A coating is a process in which layer of polymer or any material in liquid form used for depositing or covering the surface of the substrate. As per the Wikipedia the purpose of coating is decorative, functional or both. Decorative coating is done to achieve the aesthetic look and feel of material i.e. coating or painting on the fabrics with some artistic manner, on the other hand functional coating is applied achieve the adhesion, wetability, corrosion resistance, wear resistance, or water resistance.
The science of coating requires the understanding of the two phenomenon liquid flow and surface chemistry that deals with the solid to liquid relations. Study of viscosity and changed in the shape of liquid is very important in the process of coating.
Coatings are defined as mixtures of various materials. The materials are classified into four categories:
Techniques of the Coating:
Various coating techniques help in achieving the coating width of from thickness of some microns to mm, various coating techniques are as follows:
- Gravure Coating Machine
- Reverse Roll Coating Machine
- Knife Over Roll Coating Machine
- Air Knife coating
- Metering Rod (Mayer Rod) Coating Machine
- Slot Die Coating Machine
- Curtain Coating Machine
- Immersion/Dip Coating Machine
- Hot melt Coating Machine
- Web Coating Systems
- Fabric Coating Machine
You can ask the experts such as KERONE those are pioneer in manufacturing and designing of various type of the coating machines and plants. We can be reached at email@example.com .
The paper and paper products plays more substantial role in the day-to-day life of the human, its usage are increasing every day in as newspapers, magazines, envelopes, books & diaries, stationeries, packaging and etc. the usage of paper and paper related products have become nearly unlimited. The increasing application has increased the demand of quality paper, majorly the paper quality is defined in terms of its smoothness, glossy finish, printability, uniform thickness and moisture contain.
The increasing demand of the paper the manufacturers wanted to have the paper manufacturing machines to produce higher quality paper, increase productivity, reduction in the waste, safe and improved process control. The paper manufacturing and paper coating process is known as one of the major dewatering process, which requires removal of all even a small amount of water also by the way of evaporation for the quality paper and coatings. The paper machine consist of the four sections Forming Section, Press Section, Drying Section, Calender Section. Wikipedia explains the sections as follows:
- Forming section, commonly called the wet end, is where the slurry of fibres filters out fluid a continuous fabric loop to form a wet web of fibre.
- Press section where the wet fibre web passes between large rolls loaded under high pressure to squeeze out as much water as possible.
- Drying section, where the pressed sheet passes partly around, in a serpentine manner, a series of steam heated drying cylinders. Drying removes the water content down to a level of about 6%, where it will remain at typical indoor atmospheric conditions.
- Calender section where the dried paper is smoothened under high loading and pressure. Only one nip (where the sheet is pressed between two rolls) is necessary in order to hold the sheet, which shrinks through the drying section and is held in tension between the press section (or breaker stack if used) and the calender. Extra nips give more smoothing but at some expense to paper strength.
The most critical part of the paper making process is drying the paper post press section to leave around 6% of the moisture contain within paper, hence the selection of the dryer and drying technology plays very vital role in total paper production system. In the dryer section, the paper entanglement passes over rotating; a cast iron cylinder which was heated by the means of heat transfer mechanism such as Convention, Conduction and/or Radiation and the most of the remaining water is removed by evaporation. When the paper leaves the dryer section its solid content has increased to about 90-95%. Thermal energy transferred from the heater is used for the dewatering of the paper in the dryer section.
Since the drying is critical in the entire paper production process as overlooking its criticality by the paper manufactures and/or plant operators may results in improper paper quality of paper, increased waste and reduced production. Hence the choice of the drying technology and dryers needs to be done properly by consulting with the leaders in the field of heater and heating technologies such as KERONE.
KERONE has been serving the paper and other manufacturing processes with its quality and technically superior innovative product quality since last 40 years. We at KERONE is have team of experts to help you with the your need of heating system from our wide experience. For any query write us at firstname.lastname@example.org .