Today, as a toilet manufacturer, we will reveal to you the mud preparation process of ceramic industrial products, mainly from the following aspects:
1. The process of mud preparation process
2. Process control of mud performance
3. Explanation of several basic concepts of mud
1. Ceramic Sanitary Ware Mud preparation process
The mud preparation process of LORY ceramic sanitary ware manufacturing factory is as follows:
Raw materials enter the factory for inspection→selection→weighing into the mill→slurry inspection→high mixing tank (add clay for the second time and stir)→sieve and remove iron→stale→qualified debugging→for molding
(1) LORY ceramics manufacturing factory currently uses feldspar, quartz, clay, feitian mud, mixture, cyanide, clinker, and talc as raw materials for preparing mud. The additives used are soda ash and silicon metasilicate pentahydrate. (Click here to learn more about Ceramic Sanitary Ware raw materials )
(2) Raw materials can only be used after passing the inspection after entering the factory. Raw material testing includes physical performance testing and chemical analysis.
The physical performance test judges whether it meets the requirements through the appearance, shape, color, and post-burning condition of the raw materials.
Chemical analysis is the detection of the chemical composition of raw materials, including the detection of nine items: SiO2, Al2O3, K2O, Na2O, FczO3, TiO2, CaO, MgO, and H2O.
(3) The equipment used to prepare mud in LORY ceramic sanitary ware manufacturing factory is a ball mushroom machine, and pebbles are used as grinding media (ie ball stones). Material: ball stone: water ≈ 1:2:0.45, after grinding for a certain period of time, take a sample and test, after testing the fineness meets the requirements, it can be put into the high stirring pool.
(4) The clay is added to the high-stirring tank for a second time and stirred for 4 hours, and then sieved and iron removed. After the mud is sieved and iron removed, it is put into the stale pool, and it is used for molding after being stale.
2. Process control of mud performance
Mud and glaze slurry are the basis of molding and firing. There is a saying in the ceramic industry that “the raw material is born and the firing is the death”. Controlling the quality of the mud is the main factor to ensure the quality of the product.
(1) The fluidity of the mud is better and the water content is less.
The water content of the mud used in the LORY ceramic manufacturing factory is 30% to 33%. If the water content is too high, to obtain a green body with a thickness that meets the requirements, the mud stays in the model for too long, and the non-plastic raw material particles will settle and the mud will be stratified. , resulting in waste. If the water content is too small, the fluidity of the mud will be poor, and it will not be able to fully fill all parts of the model, which will easily produce dust and waste products.
(2) The permeability of the mud should be appropriate, so that the grouting time can be shortened, the labor productivity can be improved, and the pouring speed will not be too fast, which will make it difficult to grasp the thickness of the green body and bring difficulties to the operation.
(3) The shrinkage should be small, and if the shrinkage is too large, it is easy to cause deformation and cracking.
(4) It has sufficient dehumidification performance, so that the injection parts are easy to dry and form a solid green body. After the mold is removed, the green body will not collapse under vibration, and can still maintain its original shape.
(5) The less air bubbles in the mud, the better, so as to reduce the air bubble limit in the injection parts and improve the green strength.
(6) The empty slurry performance of the mud is better. After the residual mud is discharged, the inner surface of the injection part is smooth without mud wisps, because the mud wisps may cause drying and cracking, so the remaining mud is required to have good drainage.
The physical and technological properties of the mud such as density, viscosity, fluidity, thixotropy, permeability, and stability are controlled by the amount of strong plastic clay, mud fineness, moisture content, aging time and mud temperature.
The amount of strong plastic paste is small, and it is easy to obtain mud with fast water evacuation, fast drying, and fast demoulding, but the formed body is often not dense in structure, poor in strength, and prone to cracks; Cause the thickness of the injection parts to vary and delamination.
The fineness of the mud varies with the complexity of the size and shape of the product.
Under the premise of ensuring fluidity, the water content of the grouting slurry should be as low as possible to reduce the shrinkage of the green body, reduce the water absorption of the plaster mold, increase the drying speed of the model, shorten the service life of the model and prolong the service life. The water content is controlled by Add the right amount of electrolyte to adjust. The most common electrolytes are sodium carbonate and water glass. The addition of the former can obtain slurry with fast water powder evacuation and fast pouring speed, but the green body is loose and weak in strength. Water glass can obtain a green body with higher density and stronger strength body.
3. Several basic concepts of mud
a. Fineness:
Fineness refers to the particle size distribution of the mud. It is typically measured using techniques like sedimentation or laser diffraction. Finer particles improve the plasticity and workability of the mud, but excessive fineness can lead to increased viscosity or difficulties in processing.
b. Fluidity:
Fluidity, also known as workability or flowability, measures the ease with which the mud flows. It is influenced by factors such as water content, particle size distribution, and additives. Proper fluidity ensures easy shaping and forming of ceramic products.
c. Thickening Coefficient:
The thickening coefficient is a measure of the increase in viscosity of the mud over time. It indicates the stability of the slurry and its ability to resist settling or separation. Higher thickening coefficients indicate better stability.
d. pH Value:
The pH value of the mud indicates its acidity or alkalinity. It is an important parameter for controlling the stability and chemical reactions within the slurry. pH adjustment may be necessary to optimize the properties of the mud and prevent issues like flocculation or excessive deflocculation.
By carefully controlling these aspects of the mud preparation process and understanding the basic concepts of mud, ceramic manufacturers can produce consistent and high-quality industrial products.
