Ultrasonic Roll cleaning

The following guide notes have been supplied by:

Alphasonics (UCS) Ltd

18 Caddick Road

Knowsley Business Park South

Knowsley, Liverpool, L34 9HP, UK

Tel: 0151 547 3777

Web: www.alphasonics.co.uk

• Do not clean high-line aniloxes in low frequency systems. Alphasound systems operate at 54Khz and above and we would not recommend the use of frequencies lower than 54Khz.
• Do not clean any anilox rolls in a system that does not incorporate controlled roll rotation.
• Do not clean any aniloxes in a system that has generators which do not feature a frequency sweep. This feature, standard on all Alphasound systems prevents 'hot-spots' of ultrasonic activity which can cause damage to ceramic cells.
• Do not clean anilox rolls in a system that does not feature set timing periods. It is simply too easy for operators to put an anilox into any cleaning system and then get involved with something else. Automatic timed periods help prevent accidents in this respect.
• Make sure that the chemical solution in the tank is suitable for the purpose, do not use caustic solutions where aluminium is involved in the rolls construction. Different ink types require different chemicals in order to achieve the best results. Alphasonics range of chemicals covers most of the variables.
• Always rinse off the roll with fresh water after removal from the ultrasonic tank and dry immediately with some 'lint-free' paper waste.
• Always make sure that the solution in the tank is kept in optimum condition, preferably using a system that has an integral, automatic pump and filtration fitted. Any excessive build up of removed particles in suspension can cause vibro-etching, this is where particles are bombarded back onto the roll by the ultrasonic activity.
• Initial cleaning time for rolls that are being ultrasonically cleaned for the first time may be quite prolonged. For an Alphasound system we anticipate that badly contaminated rolls may require up to an hour to clean back properly. Thereafter, once a proper regime has been established we would expect rolls to clean in about 10-15 minutes.
• It should be remembered that Alphasound systems are not about cleaning rolls or cylinders at any cost, there are very much more powerful systems on the market. With variable power and targeted frequencies Alphasound is about providing the safest and the most efficient anilox roll cleaning systems available to the Flexo printer today. The well-being of the roll stock is always of paramount importance.
• Camouflage is really just an indication of contamination that has yet to be removed from the roll. As a roll is cleaning layers of old inks are coming off at different rates, this may occur more especially if there is no frequency sweep on the generators and as a consequence some areas of the reactive mass (solution) are more powerfully charged with ultrasound than others. Making sure that you have the correct value of, watts/litre (power) in the tank Making sure that the solution is fresh and correctly balanced, making sure you are using the correct chemical in solution in the first place all help to minimize camouflage and cause the roll to clean more readily.