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1

The effect of valley depth on areal form removal in surface topography measurements

Podulka P.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2019

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Vol. 67, nr 2

391--400

EN

Surface topography assessments with valley exploration are of great importance. Two-process surfaces are often proposed for many combustion engines. One of the errors committed in surface topography measurements and analysis are those that occur during data processing. In this paper, improper areal form removal was taken into consideration for plateau-honed cylindrical surfaces with additionally burnished oil pockets. Usually, the reference plane is established by application of: fitting algorithms (e.g. cylindrical shape), polynomials, filters and other procedures. In many cases, the influence of the reference plane was not fully recognized during valley depth consideration. Moreover, the influence of areal form removal with edge-to-dimple and valley‑to-dimple distances was not precisely defined. In this research, commonly used algorithms for form separation in surface topography analysis were proposed for the applications being considered. The digital filter bandwidth was also specified for valley depth analysis. The distortion of edge‑located oil pockets was specified. It was assumed that application of robust techniques does not necessarily provide the desired results.

2

Analiza rozmieszczenia kieszeni olejowych w pomiarach struktury geometrycznej powierzchni

Podulka P.

Mechanik

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2018

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R. 91, nr 11

984--987

PL

W artykule przedstawiono wpływ rozmieszczenia kieszeni smarowych na eliminację błędu kształtu w pomiarach struktury geometrycznej powierzchni. Analizowano powierzchnie cylindrów po gładzeniu płaskowierzchołkowym, z dodatkowo wygniatanymi kieszeniami olejowymi. Wynikiem pracy było określenie wpływu rozmieszczenia wgłębień smarowych na parametry struktury geometrycznej powierzchni (według normy ISO 25178) po usunięciu błędu kształtu z wykorzystaniem popularnych algorytmów (takich jak: dopasowanie cylindra za pomocą metody najmniejszych kwadratów, aproksymacja wielomianowa n-tego stopnia, filtr odporny na błędy regresji Gaussa) i/lub innych procedur (takich jak filtracja tylko części nośnej powierzchni lub cyfrowe wypełnienie wgłębień).

EN

In this paper the influence of distribution of oil pockets on areal form removal in surface topography measurement was taken into consideration. Surface topography of plateau-honed cylinder liners with burnished oil pockets was analyzed. The effect of dimples distribution on surface topography parameters (from ISO 25178 standard) after form removal by commonly used algorithms (cylinder fitted by the least square method, polynomials of nth degree, robust Gaussian filter) and/or other procedures (plateau-part filtering method, digital extraction of valleys) was taken into account.

3

Wyodrębnianie wgłębień na powierzchniach cylindrycznych

Pawlus P., Podulka P., Dobrzański P.

Mechanik

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2016

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R. 89, nr 11

1700--1701

PL

W pracy przedstawiono metodę wyodrębniania szerokich wgłębień struktury geometrycznej. Wgłębienia zostały następnie wypełnione gładkim kształtem. Analizowano powierzchnie cylindrów silników spalinowych po gładzeniu płasko-wierzchołkowym zawierających dodatkowo wygniatane kieszenie smarowe. Badano parametry z normy ISO-25178.

EN

In this paper the method of extraction of wide valleys in surface topography measurement was presented. Deep valleys were then filled by a smooth shape. Surface topography of plateau-honed cylinder liners with burnished oil pockets was taken into consideration. Parameters from ISO-25178 standard were analysed.

4

Selection of reference plane by the least square fitting methods

Podulka P.

Advances in Science and Technology. Research Journal

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2016

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Vol. 10, nr 30

164--175

EN

There are many disadvantages affecting the accuracy of surface topography measurement and analysis. One of them are the errors obtained during data processing. Usually surface topographies of car engine parts are studied after form removal. Many algorithms and procedures were developed and suggested. However, the selection of reference plane with accordance to surface topography measurements of cylindrical elements was not fully recognized. In this paper least square fitting methods (cylinder, polynomial) and commercial filters (Gaussian filter, Gaussian regression filter and robust Gaussian regression filter) for areal form removal were compared and proposed. Three types of surfaces: cylinder liners after plateau-honing, plateau-honed cylinder liners with oil pockets created by burnishing techniques and turned piston skirts were analyzed. Distortion of surface topography parameters (from ISO 25178 standard) according to improper selection of reference plane was also taken into consideration. It was assumed that least square fitted cylinder plane gave better results for both of type cylinder liners according to commonly used algorithm. However, for piston skirt surfaces the obtained results were very similar. For least square polynomial fittings it was found that applied method for cylinder liners gave usually better robustness for scratches, valleys and dimples occurrence. For piston skirt surfaces better edge-filtering results were obtained. It was also recommended to analyse the Sk parameters for proper selection of reference plane in surface topography measurements.

5

The effect of reference plane on values of areal surface topography parameters from cylindrical elements

Podulka P., Dobrzański P., Pawlus P., Lenart A.

Metrology and Measurement Systems

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2014

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Vol. 21, nr 2

247--256

EN

In this paper distortion of surface topography measurement results by improper selection of the reference plane is taken into consideration. The following types of surfaces from cylindrical elements were analyzed: cylinder liners after plateau honing, cylinder liners with additionally burnished oil pockets and turned piston skirts. Surface topographies of these elements after a low wear process were also studied. In order to obtain areal surface topography parameters, the form was eliminated using cylinders and polynomials of the following degrees: 2, 3, 4, 6, 8, 10 and 12. Parameters of surfaces after form removal were compared. After analysis of results the reference elements for each kind of surface were recommended. A special procedure was proposed in order to select the degree of a polynomial. This method is based on surface topography changes with increase of polynomial degree. The effect of improper form elimination on measuring uncertainty was studied.

6

Modyfikacja filtru cyfrowego w odniesieniu do powierzchni zawierających szerokie wgłębienia

Pawlus P., Dobrzański P., Podulka P.

Mechanik

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2014

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R. 87, nr 8-9CD1

291-298

PL

Zaprezentowano propozycję filtru cyfrowego w zastosowaniu do powierzchni zawierających szerokie i głębokie wgłębienia. Ideą metody jest filtracja tylko części nośnej powierzchni, nie naruszając kształtu wgłębień. Przedmiotem badań były powierzchnie zawierające kieszenie smarowe wykonane metodą wygniatania oraz powierzchnie cylindrów po gładzeniu płasko-wierzchołkowym, mierzone profilometrem stykowym. Stwierdzono, że stosowanie proponowanej metody zapewnia poprawniejsze wyniki niż wykorzystanie filtru odpornego powodującego często zniekształcenia chropowatości powierzchni.

EN

This paper presents proposal of digital filter applied to surface containing wide and deep dimples. The idea of this method is filtering of only plateau surface portion without changing shape of deep valleys. Surfaces containing wide dimples after burnishing as well as plateau honed cylinder surfaces were analysed. It was found that the proposed method assures better results than application of robust filter.