## Clay Preparation Methods Clay materials were later combined with manual sieving and water hammering refinement. This combination of mechanical and manual methods improved production efficiency to a certain degree. In 1959, the Raymond pulverizer was introduced into the crushing process of zisha ore materials, achieving mechanization of ore crushing and sieving. This greatly improved work efficiency and reduced the harm of dust to the human body. Electric stone wheel grinding → Stone mill crushing → Electric mill crushing → Hammering clay materials ## Vacuum Clay Processing In 1966, the Zisha Craft Factory introduced vacuum clay mixing machines from fine ceramics production. Through mechanical mixing, stirring, preparation, and extrusion degassing of clay materials, this not only eliminated the low productivity of manual clay pounding, but also solved the problem of the long aging cycle of traditional "soil cultivation" clay materials, greatly shortening the clay refining process.