Address: Bian Dong village, Gaosheng Town, Panshan County, Panjin City, Liaoning province.
Contact: regular Manager
Factory location: 0427-7501678
The composition of petroleum coke carbon additives is generally C:96-99%, S0.3-0.7%. It is mainly used for steelmaking, gray iron, brake pads, cored wire and so on.
Petroleum coke carburizer, mainly produced in Liaoning, Tianjin and Shandong, Liaoning mainly produces projectile coke, used for casting is not good, Shandong and Tianjin petroleum coke can be used for casting gray iron. The composition is generally C:96-99%; S0.3-0.7%. It is mainly used for steelmaking, gray iron, brake pads, cored wire and so on. 1. selection of burden
(1) scrap steel used for producing nodular cast iron in scrap steel should be carbon scrap. It should not contain elements that impede graphitization, such as chromium. It should not contain anti nodular alloy elements. The lump of scrap steel should be about 30% thick, and it can be placed flat in the furnace.
(2) carburizing agent: high quality coke. The sulphur content is low, the lump is 60 ~ 80mm, and has high intensity. 2. Scrap electrode blocks. It is best to have a certain length to facilitate cutting into molten iron.
(3) pig iron is mainly used to adjust carbon content in molten iron. We hope to use high carbon low sulphur pig iron with wC > 4%. The silicon content in pig iron is higher than that in the pig iron, and the production of ductile iron can be reduced by adding ferrosilicon.
(4) spheroidizing agent and inoculant are used according to the traditional technology and conform to the actual situation of each factory.
Melting process: coke block + scrap steel electrode block heating picking out coke block and electrode block sampling analysis pig iron furnace charge sampling analysis Si, Mn heating ferromanganese ferrosilicon furnace inoculation spheroidizing pouring.
The matters needing attention in the smelting process are as follows:
(1) coke blocks are placed on the bottom of the furnace, with the aim of creating longer soaking time for coke blocks in molten iron. The amount of coke block is about 5% of scrap steel. Scrap steel is melted about 50%, and thick sheet scrap steel is used to cover it. The coke can also be replaced by 60-80 mm waste electrode block in the furnace bottom as a charring agent. The sulfur content is lower, which is more favorable to obtain high quality ductile iron.
(2) the utilization ratio of scrap steel is mainly determined by the efficiency of increasing carbon. Start using this method to produce nodular cast iron manufacturers, around 30%. After increasing the efficiency of carbon increasing, the proportion of scrap steel is gradually increased. Excessive use of scrap steel will affect the carbon and silicon equivalent of the final product if the efficiency of carbon addition is not high.
(3) scrap steel is melted and cut into electrode rods, and the furnace temperature is increased appropriately, and the efficiency of increasing carbon is increased. However, too high furnace temperature and increased power consumption are also harmful to lining.
(4) if the carbon content is high enough, coke and electrode rods should be removed to analyze the carbon content.
(5) according to the analysis results, the dosage of pig iron and the amount of recycled ductile iron are calculated.
(6) according to the estimation of silicon content, decide whether the total amount of molten iron can be filled with the recycled material.
(7) after melting, the samples were analyzed for the contents of Si and Mn alloy elements.
(8) Increase the temperature of molten iron properly, supplement the alloy elements according to the analysis results, and add ferrosilicon before discharging after reaching the discharging temperature.
(9) ferrosilicon is melted into molten state and discharged immediately.
(10) spheroidization, inoculation and pouring are carried out routinely.
3. component adjustment calculation
It is well known that the mechanical properties of ductile iron mainly depend on chemical composition, cooling rate (as-cast ductile iron) and heat treatment process. Chemical composition is internal, fundamental and variable. Almost every stove is different. Therefore, we must strengthen the testing of chemical components and seriously adjust them, so we should not adopt "fixed proportion production". Carbon equivalent is especially important in chemical composition. Especially, the nodular cast iron produced with scrap steel as the main burden is difficult to control the carbon increase efficiency and the carbon equivalent fluctuates greatly, so the carbon equivalent should be adjusted.
(1) calculate the amount of pig iron and calculate the amount of pig iron based on the analysis of carbon content. In fact, it is necessary to adjust the carbon equivalent of ductile iron so that the carbon equivalent of molten iron formed by pig iron and scrap steel can reach the carbon equivalent required by ductile iron.
Pig iron addition = scrap steel addition * carbon content required for ductile iron - Analysis of carbon content) / (carbon content required for pig iron - carbon content required for ductile iron)
(2) It is basically normal to calculate the carbon equivalence of the returned ductile iron by the addition amount of the returned ductile iron, and the addition amount is not large. Therefore, after adding the iron into the furnace, the carbon content of the molten iron in the furnace is qualified.
The amount of returned ductile iron = total charge - Scrap addition - pig iron addition.
(3) the formula for estimating silicon content is as follows:
Silicon Content (Scrap+Pig Iron+Ductile Iron Addition) X Silicon Content/Furnace Charge 100% Allowable Silicon Content of Raw Iron
When the estimated silicon content is too high, the amount of returned ductile iron is reduced to 9:1 pig iron and scrap steel.
(4) the calculation formula for the addition of ferrosilicon is as follows:
Ferrosilicon Content = [Furnace burden total * (Ductile iron requires silicon content - inoculation silicon content - spheroidization silicon content - Analysis silicon content)]/ Ferrosilicon content
(5) the calculation formula for manganese and other alloying elements is as follows:
The effect of silicon carbide on the content of alloy elements in alloy iron
Silicon carbide has a wide range of applications, such as metallurgy, machinery, chemical industry, building materials, light industry, electronics, heaters. Abrasives can be used as purifying agents, deoxidizing agents and improver in metallurgical industry. It can be used as a synthetic cemented carbide tool in mechanical processing, and the processed silicon-carbon plate can be used as a refractory for ceramic firing shed plate. The fine powder produced after finishing can be used for coating of high-tech electronic components and far-infrared radiation materials. High purity fine powder can be used for coating the aerospace industry vessels of defense industry. It is widely used in international and domestic economic fields.
1. Abrasives--Because silicon carbide has high hardness, chemical stability and certain toughness, silicon carbide can be used to make consolidated abrasives, coated abrasives and free grinding, thus processing glass, ceramics, stone, cast iron and some non-ferrous metals, cemented carbides, titanium alloys, high-speed steel tools and grinding wheels.
2. Refractory and Corrosion Resistant Materials--Silicon carbide can be used in abrasives, ceramics kilns, shafts and saggers, vertical cylinder distillation furnaces for zinc smelting industry, silicon carbide bricks, aluminium electrolyzer lining, crucibles, small pieces of furnace materials and so on, mainly because of its high melting point (decomposition temperature), chemical inertia and thermal shock resistance. Silicon carbide ceramic products.
3. Chemical uses - because silicon carbide can be dissolved in molten steel and reacted with free oxygen and metal oxides to form carbon monoxide and silicon-containing slag. Therefore, it can be used as purifying agent for steelmaking, which is used as steelmaking deoxidizer and cast iron structure improver. This generally uses low purity silicon carbide to reduce costs. At the same time, it can also be used as raw material for making four silicon chloride.
4, electrical purposes - used as heating elements, nonlinear resistance elements and high temperature semiconductor materials. Heating elements such as silicon carbon rod (suitable for 1100 ~ 1500, all kinds of electric furnaces), non-linear resistance elements, various lightning arresters.