Gypsum powder for making chalks - PYTF006

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_{Use for making chalks}

Manufacturing Process

The main raw material of making chalk are calcium carbonate and plaster of paris , calcium carbonate can be instead of YAG powder, the more can reduce costs. YAG powder has two kinds ofproduction method: dry grinding & polishing with a waterstone,polishing powder in water made chalk for beautiful. In the past the break extremely easily and made chalk consumption also is very big, the reason is adding water into gypsum to making chalks simply, not join calcium carbonate. Now the general formula for manufacturing chalk: calcium carbonate (or YAG powder) 4, and gypsum 8 (or 6), water 10 ratios. The first step of making chalks is mix the calcium carbonate and plaster of paris, add water into the thin slurry, and then quickly poured into the metal model coated with oil (common for olive oil or flame like) each hole , about ten minutes or half an hour after all solidification, the model can be dismantled, take out and dry in the sun.