Follow us :

Plasticizing requirements for Ovens

time2013/12/07

Plasticizing requirements for Ovens

Two commonly used electrostatic spray oven, preheat the oven and plasticizing ovens that (if the production volume is small, can be an oven, preheat and plasticized workpiece that carried the same furnace at l spoon). Preheat oven role is initially cold spray at room workpiece heating the powder to achieve half plasticized state, when the workpiece is removed from the oven, then a second coating, this time due to the high temperature of the workpiece, called thermal spray habits. Some of the complex shape of the workpiece, the electrostatic shielding effect, the cold spray inside corner pockets easily adsorbed powder. However, the thermal spraying of the second club, belonging to the heat revolves role of these "shadow zones" of the adsorbent powders can, with the workpiece is heated, an insulating powder was reduced further to strengthen the electrostatic adsorption of the coating applied thick. The plasticizing effect of the oven, the workpiece is heated to bake the coating melt state, making a uniform plasticizer coating leveling. Two oven temperature control, according to the coating material may be used, the maximum temperature of the oven should be higher than the melting temperature of the material is about 30 degrees, while the furnace temperature uniformity requirements, temperature of the furnace is less than 3'C points This is the main point of the quality measure of the oven. If the heat throughout the different parts, there will be cooked or burned phenomenon, and caused some of the products of each coating color inconsistencies and other defects, directly affect the appearance and adhesion of the coating. Sometimes encountered such a situation: the workpiece from the surface treatment until the completion of the second spray is good, but after the final plasticized (or curing) after the apparent half-cooked or fire phenomenon, resulting in wasted, forced to rework. The reason is forced hot air circulation oven device failure, the furnace temperature too much. So, make sure the furnace temperature is kept uniform. Heat oven to adopt electric type is more appropriate. Because if the use of steam heating, make the door open for regular furnace temperature reached 200 ℃ more difficult. For consistent temperature in the furnace atmosphere, to minimize the temperature gradient, to set the appropriate hot-air circulating mechanism. By a motor driven fan, forced air heated in the furnace circular motion, so that the furnace temperature uniformity.


The volume of the furnace and the required heating power, and is based on the volume of production of the workpiece to choose. Clearly, the heating rate of the oven, along with the increase of electric power to accelerate. Because the various parts of different shapes and sizes, the difference of heat capacity is larger. Therefore, the different varieties of products, or changes in the number of products sent to the oven, in order to have a good time in the furnace to heat the workpiece, the furnace should be able to observe the situation plasticized workpiece. To this end, the door should be equipped with two thin layers of glass for viewing window. The size and position of the window, you should take into account the performance of the insulation, Youyi most convenient observation of each piece is a suitable furnace, the furnace should also be equipped with high-temperature tungsten lighting. Thus, the operator can always monitor the temperature of the workpiece in each process and plasticized outside the furnace, to determine the most appropriate time to remove the workpiece. Of course, if it is the same product type, and the same number every time you enter the oven, then after several exploration, will be able to identify its laws, implementation time process control, without having to constantly observing the workpiece. To minimize heat loss oven to accelerate the speed of the workpiece handling, oven floor should be installed on the rail, easy bake sports car, so the car out of the workpiece. For Hugh small size of the workpiece, or ovens are equipped with a device to allow rotation of the workpiece, or far infrared heating infrared heating technology can achieve good results, its energy-saving effect is remarkable. Commonly used oven temperature can reach 300 ℃, provided with hot air circulation system, the furnace temperature uniformity, it can conduct heat as epoxy, low-pressure polyethylene, polyester resins, chlorinated polyether powder spraying process test equipment.