(Take the quenching Furnace of Masteel Hub Plant as an example)
– To provide customers with the most professional thermal insulation solutions –
– Overview of Masteel ring quenching furnace –
Masteel annular quenching furnace is a continuous operation furnace, fuel is mixed gas, burner is staggered on the inner and outer ring wall, normal furnace temperature is 1000~1100℃, weak reducing atmosphere, micro positive pressure operation.
– Considerations before modification: comparison between heavy traditional lining and light ceramic fiber lining-
Traditional lining structure: firebrick and heavy castable structure
Disadvantages of traditional lining structure:
1. High volume density leads to serious deformation of furnace steel structure.
2. High thermal conductivity of the furnace lining and poor thermal insulation effect result in serious energy waste of the cold surface of the furnace (up to 150~170℃) and poor operating environment for workers.
3, the furnace lining is difficult to overcome the annular furnace inherent inner and outer wall expansion, external wall expansion defects.
4, poor thermal sensitivity, to the annular furnace microcomputer operation to bring a certain negative impact, to a certain extent affect the quality of products.
Ceramic fiber properties:
1. Small volume density, folding module lining weight is only 20% of light heat resistant lining.
2. Small heat capacity. The heat capacity of ceramic fiber material is 1/9 of that of light and heat-resistant lining, which can reduce the heat loss of furnace lining.
3. Low thermal conductivity. The heat transfer rate of ceramic fiber material is 1/7 that of light clay brick and 1/9 that of light heat-resistant lining, which can greatly improve the thermal insulation effect of furnace lining.
4. Good heat sensitivity, better able to adapt to automatic control of heating furnace.
Aiming at the above problems existing in the annular furnace and the performance characteristics of ceramic fiber refractory materials, the designers of the company and the technicians of the hub factory unanimously decided to make a bold attempt to transform the lining after careful deliberation and demonstration.
Choose new energy-saving furnace lining structure: ceramic fiber blanket and folding block composite structure
– Heat preservation structure after energy saving renovation –
Reformed lining structure:
Thermal insulation solution for furnace top lining: laminate – modular compound furnace lining structure;
Insulation layer: the total thickness is 350mm;
Backing layer: Ceramic fiber blanket RDGW-312, thickness 50mm;
Hot surface: ceramic fiber mold RDGW-589 with a thickness of 300mm;
The ceramic fiber modules are arranged in a “pawn type” arrangement.
Interlayer compensation blanket: ceramic fiber blanket RDGW-512, fixed with “U” type heat-resistant steel nail;
In order to meet the special structural requirements of the annular furnace top, the ceramic fiber module is made into wedge-shaped structure and the anchoring structure is slide type.
– Energy-saving effect of furnace lining transformation –
The whole fiber lining structure of the ring furnace of Masteel hub plant is the first case in China. The success of its operation is directly related to the feasibility of the design party’s scheme, and the success of the transformation of the hub plant is also related to the promotion of ceramic fiber products in the ring furnace and the whole metallurgical industry. Therefore, the ignition and operation of the furnace lining renovation project of Masteel Hub plant have attracted the attention of all relevant parties. The most advanced detection means have been used to measure the furnace operation. The results are as follows:
|Parts of the||Chamber of a stove or furnace||Cold noodles around the burner||Look at the cold side around the fire hole||Conventional grim||Raw cold surface temperature|
|First temperature measurement||600℃||58.1℃||53.5℃||49.3℃||–|
|The second temperature measurement||750℃||62.3℃||57℃||52℃||–|
|The third temperature measurement||850℃||66.5℃||62.1℃||57.8℃||–|
|The fourth temperature measurement||1100℃||80.5℃||75℃||61℃||160℃|
– Technical advantages –
Wedge-shaped module: aluminum silicate fiber module is made into wedge-shaped structure. Although it brings some inconvenience to the processing of the module, only when the module is processed into the required structural shape can the integrity and tightness of furnace lining be fully guaranteed. Avoid excessive influence of construction technical factors on the effect of furnace lining to ensure smooth construction (such as the use of square module, the side close to the inner ring is forced to compress due to arc length, easy to cause one end of the module damaged or folded surface fracture, damage the module structure, affect the insulation effect of the module).