GB/T 45687-2025 "Test Method for Selecting Vertical Stirred Mills" is a method standard that provides the basis for selecting vertical stirred mill equipment for ultra-fine grinding operations in fields such as mining, metallurgy, building materials, and chemical industry. It systematically specifies the complete process from test conditions, method principles, equipment and instruments to test procedures, data processing, and report preparation. The standard aims to address the limitations of traditional selection methods by establishing a unified test method and forming a standard database to guide the selection of industrial models. Its core lies in calculating key indicators such as "specific power consumption of stirred mill tests" by comparing data from stirred mill tests with Bond ball mill work index tests. The main instruments involved in the tests include the vertical stirred mill test machine for grinding tests, the Bond ball mill for reference comparison, and the laser particle size analyzer for accurately analyzing product fineness.