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Advantages of UV powder coating systems
UV powder coating formulations consist of:UV powder resin,Photoinitiator,Additives,Pigment / extenders. Curing of powder coatings with UV light can be described as “the best of two worlds”. This new method makes it possible to benefit from the advantages of high cure speed and low cure temperature as well as environmental friendliness. The main advantages of UV curable powder systems are: Low system costs Application of one layer Maximum powder use with overspray recycling Low cure temperature High cure speed Hardly anyRead More …
Thermosetting powder coating are much more widely used
Thermosetting powder coating are applied by the electrostatic spray process, heated to the necessary temperatureand cured and are primarily composed of relatively high molecular weightsolid resins and a crosslinker.The formulation of thermosetting powders contain the primary resins:Epoxy,Polyester,Acrylic. These primary resins are used with different crosslinkers to produce a variety of powder materials. Many crosslinkers, or cure agents, are used in powder coatings, including amines, anhydrides, melamines, and blocked or non-blocked isocyanates.Some materials also use more than one resin in hybridRead More …
Urethane cured polyester powder coating
Urethane cured polyester powder coating has excellent resistance to outdoor environments, toughness and very good appearance characteristics at 1 to 2 mil film thickness.A smooth, thin film that resists weathering and physical abuse makes the urethane polyesters a popular finish for high quality products. It is common to block the crosslinker in urethane polyesters with ecaprolactam.To begin the cross linking process, the material must reach a temperature above the blocking agent threshold. With e-caprolactam, unblocking occurs at approximately 360 °F (182Read More …
Installation of spray booths
The powder supply and coating powder feedlines should be interlocked with the air extraction system,so that ,in the event of failure of the ventilatioon system,the coating powder and powder supplies are cut off.Airflow monitor switches are the preferred method of detecting failure of the ventilation system.Such equipment will also be sensitive to blocked filters and broken or loose fan blades. A fire detecting device,interlocked to shut off powder and coating powder supplies and ventilation may be installed in the boothRead More …
Location of stoving ovens
The stoving oven should be situated at least 1m from the powder spraying installation and arranged so that powder cannot accumulate or be spilled near to the oven,its air intakes,hot surfaces or any electrical apparatus.Air movement within the oven should not be so high as to blow off powder from the work piece before fusion . The clean air change requirement of the oven should be known and visibly marked on the oven. For conveyor ovens and especially those usingRead More …
How silver ions works in antimicrobial powder coating
Antimicrobial powder coating is widely used in many industries nowadays,such as Building Products,Food Service,Healthcare,Home Products and Packaging.This kind powders contain a silver ions,which act as antagonist over many bacterium. With the presence of moisture, silver ions are gradually released to function as an anti-microbial material. Silver ions charged with plus are drawn toward the microbe’s cell wall charged with minus to disturb the electrical balance. The cell wall of the microbe thus bursts and is extinguished. As silver ions enterRead More …
Requirements for powder coating over hot dip galvanizing
The following specification is recommended: Use zinc phosphate pretreatment if highest adhesion is required. Surface must be perfectly clean. Zinc phosphate has no detergent action and will not remove oil or soil. Use iron phosphate if standard performance is required. Iron phosphate has a slight detergent action and will remove small amounts of surface contamination. Best used for pre-galvanized products. Pre-heat work prior to powder application. Use ‘degassing’ grade polyester powder coating only . Check for correct curing by solventRead More …
The solutions for the problems of powder coating over hot dip galvanizing
1. Incomplete curing: Polyester powder coating powder is thermosetting resins that cross-link to their final organic form by being maintained at a temperature (typically 180 o C), for about 10 minutes. Curing ovens are designed to provide this time at temperature combination. With hot dip galvanized items, with their heavier section thickness, it is necessary to ensure that sufficient stoving time is allowed to meet the curing specifications. Pre-heating of the heavier work will assist in accelerating the curing processRead More …
The problems with powder coating application over galvanized surface
Polyester powder coating over hot dip galvanized steel provides a high grade architectural finish to steel items with excellent atmospheric weathering characteristics.The powder coated product ensures maximum durability for steel components, which will generally provide 50 year+ rust free life spans in most architectural applications. Even so there are still some problems during this application. Hot dip galvanized surfaces have been acknowledged as difficult to powder coating since the technology was first developed in the 1960’s. Industrial Galvanizers commenced research inRead More …
How to prevent powder dust explosion
An explosion can be prevented if both or either of the conditions Explosive Limit and Source of ignition are avoided. Powder coating system should be designed to prevent both conditions occurring ,but due to the difficulty of totally eliminating sources of ignition,more reliance should be placed on the prevention of explosive concentrations of powder. This can be achieved by ensuring that the powder in air concentration is kept below 50% of the Lower Explosive Limit(LEL). Determined LELs on the range ofRead More …