Optimizing Ceramic Sanitaryware Production: A Simple Guide to the Manufacturing Process
Body Preparation
The initial phase in the manufacturing or production process for sanitaryware is body preparation. Slip is created in this procedure by combining feldspar, China clay, silica, and ball clay. We refer to this composition as the Tri-axial body. comprise flux, filler, and body former. Plastic body former is needed to provide strength when the sanitary ware is still in the green stage. The filler is made of non-plastic substance that will become stronger after burning. A non-plastic substance called flux is supplied to the body during firing in order to lower the body's fusion temperature point. All raw components are combined in the right order and heated to the necessary temperatures.
After slip preparations, the rheological parameters of fluidity, slip thickness after one minute and five minutes, and liter weight are often checked.
The composition, climate, casting (Bench casting, high-pressure casting, low-pressure casting for sanitaryware and other items), and necessary casting rate will all affect these factors.
A combination of virgin, runoff, and scrap slip will make up the supply slip. Additionally, this composition will change based on the desired casting rate and the availability of scrap slip.
Slip will be sent to slip storage silos after it has been manufactured in accordance with the necessary parameters. Slip will be provided to the casting department for casting whenever it is needed.
Glaze Preparation
The glaze was ready for spraying throughout this procedure. Preparing the glaze and the body happen simultaneously. Various glaze colors will be produced based on the specifications. The raw materials zircon, feldspar, quartz, calcite, china clay, and zinc oxide are used to prepare glazes. Before being removed from the ball mill, raw materials are ground and their particle sizes are measured. Ball mils use alumina balls because of their strength. To eliminate iron particles and remove coarse particles, the glaze will be run through sieves and magnets. To verify the final color of the glaze, sample spraying will be carried out and then burned. A laboratory should authorize the glaze before it is utilized in production or manufacturing. To provide the glaze the necessary qualities, it will be combined with a binder before being supplied to the spraying. To obtain the right spray, density, drying time, fluidity, and viscosity are maintained.
Moulding/Mould Preparation
This procedure will provide the necessary size and form mold for casting. Case moulds are sent from the section that makes cases to the section that moulds them. Cast plaster molds were utilized with case moulds. Plaster of Paris and water are mixed in the appropriate ratio to prepare the mold. The chemical formula for plaster of Paris is CaSO4.1/2 H2O. Plaster and water should typically be mixed at a ratio of about 4:3. This ratio may differ slightly depending on the plaster's purity, the mold's needed strength, etc. It will even more for a single ware with up to four molds for complicated models. The mold will be dried in a dryer once it has been prepared in order to eliminate any remaining water. In order to prolong the mold's life, this stage is essential. Because of its absorption capabilities, the plaster used to create molds is referred to as beta plaster. Typical castings will be made using a plaster mold. Casting at high pressure is done using a resin mold.
Casting
For hygienic gear, several casting kinds are available. For sanitaryware, they include standard bench casting, battery casting, beam casting, low-pressure casting, and high-pressure casting. Every casting has benefits and drawbacks. Slip is put into the mold and allowed to form the casting layer on the mold; this is the identical casting procedure for all forms of casting. After that, a drain hole is used to empty the extra slide. The cast ware is now allowed to dry before being taken out of the mold. Currently, the merchandise referred to as greenware. Before being dispatched to a drier, this greenware is let to dry at room temperature for one to three days. Greenware should be finished for smooth joint edges, minor fractures, pinholes, poor finishing, etc. before it dries. When the ware is prepared, it will be sent to a dryer to finish drying. Before drying, the greenware's moisture level will range from 22% to 12%.
Drying
The casting of the green piece will be sent to Control for spraying through a dryer. By eliminating the water that had been mechanically mixed from the pottery, Drier's Green MOR increased. After drying, greenware's moisture level will range from 1.5% to 0.5%. Between 6.5 and 12 hours will pass during the drying process. A dryer might be a tunnel drier or a batch drier. The batch drier will be simultaneously loaded and discharged. Ware will be continually fed into the tunnel drier and continuously released at the other ends. Heat will be applied gradually from room temperature to 110–120 degrees Celsius. The item will decrease in size and lose weight during this procedure.
Control & Spraying
The merchandise will be examined for flaws in this area. Depending on the flaws, defective goods may be accepted for repair or rejected. Typically, one team will handle both the spraying and control departments. Kerosene is used to identify product flaws. Ware that has been thoroughly inspected will be delivered to the spraying area.
The glaze that was obtained from the glaze house will be sprayed. Depending on the production schedule, different colors are sprayed on the goods. Spraying will be done by robotic or manual means. Spraying applies a glaze layer of 0.8 to 1.6 m on the goods according on the specifications. After the spraying process is finished, it is given a few minutes to dry. Next, the logo is applied to the product using decal or screen printing. These days, a powered printing machine is used to print logs after fire as well.
Firing
Kiln car loaded with sprayed pottery. A vacuum or air blower is used to remove dust and other contaminants from the product. Typically, The highest temperature in the kiln will be 1250 C. While both shuttle and tunnel kilns can be used for firing, tunnel kilns are more frequently used. A refiring shuttle kiln is utilized. The three zones of a sanitary ware kiln are the fire, cooling, and preheating zones. Water has been extracted from the ware by a chemical and mechanical process in the preheating zone. All of the basic materials fuse together at the firing zone, resulting in an evenly fused glaze. To produce a glossy surface, rapid cooling is applied in the cooling zone. The product will be moved to the sorting area after it has fired.
Sorting
At this point in the procedure, every item that comes out of the kiln is examined and arranged based on defects. The merchandise will be sent to the packing department for packaging if it is free of faults. Should the ware have little flaws such as pinholes, cold fill will be used to fix it. It will be sent to the refire section if it has a light glaze, is wavy, or is blibbed. Locate every sanitaryware flaw. It won't be accepted if there is a crack. Maintaining standards requires the importance of this quality check. In addition, a random sample will be taken for the load, smoke, leak, and flush tests.
Refire/Rework
For small repairs, all repairware will be routed to the rework department. Every item is dispatched to the tunnel kiln based on the flaw. It will be inspected and graded again after it has been fixed and fired once more. It will be shipped to packaging if quality standards are satisfied. It will be repaired in the refire section if it needs to be fixed again. Large and damaged goods will be placed in the rejected section. Usually, these are fractured or warped parts.
Packing
It is the last phase of the production/manufacturing process for sanitary items. After meeting quality criteria, all sanitary goods are packaged and sent to the warehouse.
In summary
Apart from the aforementioned divisions, the manufacturing/production process of sanitaryware also include the Lab, New Product Development, and Mold & Case Making sections. The manufacture and production process for sanitary items is not fully represented by this method. Every step is covered in full in another section.