Price on request
Price on request
Price on request
Price on request
Price on request
Price on request
Price on request
Price on request
Price on request
Price on request
Price on request
Price on request
Price on request
Price on request
Powder coating – how it works
Powder coating is a coating process that is becoming increasingly important in the industrial sector, mainly due to its economic potential. This process can be carried out both automatically with powder coating systems and manually with a manual powder coating system. The principle is simple: the plastic powder is electrostatically sprayed on and adheres to the workpiece.
When the object is then heated to approx. 200 °C, the plastic powder flows and cross-links to form a durable, decorative surface coating. Examples of applications include radiators, household appliances, machine casings and table legs.
Powder coatings consist of binders, colour pigments and fillers. The adhesive contains a synthetic resin component (such as acrylate, epoxy, polyester or polyurethane resin) and a hardener, which only react with the workpiece in the oven. This creates an elastic coating film in the adhesive system.
A less common type of coating is fluidised bed sintering. In this process, the heated workpiece is immersed in a mass of plastic powder, which melts together with the warm workpiece. This process mainly uses thermoplastic powder and enables greater layer thicknesses, e.g. for garden furniture and wire baskets for washing machines.
The advantages of powder coating
- High durability: powder-coated surfaces are highly resistant to chemicals and mechanical wear.
- Covering power: small irregularities in the substrate are well masked by the high layer thickness.
- Environmentally friendly: no expensive, toxic, flammable or explosive solvents; easy disposal and no wastewater problems.
- Cost savings: powder coatings are more cost-effective and can be processed with almost no loss.
- Efficiency: Coating thicknesses of 40 to 120 µm are possible in a single operation.
- Self-limiting: the electrostatic process is self-limiting, excess powder is repelled.
- Quality: optimal quality properties are already achieved in the single-layer system.
- Less shrinkage: Less shrinkage of the powder coating layer during baking.
- No solvent residues: No solvent residues remain after baking.
- Energy efficiency: No expensive preheating of the sucked air in the spray booth is necessary.
- Safety: No separate, explosion-proof and heated paint storage rooms are necessary.
- No segregation: pigments do not float to the surface during film formation.
- Priming: No priming necessary.
- UV protection: UV protection even without a clear varnish.
- Automation: The process can easily be automated.
We will be happy to advise you if you are planning a new powder coating plant. The Gema team is at your disposal to answer any questions you may have about powder coating.
About Gema Switzerland GmbH
Gema Switzerland GmbH is a leading global provider in the field of electrostatic powder coating. More than 3,500 automatic systems with booths and over 250,000 powder guns from Gema are in use worldwide. The Swiss company offers solutions that meet the requirements and needs of customers from various industries worldwide, ranging from simple manual coating to fully automatic powder coating. Since 2012, Gema has been part of the international Graco Group, a leading manufacturer of fluid handling systems and components.
