Loss of stability and energy of metallic vacuum membranes of sealing agents. Some technical systems operate in the presence of vacuum.
DOI:
https://doi.org/10.15276/opu.2.70.2024.03Keywords:
stability, deflection, energy level, membrane, loss of stability, equilibriumAbstract
Some technical systems operate in the presence of vacuum. To control the vacuum depth, vacuum control sensors are often used, which are rather complex and expensive electrical devices. The paper investigates the energy capabilities of metal membranes of vacuum closures, which, in the process of controlled loss of stability, can perform the function of vacuum sensors in packaging without the use of special sensors. Studies have shown that membranes stamped on the field of closures lose their stability due to pressure drop, and the shape is restored due to the transformation energy that occurs in them as a result of the loss of stability. The value of this energy depends on the thickness of the membrane. The parameters of the membranes of different tinplate thicknesses were obtained and the corresponding graphical dependencies were constructed. According to the research, with a decrease in the membrane thickness, the transformation energy increases, while the pressure of loss of stability decreases. In the process of digital modelling, it is proposed to estimate the level of internal energy of metal membranes by comparing the energy levels of different membranes in possible equilibrium states. The proposed method is based on the mathematical modelling of the energy levels of the membrane equilibrium state, performed using the energy method from the theory of plates and shells. The energy levels of membranes of different tinplate thicknesses in the state of loss of stability are obtained, each of which has its own minimum. Based on the results of digital modelling, the energy component was analysed and the minimum energy values during the loss of membrane stability were calculated for membranes of different thicknesses. It is shown that an energy jump occurs during the transition from one equilibrium state to another. During the energy jump, due to the release of the transformation energy, the membrane moves instantaneously in space. It is proposed to estimate the energy levels of metal membranes by the method, according to which the energy levels of different membranes in equilibrium states are compared.
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