Copper pipe horizontal continuous casting gas shield crystallizer and method for preparing copper alloy pipe through copper pipe horizontal continuous casting gas shield crystallizer

Abstract

The invention discloses a copper pipe horizontal continuous casting gas shield crystallizer and a method for preparing a copper alloy pipe through the copper pipe horizontal continuous casting gas shield crystallizer. A liquid inlet is formed in the lower portion of a graphite jacket of the crystallizer, and a pressing plate, a flange and a cooling copper sleeve are sequentially arranged in the middle of the graphite jacket in a sleeved mode from bottom to top. A cooling water jacket is arranged on the inner side of the pressing plate, an electromagnetic generating cavity is formed in the cooling water jacket, and a plurality of electromagnetic coils are arranged in the electromagnetic generating cavity. A cooling coiler is arranged in an inner cavity of the cooling copper sleeve, one end of the cooling coiler penetrates through a cooling copper sleeve jacket and is connected with an air inlet and an inert gas source, and the other end of the cooling coiler sequentially penetrates through a cooling copper sleeve inner sleeve and the graphite jacket and is connected with an air outlet. According to the crystallizer adopted for horizontal continuous casting, through the electromagnetic stirring effect, liquid metal can flow and transfer heat and media in an inner cavity of the crystallizer so that the effects of refining grains, enabling a solidification structure to be finer and improving casting quality can be achieved; meanwhile, through a gas shield system, attachments on the inner surface of the graphite jacket are reduced obviously and are dispersed relatively, and the service life of the graphite jacket can be prolonged by 50% compared with that of original graphite jackets.

Description

technical field [0001] The invention relates to the field of copper alloy pipe production equipment and technology, in particular to a gas-protected crystallizer for horizontal continuous casting of copper pipes and a method for preparing copper alloy pipes. Background technique [0002] Copper tubes and copper alloy tubes are key materials for seawater desalination, thermal power nuclear power and heat exchange systems in ships. At present, the main method of producing copper alloy pipes is the extrusion method. Other methods such as oblique casting and perforation are used, and continuous casting and rolling are rarely used. Extrusion, pickling, and then rolling and stretching to finished pipes have the following disadvantages: (1) The production process is complicated, there are many auxiliary facilities, the maintenance cost of the mold is high, the floor area is large, the personnel requirements are high, and the quality requirements are high; (2) The investment scale ...

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Problems solved by technology

At present, the main method of producing copper alloy pipes is the extrusion method. Other methods such as oblique casting and perforation are used, and continuous casting and rolling are rarely used. Extrusion, pickling, and then rolling and stretching to finished pipes have the following disadvantages: (1) The production process is complicated, there are many auxiliary facilities, the maintenance cost of the mold is high, the floor area is large, the personnel requirements are high, and the quality requirements are high; (2) The investment scale is large, ranging from hundreds of millions of yuan to hundreds of millions of yuan; (3) The secondary heating of the round billet requires extrusion molding, extruding cylinders, needles, and high energy consumption such as preheating before work; ( 4) Stirring, ingot casting, sawing, heating, pressing, peeling, pickling and other processes have large metal losses, low yield, and the yield of billets is less than 90%; (5) Semi-continuous casting or split furnace is used Furnace melting and casting, poor production continuity and low efficiency; (6) large zinc burning loss, stirring, reheating, extrusion and lubrication, etc., smoke and serious pollution; (7) large eccentricity of the tube billet affects subsequent cold processing, especially the forward Extruded large-diameter thin-walled brass tubes have an extruded yield of 40% to 60%

In the condenser tube market, HSn70-1 and Ha177-2 brass tubes, BFe10-1-1 and Bfe30-1-1 white copper tubes are widely used, among which HSn70-1 and Ha177-2 brass tubes are used if horizontal continuous casting , with the solidification and shrinkage of the metal, the liquid metal on the graphite mold shrinks from only the graphite wall to a certain gap. The alloy composition in the brass also contains more zinc, and the melting point of zinc is low. Part of the zinc in the area will volatilize and condense on the graphite mold of the crystallizer, and the outside air will easily penetrate into the gap from the outlet end of the tube blank, and react with the semi-solidified metal zinc on the graphite mold, thereby forming oxides that adhere to the graphite mold. On the wall, the friction force of pulling out the tube blank is increased, and the heat transfer effect is affected, which greatly shortens the service life of the graphite template; and as the production progresses, more and more oxides are adhered, and the When contacting with solidified metal, it is easy to cause cracks in the tube blank. If the oxide falls off and is embedded in the inside or surface of the tube blank, the ductility of the matrix will be destroyed.

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