Confucius decoration study decoration cement decoration home decoration decoration company decoration find decoration company okay tile price Roll Up Door Servo Motor,Automatic Roller Shutter Door Opener,Roller Shutter Door Servo System,Glass Sliding Door Motor Shenzhen Hongfa Automatic Door Co., Ltd. , https://www.highspeedshutterdoor.com
(1) Specific gravity and bulk density: The specific gravity of common cement is 3:1, and the bulk density is usually 1300 kg/m3. (2) Fineness: It refers to the thickness of cement particles. The finer the particles, the faster the hardening and the higher the early strength.
(3) Condensation time: The time required for cement to add water to start coagulation is referred to as the initial setting time. The time required to complete the stirring from the addition of water is called the final setting time. The initial setting time of Portland cement is not earlier than 45 minutes and the final setting time is not later than 12 hours.
(4) Strength: Cement strength should meet national standards.
(5) Volume stability: refers to the uniform performance of cement volume change in the hardening process. The cement contains many impurities and will produce uneven deformation.
(6) Heat of hydration: The effect of cement and water will produce an exothermic reaction. In the process of cement hardening, the constant release of heat is called heat of hydration.
â– Commonly used cement varieties:
(1) Portland cement: Portland cement clinker containing calcium silicate as the main component is added by adding a proper amount of gypsum.
(2) Ordinary portland cement: It is made of Portland cement clinker, added with appropriate amount of gypsum and mixed materials.
(3) Slag Portland cement: It is made from Portland cement clinker, mixed with appropriate amount of granulated blast furnace slag and gypsum.
(4) Pozzolanic Portland cement: It is made by mixing and grinding fine Portland cement clinker and pozzolanic material and gypsum.
(5) Fly ash portland cement: Made of Portland cement clinker and fly ash, mixed with appropriate amount of gypsum and ground.
Commonly used cement labels: No.225, No.275, No.325, No.425, No.525, No.625 and so on. Their tensile strength is different because of different varieties, and their labels are different. The MPa value is between 2.8-4.5 and 3.4-8.0.
â– Decorative cement varieties Decorative cement is commonly used to decorate the surface of buildings. It is simple in construction, convenient in shape, easy to maintain, and inexpensive. There are several varieties as follows: (1) White Portland cement: Calcium silicate as the main component, plus a small amount of iron clinker and the appropriate amount of gypsum ground.
(2) Color Portland cement: White Portland cement clinker and high-quality white gypsum, mixed with pigments and admixtures, are ground together. Common color additive pigments are iron oxide (red, yellow, brown, black), manganese dioxide (brown, black), chromium oxide (green), cobalt blue (blue), ultramarine blue (indigo), peacock blue (sea blue) ), carbon black (black) and so on.
Decorative cement is similar to Portland cement in that it has the same construction and maintenance, but it is relatively easy to pollute and the instruments and tools must be clean.
â– Usage and purchase of cement mortar In home decoration, cement mortar is used for floor tiles, wall tiles, and masonry. It not only enhances the adsorption capacity of the surface material and the substrate, but also protects the internal structure. As a leveling layer for building rough surfaces, cement mortar is an indispensable material in the renovation project.
Many customers believe that the greater the proportion of cement in the entire mortar, the stronger the adhesiveness, and therefore often disagree with the decoration company on the use of cement. In actual fact, in the case of paste tiles, if the cement number is too large, when the cement mortar condenses, the cement absorbs a large amount of water. At this time, the ceramic tile surface moisture is easily absorbed and cracked, shortening the service life. Cement mortar should generally be stirred at a ratio of cement:sand=1:2 (volume ratio).
At present, there are many varieties of cement on the market, such as Portland cement, ordinary portland cement, and slag portland cement, etc. Silicate cement is commonly used for home decoration.
â– The principle of buying cement and sand In order to ensure the quality of cement mortar, cement must be paid attention to whether or not to produce 425# portland cement. Sand should be selected sand, the sand thickness of the particles is very suitable for use in cement mortar. Many customers think that the better the sand, the better the mortar is, in fact, a misunderstanding. Too fine sand adsorption capacity is not strong, can not produce a large friction and stick to the tile.
Cement knowledge Raiders
The main technical performance indicators of cement: