2. Tutorial:Engineering metrology Topic: Measuring of surface parameters Prepared by: Ing. Pavel Rožek Projekt Anglicky v odborných předmětech, CZ.1.07/1.3.09/04.0002 je spolufinancován Evropským sociálním fondem a státním rozpočtem České republiky.

3. Measuring of surface parameters

4. In accordance with new conception of geometrical product specification, presently surface inequality devide and separate the unevenes as follows:  Surface roughness – factor with smallest pitch uneveness  Surface waviness  Surface shape – Factor with largest pitch uneveness determined by basic profile

5. Defines following geometrical parameters:  R (Roughness) – parameter calculated of roughness profile,  W (Waviness) – parameter calculated of waviness profile,  P (Profile) – parameter calculated of basic profile,

6.  Surface profile is line of intersection of the real surface of given plane.  Scanned profile is midpoint’s geometrical place of scanned point of given parameters.  Roughness profile is obtained from basic profile by suppression of long-wave components, it is the base for roughness parameters evaluation.  Filter profile is filter dividing profile components to long-wave and short-wave.

7.  Basic roughness length (lr) is length in axis direction x used for uneveness identification characterising evaluated roughness profile. It numerically equals to wavelength of profile filter roughness.  Evaluation length (ln) is length in axis direction x used for evaluation of considered profile. Evaluated length can contain one or more basic lengths.

8.  Average arithmetical tolerance of considered profile roughness (Ra) is arithmetic diameter of absolute ordinate values Z(x) in basic length range. Dividing line

9.  Total height of roughness profile (Rt) is sum of height (Zp) of the highest profile lug and depth (Zv) of the lowest profile roughness depression in the evaluated range. Basic length Evaluated length

10. Turning, milling Grinding, sparking Surface roughness Periodical surface (turning, milling…) Irregular surface (grinding, sparking…) Groves middle distance of roughness elements Arithmetic dividing value Maximal heigth of profilr roughness Limit wavelength Basic length Measured length Total length Point radius Digitalised distance Measuring conditions up to

11. abcdefg U„X“0,08-0,8Rz5Max.1,6 a – Upper data U or lower L of determined limit– requirements for surface quality can be given with one – sided or 2 – sided tolerance. b - Filter type „X“ – normalized filter is Gauss filter (ČSN EN ISO 11562) ground

12. c – Filtration window – limits wavelength range which are included into evaluation. Filters are characterised by limit wavelength value - cut-off. d – Profile and parameter – complete graphic sign enables usage of 3 normalised groups of texture surface parameters. e – Evaluated length – determined by basic length numbers. f – Interpretation of determined limit – rule 16 % or „max“ g – Limit value in micrometers.

13. Rule 16 %  For parameters specified by upper parameter limit (U ) surfaces are acceptable if value mentioned in production documents exceeds maximal 16 % of all measured values of chosen parameters.  For parameters specified by lower parameter limit (L ), surfaces are acceptable if values mentioned in production documents do not reach maximal 16 % of all measured values of chosen parameters. Maximum rule It provides that at requirements specifying the highest parameter values during control, any of measured parameters values on whole controlled surface can not exceed value mentioned in production documents.

14. What kinds of geometrical parameters does ČSN EN ISO 4287 standard define? R– W- P- Question 2: Explain terms:  Basic roughness length (lr),  Evaluation length (ln).

15.  BUMBÁLEK, Leoš. Kontrola a měření. 1. Praha: Informatorium, 2009. 205 s. ISBN 978-80-7333-072-9  Mahr, MINIKATALOG – VÝROBNÍ MĚŘICÍ TECHNIKA Translation:  www.seznam.cz www.seznam.cz  www.slovnik.cz www.slovnik.cz  JANATA, Petr. Handy slovník technický anglicko-český a česko- anglický. Plzeň: Nakladatelství Fraus, 2000. ISBN 80-7238-075-3  Lingea LEXIKON 5, Technický slovník anglicko-český a česko- anglický. 2010.