UMI achieves the highest plaster quality through Claudius Peters’ Kettle Indirect Calcination. This superior calcination process takes advantage of narrow particle size distribution (PSD) attributed to the advanced grinding equipment and increases product strength through kettle calcination.
Despite the similarity in setting time (614- minutes) with gypsum manufactured using the traditional rotary calcining process which employs direct firing, kettle plaster exhibits greater strength and lower water demand. The kettle calcination process is slower than flash calcination or rotary calcination and produces homogenous, well-shaped crystals that are lower in BET surface and have high grain stability. The well-shaped crystals and smaller surface area.