 and sets out the instrument properties that influence profile evaluation, enabling consistent and traceable surface texture measurement with profile meters and profile recorders.

Key topics and technical requirements

• Profiles and profile types: Definitions of traced, reference, total, primary and residual profiles that form the basis for profile evaluation.
• Stylus instrument architecture: Measurement loop, reference guide, drive unit, probe (pick-up), tracing element and stylus tip (nominally conical with a spherical tip).
• Metrological characteristics: Static and dynamic measuring forces, hysteresis, probe linearity deviation, measuring range, quantization (ADC) step, range-to-resolution ratio, and transmission function for sine waves.
• Profile transmission and filtering: Short-wave transmission limitation, vertical and horizontal profile transmission characteristics, and the requirement for phase-correct filtering (modern instruments use filters compliant with ISO 11562).
• Instrument outputs: Digital storage, data input/output, profile recording and parameter calculation for roughness and waviness according to GPS procedures.
• Practical considerations: Influence of guide deviations, measurement loop disturbances, and the effect of analog 2RC filters (historical) on phase shifts and certain parameters.

Applications

• Specifying and selecting stylus instruments (profile meters/recorders) for production quality control and laboratory metrology.
• Defining instrument characteristics that affect surface roughness and waviness measurement accuracy.
• Providing a common basis for instrument makers, calibration laboratories and users to assess conformity and measurement capability.
• Supporting digital profile processing and parameter calculation in compliance with GPS profile-method standards.

Who should use this standard

• Metrologists and calibration laboratories
• Surface texture and quality control engineers
• Instrument manufacturers and designers of profile meters and probes
• Standards committees and technical drawing/product-definition specialists involved in GPS

Related standards

• ISO 4287 & ISO 4288 (surface texture terms and assessment rules)
• ISO 11562 (phase-correct filters)
• ISO 5436 (calibration specimens for stylus instruments)
• ISO 12085 and ISO 13565 series (profile parameter and characterization methods)

ISO 3274 is a foundational GPS document for anyone working with contact profilometry, helping ensure consistent, accurate surface texture measurement across instruments and applications.