KERADUR GYPSUM YELLOW C. KG.25

APPLICATIONS

Gypsum/ water ratio

Chalk to water ratio (by weight) 3.00:1

Water to chalk ratio (by weight) 32%

Gypsum/water mixing ratio (by weight) 100/33

Chemical properties

Chemical name

Calcium sulphate hemihydrate

Chemical composition CaSO4.1/2H2O

Setting parameters

Fluidity of the Vicat ring (cm) 20-26

Initial setting time (minutes) 20-25

Linear expansion (%) 0.16

Mechanical properties

Flexural strength (MPa) 10,8

Brinell Hardness (MPa) 144

Dry compressive strength (Mpa) 43,4

Pore volume (%) 23

Physical properties

Particle size (% weight retained) 0.04% at 200 μm Bulk density (g/cm³) 1200

The technical data outlined represent only typical figures. For more details, please contact Saint-Gobain Formula directly.

INSTRUCTIONS FOR USE

Matrix preparation: The preparation of the matrix is fundamental. The overhead mesh must be well fixed to the frame. The gap between each air pipes must be constant (~2 cm between each). The aerial mesh should be located ~ 2 cm from the working surface of the Gypsum Preparation The temperature of plaster and water should be as close as possible during processing, within the range of 15-20 ° C, since the temperatures of plaster and water affect the gripping behavior. Sprinkle evenly over the entire surface of the water and let it soak for approx. 2 minutes. Depending on the intensity of the mixer and the amount, the recommended mixing time is 6 - 12 minutes. Mixing can begin from the beginning of soaking. To avoid air dragging, it is recommended to mix under vacuum. The temperature of the mixture should be taken at the end of mixing. The best thing is to control the increase in pressure according to the increase in temperature. After pouring, a thermometer is inserted into the mold. Once the temperature has risen from 6 to 8 ° C, you can start the purging process. The pressure should be increased by 0.5 bar from every half minute to every minute. After reaching 5 bar, bleed until the mold is dry, for at least half an hour. Il processo di spurgo può essere interrotto quando si possono vedere aree asciutte in superficie (2 ore). Lo stampo deve essere indurito per almeno 12 ore.