Coating Painting Process and Paint Curing Methods

 Paint/coating application in the coil coating process follows the pretreatment process and the coating process consists of two stages, namely primer application and topcoat application. The painting process is also divided into various kinds, and the paint curing methods are different for each of them. LITONG, as a professional coating line supplier, we are happy to introduce you the knowledge about it.

 

Coil coating line

1, with a single coater and oven. These lines serve a market primarily oriented towards consumer products, consisting of cold rolled steel (CRS), tinned mill black plate (TMBP) and/or tin-free steel (TFS). Although product availability is limited, these lines offer significant cost advantages over lines running two or more coaters and ovens on a single line.
2, lines with two or more coaters are called tandem lines, and they are capable of applying primer and topcoat in a single pass. These lines primarily serve the construction and appliance markets.

 

The TZ1600-35 coating line (split type) is suitable for some coating plants. 2-side 2-coating coating products are suitable for most ACP materials, roofing and ceiling materials.LITONG coating lines are high quality coating lines that perform well in a variety of paint applications. Separate structure for flexible production, pre-treatment and coating processes are separated and do not interfere with each other, making production easier to plan or schedule. Operational failures and equipment problems have less impact.
Applications: For coating of ACP (Aluminum Composite Panel) aluminum coils, roofing, cladding, ceilings, roller shutters, etc.
Advantages: wide range of use, short lines, smaller plant area required, less impact of operational failures and equipment problems.

 

Coater Design

A variety of coater designs are available depending on the configuration of the coil line, the type of coating used, and the type of metal being coated.

Reverse roller coating process.

The coating is circulated in the paint tray, the rotating pick-up roller is partially immersed in the coating and rotates counterclockwise, then the coating is transferred to the clockwise rotating coating roller.
This special configuration is used for most products and is capable of achieving a coating thickness of 1.0 mil (0.001") on most coatings.

Direct coating process.

Thinner coatings and printing use a similar configuration, but with the rolls oriented in opposite directions, so the coating roll has the same surface orientation as the web and the pick-up roll has the same surface orientation as the coating roll. Direct coating requires additional equipment due to the dangerous pinch point between the two rolls.

 

Methods of curing paint

1, The curing part of a coil coating line has as many variations and advances as all other parts combined. The most common drying and curing technique is convection or flotation curing using gas ovens.
2, There are two types of electrical curing techniques used for coil coating, induction and infrared (or near infrared) curing.
Induction curing works by heating a metal substrate by passing the metal strip through a magnetic field that induces an electric current in the strip and creates a heating effect through electrical resistance.
Painters using water-based coatings are able to utilize electric and gas infrared ovens because they reduce maintenance costs. ,
3, Radiation cured coatings are widely used in many different industries, but have not yet found significant use in coil coatings.

LITONG is the successful practice of breaking through the traditional processing industry and moving towards a high-tech professional manufacturing industry. We specialize in designing and manufacturing environmental protection production lines, aluminum-plastic composite panel composite lines, aluminum color coating lines, steel color coating lines, continuous aluminum anodizing color coating lines. If you would like to get a quote, please send us a message today.