Stability testing methods in addition to the test cake method, as well as Reye clamp method and length measurement method. Although the latter two methods have a quantitative value limit, but the method complicated, complex play is also poor; and trial law cake with simple equipment, easy operation, sensitive, and direct observation, the complex play of good range of benefits, so far still as a national standard methods. Lian boiling cooking method can only detect the damaging effects of free calcium oxide. Since the fire burned more slowly than magnesium oxide, calcium oxide hydration rate, hence the boiling cooking method can not find insecurities caused by the magnesium oxide, only by autoclave test temperature, high pressure, in order to determine this phenomenon. The insecurities caused by sulfur trioxide, only cold bread method, immersion method can be tested, about to try cake in water after curing 28d 20 ℃ ± 3 ℃, checks whether there is instability phenomenon. Because when the temperature exceeds 60 ~ 70 ℃, it will not form a volume expansion generated sulphoaluminate. In home decoration, floor tiles, wall tiles paste, and so on to be used in cement mortar masonry cement block, which can only enhance the adsorption capacity of the surface material and the grass-roots level, but also to protect the internal structure, but can be used as the matte side leveling buildings layer, so the renovation works in grade cement, cement mortar material is essential. Many customers believe that the greater the total mortar cement ratio, the stronger its adhesion, it is often used in much the cement and decoration company divided. In fact, to paste tiles, for example, if the label is too large cement mortar, cement mortar setting when cement, cement absorbs moisture, then the tile water absorption of the surface layer is excessively easy crack and shorten life. Cement generally should cement: sand = 1: 2 (volume ratio) to stirring. Cement grade, Wuhan Cement (certified), Jiangsu cement provided by the Hongshan District of Wuhan pavilion cement operation. Hongshan District of Wuhan pavilion cement business unit (www.whltsn.com) (www.hbltsn.com) was Wuhan, cement and products leader, over the years, the company is implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, the maximum Limits to meet customer needs. Wuhan cement leadership with the staff warmly welcome all inquiries negotiations to create a better future Wuhan cement.