The application of UV curing has been growing in recent years and is present today in many industrial sectors.

UV radiation is electromagnetic radiation between x-rays and visible light. UV wavelengths range from 100 to 400 nanometer.

The UV wavelengths are divided in 4 groups: UV-A (315–400 nm), UV-B (280–315 nm), UV-C (200–280 nm) and Vacuum UV (100–200 nm).

 

The major advantages of this technology:

 

-No impact on physical, chemical properties of water and air.
-The curing process of the material ensures efficiency, quality and speed of production.
-Residue 100% solid
-It is possible to process the product immediately, with minimal change setups
-Low capital costs, power consumption and operational costs;
-Optimized functions for creating effects (example: high brightness, 3D, etc.)
-UV systems are compact and easy to operate; no need for special operational safety precautions.

Over the last century, UV light has played an increasingly key role in a variety of industrial applications:

-Printing: efficiency and high quality in printing processes (digital, offset, flexo, litho, screen and letterpress)  in various kinds of materials, MDF, PVC, glass, acrylic, adhesives, tarpaulins, aluminum or metal.

-UV light curing of materials: in the wood, plastic, glass, metal, and cement industry. Use of different photoinitiators which respond to different wavelengths:

• UV-V (400-450 nm): deep penetration for thick layers like varnishes (e.g. furniture)
• UV-A (370-400 nm): curing heavier inks/substrates.
• UV-A (315-370 nm): curing bulk substrate.
• UV-B/UV-C: used in conjugation with UV-A to cure the very surface of substrate.

-Decoration:  in the process of curing UV inks and coatings, resulting in product improvements, increased productivity (e.g. metal decoration in cans).

-Bonding: the printed circuit panels are exposed to UV light. Conformal coating material is applied to electronic circuitry to act as protection against moisture, dust, chemicals, and extreme temperatures.

-Air disinfection:  ultraviolet air purifiers are a new form of technology intended to substantially improve air quality and remove detrimental microbial particles that may be present in the air.

-Water disinfection: special UV lamps destroy microorganisms such as bacteria, viruses and parasites.

 

Experience shows that the useful life of a lamp is between 1000 and 3000 hours.

To maximize the life of the lamps is necessary verify  the system of ventilation, a non-polluting environment and the qualification of operators.

Some of the recommendations to help you to increase the life of your lamps:

 

-Avoid excessive starts: the lamps should be started at full power in order to reduce the start-up period. Excessive starts cause premature darkening of the ends, this will result in a drop in output as the darkening eventually migrates into the body of the lamp. To avoid these situations, whenever possible, gather all of the work to be done, start the lamp and perform all of the work that can be done during this time. 

 

-Check the lamps, reflectors and ventilation system: curing often fails due to poor lamp and system maintenance. Preventative maintenance is extremely important to minimize the problems in processes with UV technology. In order to increase the working life of lamps as well as the entire cure system it is advisable every 500 hours of operation, perform the following steps:

1-clean the lamp regularly to remove any dust, preventing devitrification problems. Lamps should always be handled using gloves and cleaned with isopropanol.

 

2-the reflectors have a function of improving efficiency of the system. Check if the reflectors are clean and free of distortion from the lamp’s radiated heat. Periodic cleaning and/or replacement of reflectors may be necessary to maintain maximum efficiency of both the lamp and equipment.

 

3-check the ventilation system: the accumulated dirt in the ventilation blocks causes the system to stop making the cooling necessary for proper functioning, causing overheating in the lamps and consequently a drop in voltage and power. The cleaning of the power supply system and air filters is essential.

 

4-Minimizing the risk of deformation: UV lamps generate much heat, so it is not uncommon deformations occur in the tubes, this phenomenon reduces the lifetime and efficiency. To minimize this risk, it is recommended to periodically run the lamps in 1/4 turn. Never directly touch the hot and even cold lamp, always use clean rubber gloves or cotton.

 

-Install Lamps with Care: avoid direct hand contact with the lamp tube. For handling use gloves or a paper towel. The use of an alcohol wipe is also recommended to assure clean surfaces. Important to ensure that the electrical connections are tight and not corroded.