The work aims to analyze the energy consumption model of continuous heating thermal sealing process of thermal sealing equipment, and optimize intermittent heating thermal sealing process suitable for large-scale thermal sealing equipment. Firstly, the temperature rise and fall rule of nichchromium (Ni-Cr) alloy were studied by electric heating characteristic test, and the temperature rise and fall model of Ni-Cr alloy was obtained by fitting. Secondly, an energy consumption model of continuous heating thermal sealing process was analyzed, and an intermittent heating thermal sealing process suitable for large-scale thermal sealing equipment was proposed and an energy consumption model was established. With multi-layer PET/PE composite membrane as the thermal sealing object, and the optimal thermal sealing process was calculated with the minimum energy consumption as the optimization objective. The results show that the energy loss of large-scale thermal sealing equipment can be reduced effectively with the intermittent heating thermal sealing process.