一种真空脱气精炼的方法及设备
Technical Field The present invention relates to a vacuum degassing method and apparatus, in particular to one which can be used for refining circulation degassing RH method and apparatus. Background Art To the traditional bof continuous casting processes, refining determines the added value and quality of the final product, this requires many molten steel must undergo RH (RH is vacuum circulation degassing to abbrebyted, is invention of this method the acronym of the Company Rheinstahl-Heraeus) processing. As the market for the quality of the product is greatly improved, in the refining of the need to strictly control the composition of the inclusions in the steel, size, shape, number and distribution. Vacuum degassing device RH is to achieve these objectives the most critical equipment, so as to gradually increase RH processing requirements, converter and gradually become the bottleneck links of continuous casting process. RH device in the, molten steel in a vacuum degassing is carried out in special vacuum chamber of the vacuum. As shown in Figure 1 and Figure 2, is circulating RH refining apparatus for degassing the vacuum chamber 1, the ladle 2, argon gas channel 3, increased by dip pipe 5 and falling impregnated tube 6 composition. This vacuum chamber 1 there are two point sends of refractory material for the molten steel in the molten steel and can be inserted into the dip tube 5 and 6, when the from the argon gas channel 3 impregnation tube to 5 drive gas is filled in, we can encourage ladle 2 through the molten steel in the rise and fall of the impregnated tube 5 and 6 and flows through the vacuum chamber 1 to complete circulation. The this kind of cycle with a relatively small vacuum equipment to batch processing a large amount of molten steel. At present, many steel mills has been successfully application RH circulation degassing device, and gradually become production of high-value-added, high-quality product of the refining device. As for the traditional RH two pipes of the vacuum degassing device, circulating flow rate depends on the geometry of the system, including impregnating pipe diameter and, nozzle position, and the like; and the conditions of operation, comprises a vacuum chamber pressure, argon flow rate, and the like. At present, in order to improve the handling capacity of RH the progressive development of many new technologies. Such as increasing the argon flow rate to increase the circulation flow of the molten steel. However, argon flow rate increase, waste gas of the vacuum chamber, the vacuum degree of damage, the range of requirements is difficult to achieve the degree of vacuum; argon flow rate is too large, the side effects will be a circulation , molten steel ring flow has been reduced. Tohoku University Professor li Baokuan is also proposed to use the multi-tube RH circulation degassing device to improve efficiency and of refining of the molten steel to vacuum degassing device RH the service life is prolonged. Papers published in ISIJ Vol. 40 (ISIJ) (2000), No. 12 (December). As shown in Figure 2, it will rise tube is composed of one to three, and which are uniformly distributed circumferential positions, with a downcomer circulating device to increase the circulation flow of the molten steel flow [...] driving force. By its envisaged water model experimental verification, there is indeed a certain effect, in the field, however, there is a certain difficulty in the operation. One is the existing equipment to a large change, is not easy to be achieved; second, the system is complicated, and inconvenience in operation and maintenance. Content of the invention The invention solves the technical problem that the changes to the existing equipment under the condition of not large, increase the circulating flow of the molten steel, the refining efficiency. The invention is realized according to the following technical scheme: The present invention provides a vacuum degassing process of refining, the impregnated tube is inserted into the bottom of the vacuum chamber in the molten steel, the molten steel in the soaking tube drive-gas, molten steel in a ladle, in through the rising and falling impregnated tube and flows through the vacuum chamber, complete circulation, the invention is characterized in that, in at least one of the periphery of the dip pipe is provided with at least one travelling wave magnetic field generator, the magnetic field generator is capable of generating a consistent with molten steel the electromagnetic force of the circulating direction, the electromagnetic force drives together with the gas circulation flow of the molten steel, the molten steel so as to increase the circulating flow rate. The magnetic field generator can be installed only in the increased by dip pipe, through the produce the upward electromagnetic force to drive the molten steel, can also be installed only in decline in the dip pipe, by generating the downward electromagnetic force to drive the molten steel, can also be installed at the same time in the impregnated tube and rise in the dip pipe, are respectively produce upward and downward electromagnetic force, driving the steel liquid circulation. The present invention provides a vacuum degassing refining apparatus, comprises a vacuum chamber, the vacuum chamber can be inserted into the molten steel in the bottom of the dipping tube and holding the molten steel of the ladle, the ladle is located above the vacuum chamber, one end of the dip pipe is inserted in the ladle, the other end extends into the vacuum chamber; characterized in that at least one of the periphery of the dip pipe is provided with at least one travelling wave magnetic field generator, the magnetic field generator can generate a consistent with molten steel the electromagnetic force of the circulating direction, thereby driving the molten steel flows through the vacuum chamber through the dip pipe complete circulation. The magnetic field generator is a travelling wave magnetic field generator, the iron core and winding can be the use of a planar ferromagnetic material. The iron core is overlapped is made of a silicon steel sheet, into an upper layer and a lower layer, each of the two sides is provided with two D-shaped pipe, form 4 water branch connected in parallel, is used for water cooling. The magnetic field generator winding can be directly water cooling. The magnetic field generator external can is wrapped by a shell body, the shell can be formed by double-layer non-magnetic stainless steel, the middle water cooling. In the cavity in the housing can be filled with pressure slightly greater than atmospheric pressure of dry nitrogen, in order to prevent water vapor from the intrusion, ensure the insulation of the winding. The part of the around the magnetic field generator, such as impregnated tube of the outer cover can be made of non-magnetic stainless steel. The beneficial results of this invention are: 1. The circulation flow RH is increased, so as to increase the processing ability of RH. 2. RH has no influence on the vacuum degree. 