Types and uses of construction gypsum

The most commonly used type of gypsum in construction is construction gypsum, followed by model gypsum. In addition, there are high-strength gypsum, anhydrous gypsum cement and flooring. plaster.

The raw material for producing gypsum is mainly natural dihydrate gypsum, also known as soft gypsum or raw gypsum, which is calcium sulfate containing two crystal waters. Natural dihydrate gypsum can be used to produce gypsum of various properties.

The main processes for producing gypsum are heating and grinding. Due to different heating temperatures and methods, gypsum with different properties can be produced.

(l) Building gypsum

Building gypsum is a white product made by calcining mature gypsum and other raw materials such as natural H-hydrate gypsum at a temperature of 107°C to 170°C, and then grinding it finely. Powder. Its main component is b-type hemihydrate gypsum.

After hardening, building gypsum has good thermal insulation and sound-absorbing properties and good fire-proof and moisture-absorbing properties; it is white in color and can be used for indoor painting construction, and is especially suitable for making various materials. White, smooth and delicate floral decoration, if you add pigments, the products can have various colors.

Construction gypsum is not suitable for outdoor projects and high-temperature projects above 65°C.

In short, construction gypsum can be used for indoor painting, making decorative products, porous gypsum products and gypsum boards, etc.

(2) Plaster of paris produced by calcining dihydrate gypsum of model gypsum. If the impurity content is small and the SKI is whiter and the powder is finer, it is called model gypsum. It sets faster than construction plaster and is stronger. Mainly used for making models, sculptures, decorative flowers, etc.

(3) High-strength gypsum is produced by placing H-hydrate gypsum in a pressure steamer and steaming it at 1.3 atmospheric pressure (124°C). Type A semi-hydrated gypsum has high strength after being ground finely. This gypsum has high density and strength after hardening. High-strength gypsum is suitable for plastering projects, decorative products and gypsum boards with high strength requirements. After incorporating a waterproofing agent, its products can be used in environments with high humidity. It can also be added to organic solution to form a binder.

(4) Anhydrous gypsum cement

When natural dihydrate gypsum is heated to 400℃~750℃, the gypsum will completely lose water and become insoluble anhydrite. After mixing and grinding an appropriate amount of activator, it becomes anhydrous gypsum cement. Anhydrous gypsum cement is suitable for indoor use, mainly used to make gypsum boards or other products, and can also be used for indoor plastering.

(5) Floor gypsum

If natural dihydrate gypsum is calcined above 800°C, part of the calcium sulfate will decompose into calcium oxide, and the finely ground product is called high-temperature calcined gypsum. , also known as floor plaster. After hardening, floor gypsum has high strength, wear resistance, and good water resistance, so it is mainly used as gypsum flooring and indoor floor decoration.

Hope it helps you~~~