Zastosowanie metod statystycznych do monitorowania procesu obróbki elektroerozyjnej elektrodą drutową

• Autorzy: Nowakowski A. , Majerski P.

Warianty tytułu

EN

Application of statistical methods in the monitoring of the EDM machining with wire electrode

• Konferencja: Międzynarodowa Konferencja Naukowo-Techniczna EM'12 (Electromachining) (11 ; 16-18.05.2012 ; Bydgoszcz-Pieczyska, Polska)
• Języki publikacji: PL

Abstrakty

PL

Dla potrzeb monitorowania procesów wycinania i mikrowycinania elektroerozyjnego opracowano modele statystyczne wykorzystujące mechanizm średniej kroczącej. W przypadku wycinania średnia krocząca opisuje proces zmian wartości czasu opóźnienia wyładowań. Przy mikrowycinaniu średnia krocząca śledzi proces ewolucji wybranych trzech typów impulsów napięcia międzyelektrodowego. Przedstawione metody mogą być wykorzystane zarówno do kontroli przebiegu procesów WEDM jak i mikro-WEDM. Modele zweryfikowano w trybie off-line, wykorzystując zrejestrowane ciągi impulsów napięcia międzyelektrodowego oraz podczas obróbki, implementując go w mikroprocesorowych analizatorach procesu.

EN

The paper presents investigations of the WEDM and micro-WEDM processes degeneration, carried out with MEDIOS-20 and the experimental micro-WEDM machine MW50 type developed in IZTW. The measuring stand consisted of the WEDM machines connected with the gap voltage pulses analysers, the data logger, the PC computer with the dedicated software for data acquisition and processing. The main tool used for prediction of the both processes degeneration was the moving average (MA) model, endowed with a parameter q, which plays a role of a smoothing parameter as well as a 'memory' window. During the WEDM machining the subject of the analysis was the delay time of discharges. In the micro-WEDM process the data input for the model was the transient numerical time series received from the gap voltage discriminating system, which separated the gap voltage pulses into three classes: idle, normal and short, according to their amplitude before discharge and the voltage drop during discharge. During the analysis it has been observed, that very often the MA for the degenerated processes decreased just before the wire braking, whereas this almost never happened for the stable one. Algorithms calculated the on-line process degradation level (WZ) were derived from the above model. The off-line verification of the presented models, performed with the registered data, showed their good reliability. The algorithm was both applied in a microprocessor controller and verified on-line during the machining.

Słowa kluczowe

PL

średnia krocząca; proces losowy; elektroda drutowa; WEDM; mikro-EDM

EN

rolling average; random process; electrode wire; WEDM; micro-EDM

• Wydawca: Wydawnictwo Wrocławskiej Rady FSNT NOT
• Czasopismo: Inżynieria Maszyn
• Rocznik: 2011
• Tom: R. 16, z. 3
• Strony: 24--31
• Opis fizyczny: Bibliogr. 14 poz.

Twórcy

autor

Nowakowski A.

autor

Majerski P.

• Instytut Zawansowanych Technologii Wytwarzania, Kraków

Bibliografia

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