The method and characteristics of the rotation molding
The rotation molding is commonly known as the blank, also known as the plate knife molding. This molding method is to form rotating gypsum molds and model knives to form rough blank. During the operation, the mud that is practiced by the vacuum mud training machine is made into a mud ball and puts it into the plaster mold, then plaster molds are made in the rotating mold seat, and then the knife is slowly pressed down. With the rotation of the model, the mud is forced to unfold on the working surface of the gypsum model. The excess mud is discharged along the mold through the form of a cutter. Therefore, the shape of the knife mouth and the shape of the model work surface constitute the shape of the inner and outer surface of the blank parts. The gap between the model working surface and the knife mouth is filled by the mud to form the thickness of the blank parts.
The rotation molding is divided into internal and external rotation. The gypsum mold used in the inner rotation is concave, and the shape of the inner wall is the shape of the blank body, and the shape of the edge of the knife mouth is the surface shape of the blank body. This kind of rotation method is also known as yin model molding. The gypsum mold used by the outer rotation, the inner surface of the blank depends on the protruding shape of the model, and the outer surface of the blank body is pressed out of the knife. This method of rotation, also known as yang model. According to the characteristics of porcelain, the wares such as bowls, cups, and soups should be used to use yin -molded blanks. The plate flat utensils are generally adopted by yang mold blanks, but there are also internal rotation forming.
The advantage of rotating molding is that the equipment is the equipment, which is strong and can be pressed out of large or deep products. However, because the positive pressure of the model knife to the mud is small, the molding moisture of the mud is high, so the structure of the body is not uniform, resulting in poor density, and the deformation rate of the product is higher than that of rolling.