Balance Your Dryers – Minimize Dirty Print

One of the most common print defects that customers report to our Technical Solutions Group is dirty print. While this print defect lends itself to a host of root causes, interestingly it is one of the most basic operations of the press optimization. When BC dryers are not balanced, air can blow on the anilox or plate surface which can quickly lead to dirty print issues and ink build up. Below is a quick refresher on how to properly set the balance of BC dryers on a wide-web CI press.

1. Determine if there is a screen system, if screens exist please verify that the screens are clean and free of foreign objects. It makes no sense to attempt to balance dryers when there are objects or debris present. When these items exist, the conditions are perfect for a continuous break drown of airflow, making balance nearly impossible long term.
2. Assure all hoses are clean, free of blockage, and open for proper airflow and that all of the connections are properly installed and secure.
3. Determine open and closed direction of flapper valves, or what some refer to as dampers. Assure these valves are clearly identified and marked for direction of flow, open/closed.
4. Start with deck 1. Fully open exhaust, while holding smoke stick along dryer at CI drum, have helper slowly open the in feed valve. When the smoke starts to push out have the helper stop. Then slowly close in feed valve until smoke begins to be sucked back into dryer. Note: it is important that you find the exact point where the smoke is just starting to be pulled into the dryer.
5. Once you have determined the correct position of the in feed valve, mark and lock this valve in place. This will assure that the dryers will stay balanced.
6. After deck 1 is complete start over at step 3 for remainder of decks to be balanced.

We have formed our Technical Solutions Group to encompass our full range of expertise in all critical areas of the flexo process. This team is made up of industry professionals dedicated to being up to date on new technologies, armed with the last in diagnostic tools, and experienced in problem solving that can achieve sustainable results.