Machine pressure forming method is currently the most used in the production of
refractories ball forming method. The method uses a pressure ball machine and a steel mold to press the prepared
refractory material into a sphere. Because of the general machine pressure forming refers to the water content of 4% to 9% of the semi-dry material forming method, which is also called semi-dry forming. The method commonly used equipment friction brick press, lever press and hydraulic press and so on.
Machine pressure forming process is essentially a ball material within the particle-intensive and air discharge, the formation of dense sphere process. The ball-forming fire-resistant ball has the advantages of high density, high strength, small drying shrinkage and small shrinkage, easy control of fire-resistant ball size, so this method is the main part in
refractory firebrick ball production. In order to obtain a dense sphere during press forming, sufficient pressure must be applied to the pellet. The size of the pressure should be able to overcome the internal friction between the pellet material, to overcome the external friction between the pellet and the mold wall to overcome the
insulating castable moisture, particles and fill in the mold caused by uneven pressure distribution Uniformity.
The ratio between the three depends on the ball material dispersion, particle composition, ball material moisture, the size and shape of the sphere. Although the relationship between pressure and the densification of the sphere can be calculated by a number of theoretical formulas, such as the variation of the porosity of the sphere with pressure in logarithmic relation, the experimental method is usually used to determine the pressure per unit area of the sphere, Brick machine should have the total pressure.
Mechanical forming of the ball material requirements in addition to water should have a certain range of fluctuation, its particle size also has certain requirements, such as should have a reasonable grain size ratio, bulk density as large as possible. General critical particle size of 3 ~ 5mm, less than 0.088mm of fine powder content should be 35% to 45% range. The most common defects in machine-formed fire-resistant spheres are the crack and layer density. Spallation is the formation of pressure in the vertical direction of the pressurized layer of cracks. Ball material moisture is too high, too much powder, too little bonding agent and pressure will lead to the production of spall.
Therefore, in the production of these parameters must be controlled. Layer density phenomenon that the shape of the fireball after the density along the pressure direction of the inverter. By the above one-way pressurized
insulating refractory cement ball is generally dense under the sparse, the same level is dense in the outer sparse. This is due to the friction between the pellet material and the ball material and the friction between the mold wall caused by the pressure decrease. Double-sided pressure and the wall in the mold coated with lubricating oil to reduce the external friction of the method can reduce this phenomenon and reduce the porosity of the sphere.
Selection of molding equipment should be based on the quality requirements of refractory balls, size and production volume for comprehensive consideration. General refractory ball with a simple fireball or shape, quantity, quality requirements of the general products, the choice of production efficiency of the high pressure ball machine; high quality requirements of the fireball can be nominal pressure not less than 2000K N friction Pressure ball machine.
Henan Xinmi Changxing Refractory Material Co., Ltd. Located in Henan Province,China.ChangXing's product portfolio covers shaped products such as refractory materials,refractory brick, refractory castable,refractory nozzle, ceramic fiber, slide gate, etc; unshaped products including repair, construction and casting mixes and mortars.exported to more than 20 countries, such as Thailand, Indonesia, Pakistan, Saudi Arabia, South Africa, Turkey, Iran, Iraq and so on.
