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Powder coatings manufacturing process
Powder coatings manufacturing process The process of powder coatings production includes the following steps: Distribution of raw material Pre-mixing of raw material Extrusion (mixing of melted raw materials) Cooling and crushing the extruder’s output Grinding , classifying, and controlling of the particles Packaging Pre-mixing of raw materials In this step, the distributed raw materials of each production unit will be mixed based on the guidelines and formulization of research and development unit in order to have a homogeneous mixture under specific time conditions. Extrusion The homogeneous mixture of raw materials will be melted and mixed in the extruder machine under the pressure of spiral driver and temperature of electric bars. Then , the homogeneous melted mixture will come out of the extruder while controlling the temperature of different parts of the extruder . The cooling belt The melted mixture will be poured on the cooling rollers at the temperatures between 7 C and 10 C ,formed as sheets ,carried toward the crusher through the cooling belt, and finally ,changed into chips and prepared for grinding . Grinding and sifting The produced chips at the end of cooling belt will be transferred into a mill with a pin disk. The controlling and size measuring of the ground particles will be conducted by a classifier ; the size of output particles of the mill will be measured through checking the speed of the classifier ,the speed of mill’s router and remaining of the chips inside the mill, and controlling the air volume and the temperature of the conveyer of ground powders. Based on their sizer, the output powders of the classifier and the mill will be categorized into three parts: The part of very small particles ,smaller than 10 micron , will be separated in the silicone and transferred into a container of small particles and dusts ; the remaining particles will be transferred into a sieve located at the bottom of the silicone. The ultimate product will be packaged based on the size of the net ; the net separates the inadequate and big particles. Finally , those big particles will be sent back into the mill once again through a channel devised near the sieve . In the process of coatings circulation , an additive will be added to the coating during its grinding in the mill . Quality control unit The quality control unit, founded to control the quality of products , takes out soome samples during various stages of production , such as coating chips, coatings,and coating powders , and runs various experiments using modern laboratory equipments to control the expected technical features and ensure the quality of output products.
Powder coatings curing process in the Oven
Powder coatings curing process in the oven consists of three stages. First,the solid particles are melted,then they combine together ,and finally they form a uniform film or coating over the surface . Maintaining low viscosity of the coating for an adequate time is very significant to have a smooth and even surface. Having decreased during the curing process, viscosity tends to increase as soon as the reaction (gelling )begins. Thus ,reactivity and heat temperature have a significant role in creating aRead More …
Tests of powder coatings
Tests of powder coatings Surface Characteristics Test Method Procedure (s) Primary Test Equipment Surface Characteristics Smoothness PCI # 20 Smoothness Standards Gloss ASTM D523 Glossmeter Color ASTM D2244 Colorimeter Distinctness of Image Visual Observations Contrast Ratio PCI #3 Special Substrates, ASTM D2805 Reflectance Instruments Physical Characteristics Physical Test Primary Test Equipment Characteristics Procedure (s) Film Thickness ASTM D 1186 Magnetic Film Thick Gauge, ASTM D1400 Eddy Current Induce Gauge Impact ASTM D2794 Impact Tester Flexibility ASTM D522 Conical or Cylindrical Mandrel Adhesion ASTM 2197 Balanced-Beam Scrape-Adhesion, ASTM D3359 Cross Hatch Cutting Device and Tape Hardness ASTM D3363 Calibrated Drawing Leads or Pencils Abrasion Resistance ASTM D4060 Taber Abrader and Abrasive Wheels ASTM D968 Edge Coverage ASTM 296 Standard Substrate and Micrometer Chip Resistance ASTM D3170 Gravelometer Test Method Procedure(s) Primary Test Equipment Environmental Characteristics Solvent Resistance MEK or other Stain Resistance ASTM D1308 Standard Reagents Chemical Resistance Immersion or Spot Tests Humidity ASTM D 1735 Standard Water Fog ASTM D2447 Chamber, Test Chamber 100% RH at 100F Salt Spray ASTM B117Read More …
How to prevent powder coating caking
