Common density forms:
1. Mold cavity density: This density is equal to the mass of the molding material divided by the volume of the molding mold cavity.
2. Forming density: The mass of the formed wet wheel blank divided by the volume of the wet wheel blank. The difference between the wet blank volume and the mold cavity volume is due to the rebound of the blank. The rebound of vitrified bond roll grinding wheels and good-performance binder blanks can be ignored, but for high-pressure molding, using non-aqueous binders, the blank has considerable rebound, which must be considered under normal circumstances.
3. Inorganic (green) molding density: This density is only applicable to the formula table. It is a purely theoretical expression. It is the (inorganic) density obtained by removing the flammable temporary binder (such as dextrin), pore former and water from the weight of the abrasive blank. When calculating the unit weight of vitrified bond roll grinding wheel, find the given inorganic molding density in the formula table. This density only includes the mass of abrasive and binder, and then add the mass of temporary binder, water and pore former. Finally, calculate the actual unit weight of vitrified bond roll grinding wheel.
The advantage of using inorganic molding density is that any changes in temporary binder and water content can be easily considered in the calculation, that is, the molding density that has an effect on the hardness of vitrified bond roll grinding wheel and the part that has no effect on it are separated.
4. Finished product density: the mass of the grinding tool divided by the volume of the grinding tool. The difference between the finished product density and the inorganic molding density depends on the burning loss of the binder clay mass, the burning loss of the abrasive mass and the volume change of the grinding tool body related to the formula. Except for the fine-grained and high-hardness vitrified bond roll grinding wheel, the weight loss and weight gain of the two offset each other, and the finished product density is roughly equal to the inorganic molding density.
