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Dryers based on air insufflation (water-based painting) > < Spray guns and their use

Polo Mk4

Paint dryers by irradiation
Paint dryers by irradiation
These are used mainly for small paint repairs. They require little space and have low operational costs. They are called fixed dryers. Presently dryers via infrared rays are predominantly used. Great improvements are obtained in the paint drying process with them. The infrared rays cross the air and the enamel layer, without direct heating. The steel plate is heated and transmits the heat to the enamel layer.
  Note
In order to dry the paint on high-resistance plates, by using the infrared ray dryers, these may be taken to full power only slowly. Otherwise excessively quick heating of the plates causes dilation which later, after cooling down, causes undulations in the bonding or spot-welding area.
   
Advantages of the infrared technique:
t  The drying process occurs from the inside to the outside
t  The flash-off time is shorter than with hot-air systems
t  Quicker drying reduces the risk of dust deposition
t  Efficient use of energy
The IV dryers are divided into three groups:
t  Short-wave dryer
t  Medium-wave dryer
t  Long-wave dryer
The most adequate ones for the drying process are the short-wave and medium-wave dryers.
The short-wave appliances generate the irradiation through quartz tubes. They irradiate in the field of vision and emit a red or orange light. It reaches the working temperature in a few seconds. These appliances have an intensive irradiation with a short flash-off time.
The medium-wave dryers generate the rays by means of ceramic tubes. They irradiate in the non-visual field. They only reach the working temperature after a few minutes. Hence the flash-off times are longer than those with short-wave dryers.
In principle, all materials can be dried with the infrared drying technique.
The flash-off time of the infrared dryers, at a distance of 80 cm, comprises:
t  Polyester scraper = 2 minutes
t  Painting scraper = 2 - 7 minutes
t  Soluble stuffing base in water = 7 - 9 minutes
t  Base = 3 - 8 minutes
t  Covering painting = 7 - 10 minutes
  R00-20243

Dryers based on air insufflation (water-based painting) > < Spray guns and their use