How to prevent powder coating caking Different resins having different glass transition temperatures , such as epoxy and polyester resin has a glass transition temperature of about 50 degrees Celsius, lightening agent ( 701 ) has a glass transition temperature of about 30 degrees Celsius, the liquid leveling agent in minus degrees Celsius. The larger the amount of material with low glass transition temperature the powder coating formulations contain ,the lower the glass transition temperature will become .Glass transition temperature is measured by a dedicated large equipment, powder coating manufacturers generally do not have this expensive equipment, and in the production process they can not grasp the glass transition temperature of powder , therefore , in the production of the powder system positioned about the glass transition temperature of 40 ° C , the temperature of the powder coating caking as safe temperature . Then in the production ( and product storage and transportation process ) as a standard , close to and above this temperature the relevant personnel must strengthen sampling of product caking .Especially in Summer,the caking problem occurs easily due to the rising temperature, then how to prevent powder coating caking ? First, powder coating at a certain temperature agglomeration is a law of nature. To prevent caking powder coating , production must milling , packaging, storage, transportation, and so the whole process, powder coating products in its glass transition temperature. According to this view is the following solutions: In the polyester resin production , the selection of some of the glass transition temperature can increase the alcohol or acid , or reduce the use of resin, the glass transition temperature to reduce the amount of alcohol to increase the glass transition temperature of the polyester resin . In the powder coating formulation to reduce low glass transition temperature polymer is used in an amount , such as leveling agents and lightening agent to ensure that the powder coating system does not decrease the glass transition temperature . Production, broken down on the strip sheet material should be sufficiently cooled before entering the milling process , milling should be appropriate to reduce the feed rate , increasing the lead air damper , inlet air to control the installation of air conditioning milling temperature . However, if the former mill crushed flakes stuck atop cooling , the latter would not have the means to play a good role , consider crushed flakes on the method of forced cooling cryogenic treatment, which is more effective than retrofitting . Further, anti-caking additives may be added , such as nano- silica (VK-SP15) or nano- aluminum oxide (VK-L20M) powder to prevent adhesion between powder particles , anti-caking agents are generally simultaneously and broken flakes milling best. All in all ,In the production,the relevant personnel must make a strict sampling to avoid powder coating caking .
Ukraine powder coatings account for 2% in the paints and coating market
Ukraine powder coatings account for 2% in the paints and coatings market. The demand for paints and coatings in the Ukraine is estimated at 355,000 tonnes per year, with a per capita consumption of 7.7 kg. According to “Directory of Paint Manufacturers 2011 – Central and Eastern Europe”, a recently published study by Chem4cee Handels GmbH, about 50 manufactures are operating on the Ukrainian market producing 300,000 tonnes per year. The structure of the market in terms of volume isRead More …
See you in Thailand-Asia Pacific Coating Show 2013
Jinhu Color Powder Coating will attend Asia Pacific Coating Show 2013 in 12-13 September,2013 Exhibition: Asia Pacific Coating Show 2013 Date:17-18 July 2013 Address:Bangkok ,Thailand Please contact us for more information if you come .
Phosphate coatings-the recognised pre-treatment for steel substrates
The recognised pre-treatment for steel substrates just prior to application of powder is phosphating which can vary in coating weight. The greater the conversion coating weight the greater the degree of corrosion resistance achieved; the lower the coating weight the better the mechanical properties. It is therefore necessary to select a compromise between mechanical properties and corrosion resistance. High phosphate coating weights can give trouble with powder coatings in that crystal fracture can occur when the coating is subjected toRead More …
Considerations for Choosing a Coolant for metal working process
Different metal working processes have varying cooling and lubrication needs. Coolants have many properties that increase their efficiency, extend their life, and minimize the potential to damage tools and products. Therefore, when choosing a coolant, many factors need to be considered. These considerations include: Tramp oil rejection Ability to settle out solids Bacterial resistance Corrosion and rust resistance Emulsification capability Foaming nature and resistance Optimal coolant life Longevity of coolant as measured against current industrial standards Cost of coolant ChemicalRead More …
Paint Removal
When repainting a part,prior to application of the new paint coat the old,paint often must be removed. The waste reduction assessment should start by examining what causes the need for repainting: inadequate initial part preparation; defects in coating application; equipment problems; or coating damage due to improper handling. While no process is perfect, reducing the need for repainting has a direct effect on the volume of waste generated from paint removal. Once the need for paint stripping has been reducedRead More …
D5 Creation