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1

Applying rapid heating for controlling thermal displacement of CNC lathe

Than Van-The, Wang Chi-Chang, Ngo Thi-Thao, Guo Guan-Liang

Archive of Mechanical Engineering

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2022

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LXIX, nr 3

519--539

EN

Thermal error always exists in a machine tool and accounts for a large part of the total error in the machine. Thermal displacement in X-axis on a CNC lathe controlled based on a rapid heating system is presented in this paper. Positive Temperature Coefficient (PTC) heating plates are installed on the X-axis of the machine. A control temperature system is constructed for rapid heating which further helps the thermal displacement to quickly reach stability. The system then continuously maintains stable compensation of the thermal error. The presented rapid heating technique is simpler than the compensation of machine thermal errors by interference in the numerical control system. Results show that the steady state of the thermal displacement in the X-axis can be acquired in a shorter time. In addition, thermal errors in constant and varying working conditions could be significantly reduced above 80% and 60%, respectively, compared to those without using the rapid heating. Therefore, the proposed method has a high potential for application on the CNC lathe machine for improving its precision.

2

Rapid heating induced vibration of circular cylindrical shells with magnetostrictive functionally graded material

Hong C. C.

Archives of Civil and Mechanical Engineering

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2014

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Vol. 14, no. 4

710--720

EN

The vibration and transient response of rapid heating on inner surface of the functionally graded material (FGM) circular cylindrical shells with outer magnetostrictive layer is investigated and computed by using the generalized differential quadrature (GDQ) method. The effects of heat flux value, power law index value, environmental temperature value and control gain value on Terfenol-D FGM circular cylindrical shell subjected to two edges clamped condition due to the not very high temperature fluid rapidly flow into the circular cylindrical shells from one side to the end of axial length direction are analyzed. The higher amplitudes of displacement and thermal stress can be obtained under the higher rapid heat flux value. With suitable product of coil constant and control gain value can reduce the amplitudes of displacement and thermal stress into a smaller value. The displacement of Terfenol-D FGM circular cylindrical shell versus the Terfenol-D thickness is stable for all power law index values. The Terfenol-D FGM circular cylindrical shell can stand against the higher temperature of environment with some values of power law index under rapid heating.

3

Numeryczne modelowanie ultraszybkich elektrotermicznych procesów grzejnych

Wesołowski M., Wolf-Łysiak D.

Elektronika : konstrukcje, technologie, zastosowania

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2011

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Vol. 52, nr 7

158-161

PL

W niniejszym artykule scharakteryzowano modelowanie dynamicznych procesów grzejnych. Podano modele matematyczne oparte na klasycznym równaniu przewodzenia ciepła oraz na równaniu Vernotte'a, możliwe do wykorzystywania w analizie procesów elektrotermicznych. Zaprezentowano wyniki obliczeń modeli, uzyskane na podstawie opracowanego algorytmu bazującego na metodzie bilansów elementarnych. Porównanie rezultatów obliczeniowych umożliwiło ocenę zakresu stosowalności poszczególnych równań z zachowaniem wysokiej dokładności wyników obliczeniowych.

EN

The paper characterizes the modeling of dynamie heating processes. The mathematical models based on classical equations of heat conduction and Vernotte equation useful for analysis of thermal processes arę described. The results of modeling based on the method of elementary balances are presented. The comparison of the results of the calculations has enabled the evaluation of the range of applicability of the considered equations in respect to high accuracy of this calculations.