Powder Coating

Delta Coat Powder Coating

Powder coating is a method of applying a protective and decorative finish to metal surfaces, including steel and aluminum. The process involves applying a dry powder made of finely ground particles of pigment and resin onto a pre-treated metal surface. The coated metal is then heated, causing the powder to melt and fuse into a smooth, durable finish.

Every fabricated metal part entrusted to Delta Coat undergoes a meticulous preparation process. Initially, we subject it to chemical stripping, degreasing, or sandblasting to ensure that the surface is impeccably clean and ready for coating. Following this, a uniform application of powder coating takes place, and the part is subsequently baked. The outcome is a robust, sleek, paint-like finish, as exemplified in the accompanying picture. 

Powder coating procedure:

Cleaning

The materials are hung in frames and are dipped in tanks in the following order.

a) Acid Etching & Degreasing

The substrate material is quenched in the degreasing chemical tank for five minutes so that it removes any presence of oil, grease, or any other dissolvable semi solid contamination on the material substrate. The same will make the surface rough so that the powder gets good adhesion on the material substrate.

b) Rinsing

Removes reaction sludge from the material substrate.

c1) Chromium-Free Conversion Coating (Activation):(For Aluminium Materials)

This process ensures the coating adheres chemically to the substrate. The substrate material is quenched in the chemical tank for 45 sec to max one minute.

c2) Iron Phosphate Conversion & Cleaning: (For HDG Materials)

Adding an iron phosphate stage to your pretreatment can dramatically improve the quality and longevity of your powder coating. Iron phosphate provides increased adhesion. Iron phosphate pretreatment causes a small amount of surface material to be deposited on the parts being treated. This material is slightly textured so the powder can grip it. If the parts are occasionally bumped during their use, this improved adhesion is especially helpful because it keeps the coating intact.

d) Rinsing:(For HDG materials only)

Removes reaction sludge from the material substrate.

Note: In case if the material cannot be cleaned by chemical treatment due to some reason, alternative methods like grinding, sanding, and blasting may be adopted depending on the type and condition of the material.

Pre-Heating

The materials are hung in the crane and are made to run in a pre-heat oven to dry of any liquids / oil / grease before powder coating.

Powder Coating

The materials then pass through the powder coating booth where they are coated with the desired color and coating thickness.

Curing

The materials are cured in the curing oven at 200 degrees centigrade plus and made to stay in the oven for minimum of 10 minutes.

Quality Check

The materials are taken out from the conveyor and checked for quality using a cross hatch cutter according to the Standards of ASTM – D 3359-08. The thickness of the coating varies depending on the base material and the customer’s requirement as well. Normally acceptable thickness for coating is 60-80 Microns, +/- 5 Microns. The thickness of the coating is measured by using Elcometer.

Packing

If the material is found acceptable, it is bundled and packed using plastic film & PP strap, respectively.