In recent years, with the development of the national economy, magnesia cementitious materials has been an unprecedented development of commodity. At present, magnesia cementitious materials raw materials (magnesium chloride, Magnesium Sulfate and Magnesium Oxide factory production of light burned) there are nearly 200. The magnesia cementitious materials products factory production of nearly 2000, the product involves magnesium duct, glass magnesium plate, glass magnesium board, all kinds of paper filling or hollow wall, arts and crafts, grinding head, packing box, vegetable greenhouse frame and a tail cover, (including fire door plate and the core plate, inorganic, furniture) cable channel such as dozens of categories, hundreds of kinds of specifications, in the formation of a real industry.
Because the magnesia cementitious materials industry low starting point, non national leading industry, in the development is completely free style. Although there are now dozens of the country has the appropriate size of the production company, but the overall is still a workshop based company, and the general existence of commodity quality control is not in place. There are financial factors, but also some of the appropriate companies do not know where to begin to control the quality of goods.
Magnesium Oxide company produces control points and control measures: whether mine is still buying ore from Magnesium Oxide production company, the first point is that the uniformity of ore control, the same batch should be the same for deposits or more occurrences according to the composition of collocation, primary control method is Magnesium Oxide, determination of calcium oxide by acid leaching method the. Second control points for the calcination of particle size. The existing baking furnace is difficult to achieve, only with the pre heating and suspension of differentiation skills to deal with. Third control points are strictly controlled calcination time and temperature. Fourth control points are the products of the homogenization and analysis. The acid digestion method was used to determine the content of Magnesium Oxide, and the activity of Magnesium Oxide, loss of weight, calcium oxide and shake coefficient were determined.
The quality control points and measures of magnesia cementitious materials products: raw materials containing light burned magnesium chloride, Magnesium Oxide, Magnesium Sulfate, filler and modifier; use of chemical analysis control objectives: the acid leaching method, activity content and content of Magnesium Oxide Magnesium Oxide shake coefficient, calcium oxide content, chloride ion content, alkali metal (potassium sodium) content; the use of physical measures control objectives: water content, fineness, weight, strength, cohesion, stability time.
Batching is divided into two steps: the first step, accounting that ingredients, each kind of material to volume; the second step, the measurement for each material, the fluid with a liquid flowmeter can, on powdery materials, measures are more, electronic belt scale, nuclear scales, scales, scales and balance tipping bucket. Because the vast majority of the production plant selection batch production mode, the idea of selection of tipping bucket scales as a good, small material with the balance.
Product control is divided into three steps: the first step, one by one according to a certain percentage or appearance inspection and proper repair; the second step, according to the rules of the examination in the sampling scale appearance quality; the third step, according to the proportion of extraction in sample appearance and scale inspection of samples of physical and mechanical properties according to the commodity specification the same experiment, including the strength, moisture content, water absorption, halogenation, chloride ion content, impact resistance, frost resistance, screw holding force, surface density, single point hanging force, anti permeability, shrinkage, swelling, dry wet cycle, wind pressure, adhesion, surface density, softening coefficient, fracture load and wear resistance experiment.