(1) The type of crucible furnace is classified as follows according to the mode of operation.
1) The combustion support system in the structure of the stationary crucible furnace for burning heavy oil in the stationary crucible furnace includes primary air and secondary air, and the secondary air enters the burner brick through the air conditioner.
2) Tilting crucible furnace Tilting crucible furnace is roughly divided into two categories: center tilting and front tilting according to the position of its tilting fulcrum.
In addition to the manpower used for the center tilting fulcrum, electric motors, hydraulic pressures, water pressure, etc. are used. For example, it is called the front fulcrum hydraulic tilting type, the center fulcrum electric tilting type, etc.
The tilting state of the front fulcrum hydraulic tilting crucible furnace indicates that the crucible furnace is the best in terms of furnace operation, because it ensures that the ratio of molten copper to the furnace is always constant. The position of the central fulcrum type is too varied, and the operating conditions deteriorate significantly.
3) Stationary holding furnace for smelting light alloys The furnace in (1) and (2) above has an open lid and preheats the material by the flame that erupts. However, it is not necessary to do this for special holding furnaces, but to try to reduce smoke exhaust from the top by improving operating conditions, and the chimney smoke exhaust method is adopted.
(2) Combustion device
At present, there is one turbine blower and one turbine fan for copper alloy crucible furnace widely used, the former is used to provide primary air, and the latter is to provide secondary air. The outstanding feature of this device is that it is either used to increase the melting speed or to control the melting atmosphere. The same method is used when burning heavy oil and gas. In addition, a rotor nozzle with a nozzle and a blower is integrated, which makes it difficult to control the atmosphere in the furnace, but it is lightweight, easy to move, and inexpensive except for special nozzles.
(3) The controlled atmosphere in the furnace during melting
When melting copper alloys, the atmosphere in the furnace has a great influence on the molten metal, especially the easy absorption of hydrogen and the reduction of the quality of the molten liquid.
The atmosphere in the furnace has a reducing atmosphere and an oxidizing atmosphere, the former refers to the high concentration of carbon monoxide () and hydrogen () in the furnace, and the latter refers to the high concentration of oxygen (), so the oxidation of the molten solution is significant. In order to control the atmosphere in the furnace between the two, it is necessary to maintain a low concentration of sum. At present, the C characteristic value is generally used as a rough measurement benchmark. The characteristic value is defined as: characteristic value = .
In other words, the air excess coefficient of a heavy oil furnace is slightly larger than that of a gas furnace, otherwise it cannot be completely combusted. This saves the discussion of the actual operation of the furnace, but it is important to understand the characteristics of each furnace, especially the characteristics of the atmosphere in the furnace, which is extremely important for the production of good quality products.