Evaporation & Drying of solvent based paints with infrared
(primer, basecoat, topcoat and clear coat)
The evaporation of solvents from paints and the chemical crosslinking of paints can be accelerated or started by heat input by means of an infrared paint dryer. In paint drying and heat transfer in general, three fundamentally different mechanisms are used. (See also mechanisms of heat transfer)
In infrared dryers, the heat transfer takes place directly without a transmission medium. The infrared radiators are aligned for paint drying so that only the component and its paint layer heat up. This and the heating without intermediate medium result in a high thermal efficiency and higher power densities, which significantly lower heating and drying times can be achieved. The possibility of increasing the throughput due to shorter process times or saving production space, already when designing a system, are often decisive arguments for infrared drying.
Furthermore, due to the lower thermal mass of the radiator sources, infrared drying systems are significantly more responsive, which guarantees advantages in recipe changes and start-up processes.
Infrared paint dryer for solvent-based paints - unite EX protection with fast drying process-reliability
The evaporation of solvents or VOCs (abbreviation: volatile organic compound[s]) from the paint layer creates the danger of explosive atmospheres that can ignite on the hot surfaces of the infrared radiators.
The thermal processing technology division of IBT has developed a corresponding safety concept in accordance with the standard DIN EN 1539: 2016-02 ("Dryers and stoves in which flammable substances are released - Safety requirements") and designed an appropriate technology system for drying/varnishing plants. When designing the paint drying tunnel according to type A of the cited standard, the VOCs are diluted to a safety-technically permissible level below the lower explosion limit (LEL) of the respective VOCs. For this purpose, the maximum permissible mass flow of VOCs is coordinated with the plant operator and from this the required exhaust air volume flow is calculated.
In a growing number of drying lines, infrared and convection are combined to unite both advantages and minimize the effects of the disadvantages. The heating or intermediate drying is equipped with infrared heaters and thus ensures short heating times. This is followed by the drying section with convection. Here, a homogeneous temperature distribution is achieved and the paint dried at low operating costs.
Infrared systems for paint drying in industry for your application
Whether primer, basecoat, topcoat or clearcoat - IBT.InfraBioTech GmbH has extensive know-how in paint processing/paint drying using infrared systems.
We support you in the redesign, equipping or retrofitting of your drying systems with infrared technology. By retrofitting of existing paint plants, a significant cost savings compared to the purchase of a new plant could result.
You might also be interested in:
- Evaporation & Drying of water-based paint
- Gelation & Curing of powder coatings