Abstract: Disclosed is a method for pre-detecting a defective porous polymer substrate for a separator, including selecting a porous polymer substrate having a plurality of pores; observing the selected porous polymer substrate with a scanning electron microscope (SEM) to obtain an image of the porous polymer substrate; quantifying the average value of pore distribution index (PDI); correcting the quantified average value of pore distribution index to obtain the corrected average value of pore distribution index; determining whether or not the corrected average value of pore distribution index is 60 a.u. (arbitrary unit) or less; and classifying the porous polymer substrate as a good product, when the corrected average value of pore distribution index is determined to be 60 a.u. or less, and classifying the porous polymer substrate as a defective product, when the corrected average value of pore distribution index is determined to be larger than 60 a.u.

Abstract: A method and a system for cooling a steel strip are disclosed. A high water volume mist cooler and a low water volume mist cooler are disposed along a direction in which the steel strip travels. The high water volume mist cooler sprays high water volume mists onto the surfaces of the steel strip to cool the steel strip, and then the low water volume mist cooler sprays low water volume mists onto the surfaces of the steel strip to cool the steel strip, thereby cooling the steel strip while suppressing the influence of transition boiling, to prevent the steel strip from having a temperature-nonuniform portion.

Abstract: A method and a system for cooling a steel strip are disclosed. A high water volume mist cooler and a low water volume mist cooler are disposed along a direction in which the steel strip travels. The high water volume mist cooler sprays high water volume mists onto the surfaces of the steel strip to cool the steel strip, and then the low water volume mist cooler sprays low water volume mists onto the surfaces of the steel strip to cool the steel strip, thereby cooling the steel strip while suppressing the influence of transition boiling, to prevent the steel strip from having a temperature-nonuniform portion.

Abstract: A method and a system for cooling a steel strip are disclosed. A high water volume mist cooler and a low water volume mist cooler are disposed along a direction in which the steel strip travels. The high water volume mist cooler sprays high water volume mists onto the surfaces of the steel strip to cool the steel strip, and then the low water volume mist cooler sprays low water volume mists onto the surfaces of the steel strip to cool the steel strip, thereby cooling the steel strip while suppressing the influence of transition boiling, to prevent the steel strip from having a temperature-nonuniform portion.

Abstract: A method and a system for cooling a steel strip are disclosed. A high water volume mist cooler and a low water volume mist cooler are disposed along a direction in which the steel strip travels. The high water volume mist cooler sprays high water volume mists onto the surfaces of the steel strip to cool the steel strip, and then the low water volume mist cooler sprays low water volume mists onto the surfaces of the steel strip to cool the steel strip, thereby cooling the steel strip while suppressing the influence of transition boiling, to prevent the steel strip from having a temperature-nonuniform portion.

Abstract: A method and a system for cooling a steel strip are disclosed. A high water volume mist cooler and a low water volume mist cooler are disposed along a direction in which the steel strip travels. The high water volume mist cooler sprays high water volume mists onto the surfaces of the steel strip to cool the steel strip, and then the low water volume mist cooler sprays low water volume mists onto the surfaces of the steel strip to cool the steel strip, thereby cooling the steel strip while suppressing the influence of transition boiling, to prevent the steel strip from having a temperature-nonuniform portion.