What are the common problems in vacuum induction furnace smelting
Vacuum induction furnace is an important equipment for vacuum smelting. At present, it is mainly used for smelting precision alloys, alloy steel, electromagnetic materials and high temperature materials. Has two kinds: vacuum induction furnace is intermittent and semicontinuous respectively, the furnace capacity is less than 150 kg of commonly used intermittent, between 150 and 300 kg capacity of both can be used, and capacity in more than 500 kg is using semicontinuous.
1. Spray problem of vacuum induction furnace smelting:
In vacuum induction furnace smelting when this problem is mainly caused by these two reasons: one is the melting speed, the inside of the furnace charge gas is not fully discharge, or is the bridge of the problems in the process of melting, a liquid metal temperature at the bottom of the crucible, large cold suddenly fall into the molten pool inside, this will cause spillage; Another reason is that the addition of alloy material, and the gas content is higher, join too fast, high temperature, it fully deflated to melt into a liquid, so also easy to cause spillage. So how to solve the problem of vacuum induction furnace smelting?
Solution: a way from raw material to prepare and begin charging, the choice of the appropriate power supply system, when melting operation carefully, avoid the happening of bridge condition, and at the time of adding alloy materials, the fuse first ChiGang liquid to the right temperature, and then slowly to join, avoid the happening of the splash. The other way is to cool down properly after the splash, slow down the reaction, and let the boiling slow down. When a large splash occurs, argon can be pumped into the furnace, reducing the vacuum, increasing the pressure inside the furnace, and then continuing to pump out after the boiling steel has calmed down.
2. Problems of slag rings in vacuum induction furnace smelting:
There are two reasons for this problem in the process of smelting: the molten steel of the crucible is splattered continuously during the long smelting process, thus forming a slag ring. Another reason is the high gas content in the steel liquid, which rapidly formed the slag ring when it was pumped out.
Solution: there are three solutions. First, after the formation of the slag ring, the slag ring can be ironed out by increasing the loading amount and tilting back and forth when washing the furnace. Second, for the slag rings that have already left the arc, they can be treated by feeding basket. Third, for large slag rings, the welding with the crucible has been relatively firm, so the vacuum can be broken by direct welding or welding.
3. Bridge problem in vacuum induction furnace smelting:
The bridge problem in smelting is mainly caused by the following reasons: the furnace material is too long; When carbon monoxide steel is added, carbon monoxide plate is added at later stage and welded at melting time. The slag ring is too large to bridge.
Solution: there are three solutions: first, use the hammer to break open; Second, tilt the crucible, using molten steel water to iron the bridge site; Third, for serious bridging, a broken vacuum can be adopted.