Sulphoaluminate cement mainly includes three varieties: fast hardening calcium sulphoaluminate cement, low alkalinity calcium sulphoaluminate cement and self stressing calcium sulphoaluminate cement.
Fast hardening calcium sulphoaluminate cement is made of calcium sulphoaluminate cement clinker, 5% ~ 15% anhydrite or dihydrate gypsum and no more than 15% ~ 35% limestone. This kind of cement has the characteristics of early strength, fast hardening and chemical corrosion resistance. It is mainly used in cement products and concrete engineering of industrial and civil buildings. Especially in rush repair, need to resist seawater erosion and winter construction, it can reflect the superiority of this kind of cement.
Low alkalinity calcium sulphoaluminate cement consists of calcium sulphoaluminate cement clinker, 5% ~ 20% anhydrite and 15% ~ 35% limestone. This kind of cement is characterized by early strength, rapid hardening and low alkalinity (pH value of hydration liquid is lower than 10.5). It is mainly used in the production of glass fiber reinforced cement products.
Self stressing calcium sulphoaluminate cement is made by grinding sulphoaluminate cement clinker, 30% ~ 40% dihydrate gypsum and no more than 15% limestone. The cement is characterized by high expansion during hydration and hardening, which is mainly used to produce cement pressure pipe.