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Conventional electrostatic charging(CORONA CHARGING) for powder coating

Conventional Electrostatic Charging (Corona Charging) by passing the powder through a high-voltage electrostatic field. High voltage (40-100 kV) concentrated at the nozzle of the spray gun causes ionizing of the air passing through the spray gun. Passage of the powder through this ionized air then allows free ions to adhere to a proportion of the powder particles whilst simultaneously applying a negative charge to them. Between the electrostatic spray gun and the object being coated, the following are present: ItRead More …

Powder particles are electrostatically charged using Corona or Tribostatic Charging

Today, practically all powder coatings are applied using an electrostatic spraying process. A common factor with all such processes is that the powder particles are electrically charged whilst the object requiring coating remains earthed. The resultant electrostatic attraction being adequate to allow the build-up of sufficient film of powder on the object, thus holding the dry powder in place until melting occurs with subsequent binding to the surface. Powder particles are electrostatically charged using one of the following techniques: ConventionalRead More …

Factors affecting the utilization of electrostatic spraying

The main parameters affecting the utilization of electrostatic spraying comprising: the type of nebulizer, the level of electrostatic spray parameters, the conductive,etc. Businesses use spray equipment decided to paint utilization factors, has a very different because of the different paint spraying equipment utilization. Nebulizer paint utilization of mainstream spraying equipment and childhood to greatly: Ordinary air gun, Electrostatic air spray gun Spinning cup Second, spraying environment for the utilization of paint, such as the presence or absence of and electrostaticRead More …

Six advantages of powder coating spraying in aluminum surface treatment

Aluminum surface treatment in general anodizing, electrophoretic coating and powder coating spraying three kinds of treatment, each of these methods have their own advantages, a considerable market share. Among them, the powder coating spraying there are the following significant advantages: 1.The process is relatively simple, mainly due to automatically improve the accuracy of the production process equipment, microcomputer control some of the major technical parameters can effectively reduce the difficulty of process operation, and auxiliary equipment is greatly reduced; 2.High yield,Read More …

Types of functional powder coatings

The powder coating is a new type of solvent-free 100% solid powder coating. Has a solvent-free, non-polluting, recyclable, environmentally friendly, saving energy and resources, and reduce labor intensity and the film mechanical strength. The coating form and the formation of the coating solids of up to 100%, because they do not use solvents, thereby reducing environmental pollution, conserve resources and recyclable characteristics. The functional powder coating is a special function, surface coating materials to provide for special purposes. It not only canRead More …

The significance of particle size distribution analsis for powder coating

laser particle size analyzer test results: Average particle size (median diameter), the boundary of particle size and particle size distribution of the dispersion. The average size of the sample is less than and greater than 50% of particles. The boundary particle size: closer to the common sense to the maximum and minimum particle size. However, the maximum and minimum particle size to describe the upper and lower limits of the sample particle size unscientific, it is generally the boundary particleRead More …

Big difference between bonded and non-bonded powders

Bonded and non-bonded are terms usually used when referring to metallic powder coating.  All metallics used to be non-bonded, which meant that a powder base coat was manufactured and then the metal flake was mixed with the powder to create a metallic. In bonded powders, the base coat is still manufactured separately, then the powder base coat and the metallic pigment are placed in a heated mixer and heated just enough to soften the powder. As the powder is mixedRead More …

D523-08 Standard text method for specular gloss

This standard is issued under the fixed designation D523; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval . A superscripl epsilon indicates an editorial change since the last revision or reapproval. This standard has been approved for use by agencies of the Department of Defense . 1.Scope This test method covers the measurement of theRead More …

Out-gas and adhesion problems in powder coat zinc casting

zinc casting can be powder coated. A cast part will have porosity that may cause blemishes in the coating at high temperature. Air that is trapped near the surface may expand and rupture the film during the cure process. There are several ways to mitigate the issue. You can preheat the part to drive off some of the trapped air that causes the problem. Heat the part to a temperature about 50°F greater than the cure temperature, cool it down, andRead More …

Introduction of Plasticizers in Coating Formulations

Plasticizers are used to control the film formation process of coatings based on physically drying film forming materials. Proper film formation is essential in order to meet demands on specific coating properties such as dry film appearance, substrate adhesion, elasticity, in combination with high level of hardness at the same time. Plasticizers function by reducing film formation temperature and elasticize the coating; plasticizers work by embedding themselves between the chains of polymers, spacing them apart (increasing the “free volume”), andRead More …