A vacuum consumable smelting furnace

Abstract

The invention discloses a vacuum consumable smelting furnace. The vacuum consumable smelting furnace comprises a furnace body with a built-in crucible. A vacuum chamber shell is vertically arranged above the furnace body and is externally connected with a vacuumizing system. Electrodes vertically right facing the crucible are sleeved with the vacuum chamber shell and comprise a transition electrode located on the upper portion and a consumable electrode welded to the lower portion of the transition electrode. The upper portion of the transition electrode is connected to a main lifting shaft. The upper portion of the main lifting shaft penetrates through the vacuum chamber shell through a sliding sealing structure in a sliding mode. The upper ends of the electrodes are fixed to the lower end of the main lifting shaft through an electrode clamping device. The vacuum consumable smelting furnace is characterized in that a butt joint mechanism used for achieving automatic centering of the electrodes is arranged between the upper end of the electrodes and the lower end of the main lifting shaft. The clamping, centering and positioning method is exquisite and stable; operation is easy and convenient; the repeated positioning precision and speed of the electrodes are high; manual operation errors are reduced greatly; the working quality and efficiency are improved.

Description

technical field [0001] The invention relates to the field of vacuum furnace metallurgy industry, in particular to a vacuum consumable smelting furnace. Background technique [0002] Vacuum consumable electrode electric arc furnace, referred to as vacuum consumable smelting furnace, is an electric furnace that uses arc as a heat source to melt metal in a vacuum environment. It is mainly used for smelting refractory metals and rare metals, especially in the field of smelting titanium and titanium alloys. The structure of the vacuum consumable electrode electric arc furnace includes a furnace body with a built-in crucible. A sandwich cooling water chamber is arranged outside the crucible in the furnace body. A vacuum chamber shell is vertically arranged above the furnace body. In this system, the vacuum chamber casing is provided with an electrode vertically facing the crucible. The electrode includes a transition electrode located above and a consumable electrode welded below...

AI Technical Summary

Problems solved by technology

If the main shaft and the electrode are not concentric, there will be a certain angle between the center line of the electrode and the center line of the main shaft due to the action of gravity, and the mating surface will inevitably produce a matching gap. The poor cooperation between the main shaft and the transition electrode will cause a large number of arcing phenomena, which will affect the smelting current. , and it is easy to damage the lower end surface of the main shaft or the corresponding mating surface of the transition electrode, and the loss of the transition electrode is large

The main shaft of the existing vacuum consumable smelting furnace and the transition electrode mainly use a vertical fixture for clamping. The disadvantage of this fixture is that it can only ensure the clamping position of the clamping head and the electrode, and cannot play an automatic centering role in the electrode clamping installation. , so the prior art design can not easily complete the electrode and the main shaft as well as follow-up and crucible to ensure the operational requirements of the center. In actual operation, in order to align the center, the operator often clamps it multiple times, and adjusts the alignment between the electrode and the crucible with multiple ups and downs, and can only judge the actual alignment amount by eyes. This method has low accuracy. , the human error is relatively large, and it is difficult to prevent the radial displacement between the axial direction of the electrode and the center line of the main shaft positioning and the center line of the crucible, which will cause the edge arc phenomenon caused by the poor centering of the electrode in the vacuum smelting to damage the crucible wall. The technical operation is complicated, the electrode repeat positioning accuracy is low, and the operation speed is slow. It is difficult to meet the requirements of batch replacement of electrodes and high-precision repeated rapid positioning during mass production, which greatly reduces production efficiency.

[0005] In addition, when smelting in the existing vacuum consumable smelting furnace, the electrodes are inserted and installed and then energized and heated directly. In this way, if the new electrodes are not treated, the temperature will rise sharply and the phenomenon of bursting or falling off may occur; this affects safety and is more serious. The impact is that after the new electrode billet is blown into the molten pool, the temperature of the molten pool in the crystallizer will suddenly drop due to the excessive temperature difference between the end of the billet and the molten pool, breaking the normal melting environment.

As a result, steel ingots have quality defects such as shells, slag grooves, uneven composition, and impurities, which seriously affect the smelting quality of steel ingots

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