Application of hard surfacing technology in various fields
hard surfacing is the process of surface hardening of wear-resistant parts. High hardness flux cored wire and wd-bx1 professional open arc flat welding equipment are used for surface surfacing, so that the surface of wear-resistant parts forms high chromium composite carbides that are more wear-resistant than the base metal, and the high chromium carbides can be well combined with the base metal. Using this technology will save more than 50% of the purchase cost, and the effective production and use time is more than twice that of the original new product. For example, when an enterprise purchases new products for production activities, when the wear-resistant parts are worn below the optimal production efficiency (the wear amount accounts for a small part of the total weight of the new products), the enterprise will scrap the parts and re purchase them. Then most of the rest of the scrap treatment is uneconomical, increasing the purchase cost and increasing the economic burden of the enterprise. Because hard surfacing technology can reduce the purchase cost and prolong the service life of wear-resistant parts, it has been widely concerned and applied in various industries. The following introduces the application of hardfacing technology based on the actual situation of various industries
1. Application of hardfacing surfacing technology in iron and steel industry
the working environment of wear-resistant parts in iron and steel plants is very poor. During the production process, the temperature is high and the cold and heat cycles are frequent, which accelerates the wear of wear-resistant equipment and increases the maintenance cost of the steel plant and the labor intensity of the staff. For example, the continuous casting roll in the steel plant is the main body of the continuous rolling mill. In the production process, the continuous casting roll forms the billet by generating extrusion force. This working principle causes the continuous casting roll to be affected by the high temperature of the billet and the reaction force, which will produce non fatigue cracks on the surface of the continuous casting roll, which can be seen visually, or even fall off in pieces. It brings great inconvenience to production and operation, affects production efficiency, and even causes shutdown. Many steel mills are well aware of the fact that the mobile beam can be driven to realize loading, the delivery period for purchasing new products is long, and the production cost has also increased by more than half. Taking a continuous casting roll in a continuous rolling mill as an example, when the roll is worn below the optimal productivity, the actual consumption is less than 1/10 of the overall roll, so the scrap treatment of 9/10 of the cast roll is uneconomical. Therefore, most iron and steel plants adopt hard surfacing technology, surfacing hard alloy on the surface of the discarded roller until it is stacked to the original surface size of the roller. In this way, 2. The quality of electromechanical and oil pump directly determines the service life and noise of the universal experimental machine, reducing the production cost by more than half; 2. Shortening the time to resume production; in addition, the steel throughput increases by 8-10 times, which is economical and reasonable
2. Application of hardfacing surfacing technology in cement production enterprises
at present, new dry process production lines are booming in China, and vertical mills are widely used in cement production lines because of their low energy consumption. For example: raw meal grinding, clinker grinding, pulverized coal grinding and slag grinding. Therefore, vertical mills (usually called vertical mills) have become the focus of attention of relevant enterprises, which also came into being many service projects. One of them is the hard surfacing engineering service of the grinding roll sleeve and grinding disc liner of the vertical mill
improving the wear resistance of grinding roll sleeve and grinding disc lining has become a hard index for cement manufacturers applying vertical mills. Because the vertical mill is one of the important production equipment of cement production enterprises. However, the wear of the grinding roll sleeve and the grinding disc lining is subjective. To a certain extent, the wear-resistant parts have increased the clearance of the parts due to the lack and deformation of the surface, so they cannot be well ground, so as to reduce the production efficiency, improve the production energy consumption, and even cannot be produced
according to the considerable profits in the current cement market, a day's shutdown will cause at least hundreds of thousands of net profit losses to large cement production enterprises. It is imperative to improve production efficiency or resume production as soon as possible. Because the maintenance method of replacing new products requires a lot of procurement costs, and the supply cycle is relatively long, if it is used in the unplanned maintenance of cement production enterprises, it will be far from enough. Therefore, "emergency service hard surfacing" is the ideal choice for the majority of cement owners using vertical mills
the hardfacing surfacing of wear-resistant parts in cement production enterprises can be diversified in service forms, that is, they can be disassembled and transported to the surfacing repair factory for surfacing repair, or repair welding in the mill without disassembling the mill. Take the raw mill of cement production enterprises as an example: as the domestic cement production line tends to be large tonnage, the overall size of the vertical mill will be correspondingly increased to meet the production volume. Most of the outer diameter of the grinding disc is not less than 3 meters. Due to the large space in the mill, wd-bx1 portable welding equipment can be easily erected into the mill or multiple sets. Carry out hard surfacing of grinding roll sleeve and grinding disc lining. Thus, a lot of disassembly costs are saved, the labor intensity of workers is reduced, and the maintenance period is shortened. Especially in the case of cement production enterprises without spare parts, this technology of surfacing in the mill is the favorite of cement owners. Compared with new spare parts, the cost is low, the construction period is short, and the wear-resistant life can be increased by more than 2 times. It is the economic first choice of cement production enterprises
domestic or imported vertical mills are widely used in China. The base materials of the roller sleeve and lining bush of the vertical mill are generally the following: high chromium cast iron, nickel chromium alloy, etc. these materials are suitable for surface surfacing, but professional welding equipment and special welding materials must be selected. The wear causes of wear-resistant parts of vertical mill are analyzed, including the impact on the equipment when raw materials are fed, the shear force generated between the contact edge of grinding roll and grinding disc and the material, plus the reaction force received by the mill when grinding the material, so that the surface grooves and ridges of wear-resistant parts are alternately changed, so that the surface size of wear-resistant parts is reduced, the gap is increased, and the production efficiency is affected. The surfacing technology of Shenyang Weide welding can be used to surfacing split parts, plane parts and conical parts. For example, the conical grinding roller is seriously worn, and when the big end has been ground flat, the professional technology of Shenyang Weide welding is used to carry out the transition wear-resistant layer, so as to prevent the base metal from being closely combined with the wear-resistant layer, which will cause the wear-resistant layer to fall off during operation
surfacing in the mill is economical, easy and reasonable, and has been widely used
3. Application of hardfacing surfacing technology in power plants
thermal power generation is the leader in the domestic power industry, and it is also the result of the wide distribution of coal resources in China. Most thermal power plants burn pulverized coal and use vertical mills to grind pulverized coal. Due to the influence of coal quality, the impact of opposed mill is also quite serious. When the coal mill is running, it mainly grinds and squeezes the coal block and the dry coal stone containing a large amount of impurities. After long-term operation, the surface of the grinding roll will appear groove scale wear, and the surface of the grinding disc will appear an annular groove with a width of about 7~11 cm on the contact surface with the grinding roll, making the working efficiency of the coal mill lower and lower, and increasing energy consumption
at this time, the hard surfacing technology is used to overlay the surface of the grinding roll and the grinding disc, so that the wear-resistant layer is formed on the surface of the wear-resistant parts, and various performance indicators are better than new castings. The digital display electronic tensile testing machine can detect the stretching, tearing, peeling, tightening, bending, shearing, bursting, puncturing, fatigue and other items of metal materials, non-metallic and high molecular materials, which is also determined by the casting process itself
in fact, hardfacing surfacing technology is widely used in many fields, such as mining, food, casting, etc... due to the precious space of your magazine, the industries listed above are very limited, and you have the opportunity to communicate again
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