3. The electromagnetic force is generated by the device, it does not pollute the molten steel and is not easy to be caused by the splash of molten steel in a vacuum chamber. Description of drawings Figure 1 is a prior art water model RH two tube sections vacuum degassing device. Figure 2 is a prior art multi-tube under vacuum degassing device water model RH cross-sectional Figure. Figure 3 is a prior art vacuum degassing device water model RH a schematic diagram. Fig. 4 is a structure diagram of the magnetic field generator winding and the head. The embodiment of Figure 5 is 1st a schematic diagram of the invention. The embodiment of Figure 6 is 2nd a schematic diagram of the invention. The embodiment of Figure 7 is 3rd a schematic diagram of the invention. Mode of execution As shown in Figure 4, the magnetic field generator is composed of a core 7, a coil winding 8 ;, the generator the outside is made of a shell 9 is wrapped. Iron core 7 and the coil winding 8 can adopt the plane is made of ferromagnetic material. The iron core 7 is made of a silicon steel sheet folded into, is divided into upper and lower two layers, with the two sides of the two D-shaped pipe 10, form 4 water branch connected in parallel, water cooling. Coil winding 8 is made by the flat copper strip, direct water cooling. Housing 9 is composed of a double-layer non-magnetic stainless steel, the middle water cooling. Devices in the inner cavity of the shell is slightly larger than the dry nitrogen atmospheric pressure, prevent water vapor from immersion in order to ensure the copper pipe winding insulation. In Figure 5, 6 and 7 in, the degassing refining equipment RH cycle by the vacuum chamber 1, the ladle 2, argon gas channel 3, travelling wave magnetic field generator 4, increased by dip pipe 5 and falling impregnated tube 6 composition. Increased by dip pipe 5 and falling impregnated pipe 6 are respectively inserted into the two ends of the vacuum chamber 1, the ladle 2, argon gas passage 3 is communicated with the increased by dip pipe 5 ; as shown in Figure 5, the magnetic field generator 4 is increased by dip pipe of the 5 two sides of the above, when the magnetic field generator 4 feed 10-20Hz, 500-800A, 120-200V when the three-phase alternating current, in the ascending impregnated tube 5 travelling wave magnetic field is generated in the molten steel B, a traveling magnetic field to the molten steel in the penetration of the induced current generated therein J, the induced current interacts with the local magnetic field, produce the upward electromagnetic physical F, thus from the argon gas channel 3 input gas (argon) is driven together with the ladle 2 the upward flow of the molten steel in, in a vacuum chamber 1 for circulating treatment, so as to increase the processing ability of RH. In Figure 6 in, the magnetic field generator 4 mounted on the reduced impregnated tube 6 of the peripheral, it can produce the downward electromagnetic force F; Figure 7 in, the magnetic field generator 4 at the same time increased by dip pipe for 5 and falling impregnated tube 6 peripheral, on the rise impregnated tube 5 in the upward electromagnetic force is generated, on the decline impregnated tube 6 in the electromagnetic force generated in the, cycle so as to drive the molten steel flows through the vacuum chamber 1. The present invention provides one kind of vacuum deaeration refining process and equipment. Soaking pipes in the bottom of the vacuum chamber are inserted into molten steel inside the molten steel container, driving gas is introduced into the ascending soaking pipe and the molten steel flows from the molten steel container, through the ascending soaking pipe, the vacuum chamber and the descending soaking pipe before returning to the molten steel container circular. The present invention features that there is magnetic field generator installed outside at least one soaking pipe to produce electromagnetic force in the same direction to that of the circular molten steel and this results in increased circulating molten steel amount and high refining efficiency. 1. A vacuum degassing refining process, the pipe is inserted into the bottom of the vacuum impregnation of the molten steel in the molten steel in the ladle, a dip pipe to which driving is introduced into the gas of the molten steel, the molten steel in the ladle through the dip pipe and flows through vacuum chamber complete circulation, characterized in that it also comprises the following steps: In at least one of the periphery of the dip pipe is provided with at least one travelling wave magnetic field generator, the magnetic field generator is capable of generating a consistent with molten steel the electromagnetic force of the circulating direction, thus circulating the molten steel and gas drives together. 2. Vacuum degassing process of refining according to Claim 1, characterized in that the magnetic field generator can be installed separately or at the same time in the impregnated tube and rise in the dip pipe. 3. A vacuum degassing refining apparatus, comprises a vacuum chamber, impregnated tube and the ladle, the ladle is located above the vacuum chamber, one end of the dip pipe is inserted in the ladle, the other end extends into the vacuum chamber; characterized in that at least one of the periphery of the dip pipe is provided with at least one travelling wave magnetic field generator, the magnetic field generator can generate circulating direction of a consistent with molten steel electromagnetic physical. 4. Vacuum degassing refining equipment according to Claim 3, characterized in that the traveling magnetic field generator adopts a planar winding and the iron core is made of ferromagnetic material. 5. Vacuum degassing refining equipment according to Claim 4, characterized in that the iron core is made of a silicon steel sheet folded into, is divided into upper and lower two layers, with the two sides of the two D-shaped pipe, form 4 water branch connected in parallel. 6. Vacuum degassing refining equipment according to Claim 4, characterized in that the winding can be directly water cooling. 7. Vacuum degassing refining equipment according to Claim 4, characterized in that the magnetic field generator external is wrapped by a shell body. 8. Vacuum degassing refining equipment according to Claim 7, characterized in that the shell consists of a double-layer non-magnetic stainless steel, the middle water cooling. 9. Vacuum degassing refining equipment according to Claim 7, characterized in that the cavity of the shell is filled with pressure slightly greater than atmospheric pressure of dry nitrogen.