Manufacturing/Production of Sanitary Ware
From body preparation to packing, the sanitary ware manufacturing/production process consists of ten steps.
Section I: Table of Contents
Preparation of the Body
Preparation of the Glaze
Casting Drying Control & Spraying Moulding/Mould Preparation
Firing sSorting
Refire/Rework sPacking sConclusion
sanitary ware manufacturing manufacturing process sanitary ware manufacturing manufacturing procedure
Preparation of the Body
The initial phase in the Sanitary ware Manufacturing/Production process is body preparation. Slip is created in this procedure by combining Ball clay, Silica, China clay, and feldspar. This structure is known as a Tri-axial body. Body former, filler, and flux are included. The body former is a plastic material that is necessary to provide strength during the green stage of sanitary goods. The filler is a non-plastic material that will provide strength following fire. Flux is a non-plastic material that is introduced to the body during firing to lower the fusion temperature point. All raw ingredients are properly combined and brought to the desired physical characteristics.
After slip preparations, theological criteria such as fluidity, thixotropic of the slip after 1 minute and 5 minutes, and lighter weight are usually examined.
These characteristics will change according on the composition, climate, necessary casting rate (bench casting, high-pressure casting, low-pressure casting for sanitary ware, and others).
The supply slip will be a combination of virgin, runoff, and scrap slip. This composition will also change depending on the availability of scrap slip and the necessary casting rate.
Slip will be sent to slip storage silos once it has been prepared according to the specified parameters. When slip is necessary, it is given to the casting department for casting.
Preparation of the Glaze
The glaze is prepared for spraying in this process. The preparation of the body and the preparation of the glaze run concurrently. Various glaze colors will be created according on the requirements. Zircon, feldspar, quartz, calcite, china clay, and zinc oxide are the primary materials utilized in glaze manufacturing. Before unloading from the ball mill, the raw materials are pulverized in a ball mill and the particle size is checked. Because of its robustness, alumina ball is utilized in ball mils. The glaze will be sieved and magnetized to remove coarse particles and iron particles. To determine the final color of the glaze, sample spraying will be performed and fired. Before being used in manufacturing/production, the glaze should be approved by a lab. To give the desired qualities, the glaze will be combined with a binder before being supplied to the spraying. To get the desired spray, density, drying time, fluidity, and viscosity are all maintained.
Moulding/Mould Making
This technique will provide the necessary form and size mould for casting. Case moulds are transferred from the case making department to the moulding section. Cast plaster moulds were utilized for case moldings. Mould is made by combining water and Plaster of Paris in the right proportions. CaSO4.1/2 H2O is the chemical formula for plaster of Paris. Typically, the plaster-to-water ratio will be around 4:3. This ratio may vary slightly depending on the purity of the plaster, the desired strength for the mold, and other factors. It will be even more for a single ware up to four moulds for complex models. Once the mould has been prepared, it will be dried in a drier to eliminate any extra water. This stage is critical for extending the life of the mold. Because of its absorbent qualities, the plaster used to make molds is known as beta plaster. In most cases, a plaster mold will be used. For high-pressure casting, a resin mould is employed.
Casting
For hygienic goods, various types of casting are available. They are sanitaryware bench casting, battery casting, beam casting, low-pressure casting, and high-pressure casting. Every casting has benefits and drawbacks. The casting procedure is the same for all forms of casting; slip is put into the mould and allowed to form the casting layer on the mould. The surplus slide is then evacuated via a drain hole. Casted pottery is now allowed to dry before being removed from the mold. The ware is known as greenware at this stage. This greenware is allowed to dry for one to three days at room temperature before being transported to the drier. Finish the greenware before drying to ensure smooth joint edges, correct minor cracks, small pinholes, poor finishing, and so on. When this ware is finished, it will be sent to the dryer to dry. The moisture level of the greenware before drying will range from 22 to 12 percent.
Drying
Control will receive the green piece form casting and spray it through Drier. By removing the mechanically combined water from the ware, Drier improved the Green MOR of the ware. The moisture level of greenware after drying will range between 1.5 and 0.5 percent. The drying time will range between 6.5 and 12 hours. A drier can be either a batch drier or a tunnel drier. The batch drier will be loaded and unloaded simultaneously. The tunnel drier will be continuously fed with ware and discharged at both ends. The temperature will be gradually raised from the atmosphere to 110 to 120 degrees Celsius. And ware will lose weight and shrink in size during this process.
Spraying and Control
In this step, the ware will be scrutinized for flaws. Depending on the faults, defective goods will be rectified or rejected. The control and spraying departments are usually managed by the same team. Kerosene is utilized to detect flaws in the goods. Properly checked goods will be sent to the spraying area.
The glaze from the glaze house will be used for spraying. Various colors are sprayed into products according to the production schedule. Spraying will be done manually or robotically. The glaze is sprayed on the goods in thicknesses ranging from 0.8 mm to 1.6 mm, depending on the application. After spraying is finished, it is allowed to dry for a few minutes. The logo is then printed on the ware utilizing screen printing or decal processes. Nowadays, log printing is done using a powered printing equipment after fire.
Firing
Sprayed porcelain is loaded into the kiln car. An air blower or vacuum is used to remove dust and other contaminants from goods. Typically, the maximum temperature of the kiln is 1250 C. Different types of kilns can be used for firing (shuttle kiln, tunnel kiln), with the tunnel kiln being the most common. For refiring, a shuttle kiln is employed. The sanitary ware kiln is divided into three zones: preheating, fire, and chilling. Water has been removed from the ware mechanically and chemically mixed in the preheating zone. At the firing zone, all of the raw materials are fused together, and the glaze is equally fused. Sudden cooling is used in the cooling zone to create a glossy surface. The product will be moved to the sorting section after it has been fired.
Sorting
All ceramics from the kiln are inspected and categorized according to the Defects at this stage of the process. If the product is defect-free, it will be sent to the packing area for packing. If the ware has small flaws, such as pin holes, it will be fixed with cold fill. If it has a faint glaze, is wavy, or has a glob, it will be sent to the refire section. Locate all sanitaryware flaws. It will be rejected if there is a crack. This quality check is critical for maintaining standards. In addition, random sampling will be performed for the flush test, smoke test, leak test, and load test.
Refire/Rework
For simple repairs, all repair items will be forwarded to the rework department. According to the flaw, every ware is required and transported to the tunnel kiln. It will be inspected and graded again when it has been fixed and fired again. If the quality standards are reached, it will be packed. If it needs to be repaired again, it will be repaired in the refire section. Major and irreparable goods will be routed to the rejected region. Typically, these are warped or cracked pieces.
Packing
It is the final stage in the manufacturing/production of sanitary items. All sanitary items that meet quality criteria are packed and shipped to the warehouse.