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The causes of dust explosion and fire hazards during manufacturing powder coating
Powder coatings are of the fine organic materials, they can give rise to dust explosions. A dust explosion may break out when the following conditions happen at the same time. A ignition sources is present, including: (a) hot surfaces or flames;(b) electrical discharges or sparks;(c) electrostatic discharges. The concentration of dust in the air is between the Lower Explosive Limit (LEL) and Upper Explosion Limit (UEL). when a layer of deposited powder coating or a cloud comes into contact with anRead More …
More superioritis to liquid coating
For many reasons including environmental speaking,excellent performance ,high productivity and economics application,powder coatings have been used more and more since the 1970’s. It is clean,almost zero VOC. Additionally powder coatings provide easy clean up without harmful solvents and harmful waste. Over-sprayed powder can be recycled and reclaimed for greater economic savings than liquids paint.It reduce the cost of labor to coat products as much of application is automated.Powder coatings can not be modified at the clients site,thus eliminating inconsistency of products.Read More …
Particle Size Distribution
FINE PARTICLES Lower film builds Can blind cartridges and filters Migrate from part into exhaust Reduced fluidization properties Smoother films Absorb moisture more readily COARSER PARTICLES Higher film builds Increased Faraday penetration Increased fluidizaion properties
Powder Coatings Manufacturing
Weigh-up and Mixing ( raw material,such as resins,hardener,pigments,filler,etc) Extrusion Process Milling and Sieving
Phosphating conversion coatings
The recognized pre-treatment for steel substrates just prior to application of powder coatings 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 to locallyRead More …
Various Substrates for Powder Coating
Substrates Aluminium,steel,zinc alloys,copper and galvanized steel are common metals on which powder coatings are applied. In a number of cases where normal service conditions apply, satisfactory properties can be obtained on thoroughly cleaned metal. Aluminium For aluminium and its alloys,performance can be upgraded using a proprietary chromate conversion coating, even though the clean surfaces are easily coated and adhesion is excellent Steel For iron/steel surfaces maximum corrosion and salt spray resistance are given by a zinc phosphate conversion coating. Zinc alloys With allRead More …
Main aims in the pretreatment to metal surface before coating
The main aims in the preparation of a metal surface before powder coating may be defined as follows: The conditioning of the surface so as to render it suitable for the coating that is to be applied The complete removal of all foreign matte,e.g,scale,grease,cutting oil,soil,welding splatter,etc The pretreatment should impart uniformity throughout all treated workpiece surfaces,irrespective of the source of the metal or of the contaminants that might adhere. As with other methods of organic finishing attention to the pretreatment stage isRead More …
Loss of Mechanical and Chemical Properties
1.Poor Mechanical Properties and Chemical Resistance Cause: Too high or Too low curing temperature or time Solution: Confirm and check with powder coating supplier Cause:Oil,grease,extrusion oils,dust on the surface Solution:Optimize pretreatment Cause:Differing materials and material colors Solution:Insufficient pretreatment Cause:Incompatible pretreatment and powder coating Solution:Adjust pretreatment method,consult powder supplier 2.Greasy Surface(Haze like film on the surface which can be wiped off) Cause: Blooming effect-white film on the powder surface,which can be wiped off Solution:Change powder coating formula,increase curing temperature Cause: Insufficient airRead More …
D5 Creation