After experiencing a repeating print defect, a customer called us in to assist in identifying the issue and resolve the problem.
The print mark was identified as a grease mark, which was appearing increasingly frequently and becoming more prominent on finished printed products. This was causing a significant increase in print rejects, downtime and an unhappy customer.
Although it seemed the cleaning of anilox rollers and surrounding components, such as the doctor blades, ink chambers and printing plates were being undertaken, the issue of grease marks was still persistent.
Once contacted our technician visited site promptly to investigate this issue to find the root cause of this greasing effect on the print.
On site, our technician discussed the issues being experienced and an understanding of the current care and maintenance procedures being undertaken, to gain an insight to any care problems.
Our technician then started to assess the various components of the flexographic process, which could be causing the greasing mark problem. Firstly, the condition of the doctor blades were assessed, to see if these were fitted correctly. The wrong, or incorrectly fitted doctor blades can cause several print issues. On inspection the doctor blades were found to be in good condition and correctly fitted.
We then checked the anilox rollers for signs of damage. No damage was found, but grease was found on the anilox rollers.
On founding the grease, we checked the Ink chambers. We often experience too much grease (or incorrect grease) is placed onto the ink chambers and when doctor blades are fitted the excess grease is pushed out. The excess grease is then transferred to the anilox roller and printing plate, which causes grease marks to appear on the print. This was not the case in this instance.
Our technician then began to review other elements of the maintenance around the anilox roller and ink chamber. On further discussion and investigation, a pipe was found to be split.
As part of the maintenance of the flexographic machine, various bearings need to be routinely greased. This is done by greasing selected parts of the press, through a grease point (or grease nipple), which leads to components such as bearings and other high friction areas.
It was noticed that the bearing was not being cleared of excess grease, after greasing. This does need to be done to avoid grease being transferred to the core elements of the print system.
In this instance, some of the grease travelling through the pipe, was leaking out onto the anilox roller, through the split pipe. This was causing the grease to be transferred to the printing plate and final print.
The pipe was replaced and the grease around the greasing aperture was thoroughly cleaned to ensure no residue grease could transfer to the anilox rollers and final print.
This was added to the maintenance procedures to check on a regular basis to avoid any similar print problems occurring.
The Added Value
On finding the damaged grease pipe, replacing this and cleaning around the greasing aperture, along with a complete clean using our cleaning solutions, we achieved print samples with no evidence of grease marks.
Returning a clean and undamaged system provided:
- Print without grease marks.
- Improved productivity
- Reduced rejects
- A happy customer
- Improved costs for the business
Regularly checking all core components and elements of your flexographic print process is imperative to delivering consistent high-quality print and productivity for your business.
Print Tech Solutions are please to provide the technical support to our customers, to support premium print.
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