The continuous annealing furnace is generally composed of a heating belt, a soaking zone and a cooling belt, and the steel sheet is heat-treated at 180 ° C in a coil placed in the furnace (see Fig. 1). In the strip continuous hot-dip galvanizing and strip continuous annealing production line, under the action of the reducing atmosphere in the furnace, the iron powder formed and deposited during the cold rolling process of the steel sheet surface is activated, the oxide is reduced to Fe, and the Fe and the furnace roll material are activated. ( mostly heat-resistant stainless steel) It has strong affinity and mutual solubility, and it is easy to spread, adhere and bite on the surface of the furnace roll to form a build-up. When the steel sheet is conveyed through the roll surface, a pit is left on the steel sheet to affect the surface quality of the steel strip. With the rapid development of the automotive industry, higher requirements are placed on the surface quality of cold-rolled and galvanized steel sheets. In order to improve the quality of steel sheets, people have developed CAPL and CGL furnace roll coating technology--using thermal spraying methods in the furnace. The surface of the roll is sprayed with a layer of low affinity with iron, a coefficient of thermal expansion matching the base material of the furnace roll, high temperature wear resistance, and a coating capable of maintaining surface roughness for a long period of time. The coating can reduce the generation of the surface area of ​​the roll of the roll, and thus can obtain a high quality automotive steel plate having a good surface quality. Furnace roll coating technology began in Japan in the 1980s and was widely applied to almost all CAPL and CGL furnace rolls in the mid-1980s. It was valued and applied in Europe and the United States in the late 1980s. In 2001, Baosteel Machinery Factory conducted research on the mechanism of furnace roll accumulation in China. The coated hearth rolls produced by supersonic flame spraying and plasma spraying process were successfully applied in the continuous annealing furnace of Baosteel Cold Rolling Mill. At present, according to the different use temperatures of the furnace rolls, a series of coating materials have been researched and developed at home and abroad to adapt to the different conditions of use of the furnace rolls. The coating materials containing boride and nitride developed by Japan, the United States and other countries have excellent anti-tumor performance, and the longest life of the roller can reach more than 3 years. In the past few years, Baosteel Machinery Factory has developed galvanized steel sheets and cold-rolled strip steel anti-counterfeit coating furnace rolls, which have a longest life of more than 3 years. In order to develop the anti-counterfeit coating of the furnace roll faster and more effectively, the furnace roll accumulating simulation test machine with different characteristics has been developed in foreign countries. When the steel plate and the furnace roll are slightly slipped, the residue on the surface of the furnace roll grows on the surface of the furnace roll to form a buildup, which seriously affects the quality of the steel plate. Therefore, the build-up test machine mostly simulates the sliding process on the continuous annealing line. The relevant testing machines currently produced and used abroad mainly include the following: (1) The stacking tester evaluates the surface cleaning effect of the deposited part under high temperature and air atmosphere, and is applied to the development of the self-cleaning coating of the bottom roller of the high temperature annealing line. (2) Nippon Steel Tester evaluates the anti-tumor property of coatings at 800 °C, nitrogen-hydrogen (5 % H2) atmosphere and under different pressures. (3) The two-roller simulator evaluates the stacking resistance of the coating by simulating the stacking caused by the sliding speed difference between the two rolls by simulating the difference in the speed of the two rolls. In summary, the continuous annealing furnace roll is the core component of the continuous annealing production line of the metallurgical industry. The quality of the furnace roller directly affects the quality of the steel strip, and the life of the furnace roller directly affects the efficiency of the production line. In order to improve the anti-tumor performance of the surface of the furnace roll, it is very effective to make the furnace roll to be thermally sprayed. In order to develop the anti-counterfeit coating of the furnace roller faster and more effectively, based on the advantages and disadvantages of the foreign testing machine, I developed a dynamic simulation test device for the furnace roll, which realized the dynamic simulation of the production line furnace in the laboratory. Rolling conditions, which greatly shortens the development time and cost of anti-biofilm coating. First, the working principle of the testing machine When the dynamic test machine of the furnace roll build-up characteristic is working, the electric furnace is heated according to the actual working condition parameters of the furnace roll, and the same proportion of working atmosphere is introduced into the electric furnace according to the requirements. The powder is sprinkled between the samples in the simulated working condition (such as Fe3O4, MnO, ferromanganese, etc.), the sample plate and the semi-circular roll surface are pressed, the motor drives the semi-circular roll to oscillate, and the sliding between the sample plate and the semi-circular roll, between the sample plate and the sample plate, simulates the actual production of the steel strip and the furnace Sliding between the rollers. The motor-driven sample plate generates relative motion in a high-temperature specific atmosphere as required, and closely simulates the actual working environment and working condition of the high-temperature furnace roller. During the work, the test machine control system monitors and controls the parameters of furnace temperature, atmospheric pressure, oxygen content in the atmosphere, loading pressure, and sliding speed of the sample, and records them in real time. The built-in tumor testing machine is matched with the control cabinet and the real-time monitoring computer, which can realize the automatic control of the whole process of the experiment. Second, the test machine composition The testing machine consists of sample parts, heating temperature control parts, sample pressing parts, sample driving parts, cooling and heat insulating parts, air supply parts, atmosphere control parts, and sealed exhaust explosion-proof parts (see Figure 2). Next page 36 Inch Ceiling Fan,36 Inch Outdoor Ceiling Fan,36 Inch Indoor Ceiling Fan,Ceiling Fans 36 Inch With Light Jiangmen MagicPower Electrical Appliances Co.,Ltd. , http://www.magicpowerfans.com
