Compressed air filtration and drying system for surface coating

By OEM Update Editorial August 10, 2018 3:04 pm IST

The presence of oil, moisture and dust particles in filtered dry air as per ISO recommendation results in increase machine up time, lower rejection and better product quality. The common contaminants in compressed air dust, moisture and oil.

Dust
Atmospheric dust content varies from 0.01µ to 100 µ in size. 90 per cent of these impurities are from 0.1 to 10 µ; majority of which are not removed by compressor suction filter.

Moisture
Form of moisture:
• Liquid
• Aerosol
• Vapour

Oil
Form of moisture:
• Liquid
• Aerosol
• Vapour

Adsorption dryers
There are several different types of regenerative dryers but they all confirm to the same basic concept. A regenerative dryer consists of two pressure vessels or towers filled with the desiccant. The desiccant in one bed is on stream, drying the air, while the desiccant in the other tower is being regenerated. The two towers are interlinked with switching valves so that the desiccant in the drying tower is saturated and the valves switch the flow into the tower that has just been regenerated. This switching operation is automatic, giving continuous drying.

With adsorption dryer, very low dew point upto (-)400C or (-)600C can be easily achieved. In special application, where very dry air is required, only an adsorption dryer will do.

Benefits of using dryer
• No blister formation on coated surface
• No stains of oil on coated surface
• Even paint finished surface
• Almost nil rejections
• Less powder consumption
• Increases life of powder gun
• Less maintenance + spares requirement of coating equipments
• Negligible wastage of costly man-hour caused by rejection & maintenance
• Substantial decrease in cost of production hence higher profit margin.

For more details, visit
www.drytechengineers.com