Having thus described the origin and uses of the pigment, we now come to the question, what is lithopone? It is, in short, a chemical compound usually consisting of 30.5 per cent zinc sulphide, 1.5 per cent zinc oxide and 68 per cent barium sulphate, but these proportions vary slightly in the different makes. Lithopone of this composition is sold as the highest grade, either as red seal or green seal, as it best suits the idea of the manufacturer. Many manufacturers, especially in Europe, sell and also export other brands under other seals, containing 24, 20, 18 and as little as 12 per cent of zinc sulphide with very small percentages of zinc oxide, the balance being usually barium sulphate, but sometimes certain portions of China clay or gypsum (calcium sulphate) or whiting (calcium carbonate). Such brands are not a chemical compound, but mechanical mixtures of the chemically compounded lithopone and the admixtures referred to.
In 2022, a year after the EFSA recommended against the use of E171, the Food Standards Australia New Zealand (FSANZ) conducted its own reassessment of titanium dioxide as a food additive. The agency concluded that titanium dioxide was indeed safe to use as a food additive. The United Kingdom and Canada came to similar conclusions.
Others are looking into recycling waste streams from the manufacturing process to recover titanium compounds, thus closing the loop on material use Others are looking into recycling waste streams from the manufacturing process to recover titanium compounds, thus closing the loop on material usetitanium dioxid manufacturer.The steel mesh is also called longitudinal reinforcement and transverse reinforcement. The longitudinal reinforcement and transverse reinforcement are spaced at right angles to each other, and all the crossing points are welded together. It has the characteristics of crack – proof, small error and good quality. Steel mesh is mainly used in coal mine roadway, concrete pavement, bridge deck, airport runway and buildings. So, what are the advantages of mesh?
The use of electric welding mesh is very wide, can be used in many places. In the field of construction, especially the wall crack, has played a very important role, the traditional construction, is to put on mortar directly onto the wall, after such a long time, will appear fall off and fracture phenomenon, in order to prevent the occurrence of this phenomenon, must use welded wire mesh before rendering, welded wire mesh is fixed to the wall, above the plastering construction, Can ensure that the wall level for a long time, not easy to crack phenomenon.
The entire steel surface is protected, and the melted zinc is easily coated evenly, whether in the interior of the pipe fitting in a depression, or in any other corner where the coating is difficult to access. The hardness of galvanized coating is greater than that of steel. The Eta layer of the upper layer of Z is only 70 DPN hardness, so it is easy to be dented by collisions. However, the hardness values of the lower layer of Zeta layer and delta layer are 179 and 211 DPN respectively, which are higher than that of the iron material of 159 DPN. Therefore, its impact resistance and wear resistance are quite good.
Now large roll galvanized wire in our life the use of more and more, to galvanized wire products bring a great market, galvanized wire products are more and more types. The surface coating of good quality galvanized wire is continuous and smooth. When the plating parts are installed and combined, there can be no flow hanging, slag or drop remaining, and no surface defects such as iron exposure. Good quality galvanized wire, coating must be uniform, roughly uniform in copper sulfate solution soaking five times without exposing iron. And with hammering test does not bulge, do not fall off. This is a good galvanized wire should have characteristics.
Generally, due to wet weather and more precipitation, oxidation and rust of binding iron wire NetEase occurs, so we should better store and use galvanized iron wire to avoid rust as far as possible. About the barbed wire, the surface of the barbed wire attached a layer of galvanized layer, the galvanized layer if too thick will not meet the SGS environmental standards. But if it is too thin, it is easy to oxidize with water molecules and rust.
Many people do not know how to choose high quality cut wire, I will give you a detailed introduction. The raw material of cutting wire is divided into: stainless steel cutting wire, copper cutting wire, steel wire cutting wire, copper plated steel wire cutting wire, galvanized steel wire cutting wire, iron wire cutting wire, aluminum wire cutting wire and so on.
The quality of hot-dip galvanized barbed wire is only the zinc layer attached to the surface of the wire, and with the chemical reaction, the zinc layer on the surface will gradually lose its role because of the oxidation reaction, which is more prominent in the humid environment. And because the use of rusty wire after all, it is said that the quality of hot-dip galvanized barbed wire is certainly not up to the level of stainless steel barbed wire.
Galvanized hook mesh selection of low carbon steel wire, the surface of cold galvanized or hot galvanized anticorrosive treatment, strong mesh, strong protection, long anticorrosive time. Galvanized wire hook nets are widely used, widely used in warehouses, refrigeration between things, protective reinforcement, parks, zoos, Marine fishing fences and construction site fences, mechanical equipment protection.
In order to remove the photosynovium and oxide remaining on the surface of galvanized iron wire after drawing or heat treatment, it is necessary to do the surface treatment of galvanized steel wire before plating. The common surface of low carbon steel wire is the light synovium or oxide of animal or vegetable oil; Medium and high carbon steel in addition to contain animal or vegetable oil components.
Cooling can be in the groove close row of thin wall plastic pipe, through the flow of tap water for cooling, can also be used as a temperature control device titanium pipe. In the process of electroplating galvanized wire, it is necessary to stir the plating solution to obtain the composite coating with particles dispersing in the matrix metal. Stirring methods include mechanical stirring, air stirring, ultrasonic stirring, bath circulation, etc.
During this process, each time the wire is pulled over, the surface hardens due to the high friction temperature. So basically every time you pull it you have to annealing it in the furnace. On the one hand, it is to reduce the surface hardness. On the other hand, during the process of wire pulling, only the surface is deformed, and the center is unchanged. So there’s a lot of stress inside. Therefore, it is necessary to rely on annealing to eliminate the internal stress, so that the wire becomes soft again to eliminate the stress before being drawn again.
In order to make the zinc content of steel wire stable in the future, and maintain its uniformity, as far as possible to reduce the zinc content, and effectively reduce zinc consumption to the actual work, the following measures are proposed by the wire factory:
High quality galvanized wire in general, the zinc layer attached to the surface of the wire is relatively thick, so when we buy galvanized wire, as long as we look at the thickness of the zinc layer machine, we can generally judge whether the quality of galvanized wire is high quality.
