Refractory products and properties for ceramic kilns
January 22, 2021
1. Cordierite - Mullite Kiln Material
A Cordierite - Mullite Kiln Material
Primary kiln furniture refers to the construction of burning space of the shed, pillars and other refractory products. A secondary kiln tool is a small kiln tool placed directly on a primary kiln tool to support or protect the burning product. Cordierite - mullite materials have a variety of complex, different shapes of primary and secondary kiln furniture.
Cordierite-Molai stone shed board is divided into porous shed board, hollow shed board and so on. The advantage of porous shed plate is to reduce the heat absorption of kiln furniture and to facilitate convection heat transfer up and down the shed plate. The advantages of hollow shed plate are that it reduces the quality of the shed plate and increases the heat transfer area, which is beneficial to reduce fuel consumption, shorten the firing time and alleviate the damage caused by the sharp change of temperature. The biggest advantage of hollow shed plate is that it can significantly improve the high temperature bearing capacity of products. Thus, it is beneficial to reduce bending stress and prevent deformation of shed plate.
The condition for the correct use of the hollow plate is that the longitudinal direction of the beam is perpendicular to the longitudinal direction of the hollow column in the plate, and the beam should be properly indented from the edge of the shed plate to reduce the span.
Properties of B Cordierite-Mullite Kiln Material
China has been able to produce high-level cordierite-Molai stone kiln products. Due to insufficient size, the thermal shock resistance of kiln materials can not be tested by current standards. The kiln furniture is often cut into strip test bodies of the same size, the same heating and cooling methods are used for thermal shock, the variation law of flexural strength before and after thermal shock is measured, and the thermal shock resistance is evaluated by contrast method.
2. silicon carbide materials
A production line of silicon carbide and silicon nitride combined with silicon carbide products has been set up jointly with German companies in China with a production capacity of 200 t/a. The products include: roller rod, cross beam, burner tube, cold air tube, thermocouple casing, temperature measuring tube and special structural parts, etc., which can prepare up to 3500 mm roller rod, square beam and 700 mm*800mm large size shed plate.
Weifang Huamei Fine Technology Ceramics Co., Ltd. and Germany FCT- Fine Ceramics Technology Co., Ltd. jointly built a reaction sintered silicon carbide products production line, the annual design and production capacity of 200 t, The main products are roller rod, beam, shed plate, burner sleeve, quench pipe, thermocouple protective pipe, sagger, crucible, sand nozzle, power station and other large-scale boiler desulphurization nozzles, seals and special-shaped high-temperature, wear-resistant, corrosion-resistant parts.
3. Aluminium Silicone Material
Small and medium mullite-corundum products are produced in many factories in China, some factories have 1800℃ of inverted flame kiln and 1000 t of friction brick press. Large mullite-corundum products such as electronic ceramic industry push board still need to be imported, large size mullite-corundum material production needs higher technology and high equipment conditions. If high grade raw materials are used, iron, large tonnage press and high temperature kiln with uniform temperature are not brought into the processing, and suitable fixture materials are found to prevent the products from being deformed in the process of burning.
4. ceramic roller
The special treatment of alumina is used as the main raw material, the auxiliary material is added, calcined by isostatic pressing and specially designed kiln, and then the roller rod is made by precision machining. The performance indexes are as follows: straightness less than 0.1 of total length; thermal stability :1350℃ to normal temperature more than 5 times; bending strength greater than 45 MPa; maximum operating temperature :1350℃; water absorption less than 10; linear expansion coefficient (25~1200℃):6.0*10¯6(K¯1).
5. refractory fibre products