White Ink Pressing Issues in YDM UV Flatbed Printers

Title: Professional Guide to Resolving Coating and White Ink Pressing Issues in YDM UV Flatbed Printers

YDM vision-positioning UV flatbed printers are highly regarded in the printing industry for their high precision and stability. However, users may occasionally encounter issues where coating or white ink fails to press/purge, affecting printing efficiency and potentially causing material waste. This article systematically analyzes the common causes of this problem and provides solutions to help quickly restore normal equipment operation.

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I. Common Problems and Solutions

1. Filter and Ink Line Clogging

Possible Cause: Clogged butterfly filter or obstructed ink line from the filter to the secondary ink tank.

Solution: Replace the butterfly filter and thoroughly clean the ink lines to ensure smooth ink flow.

2. Ink Pump Malfunction

Possible Cause: Incorrect wiring or pump failure.

Solution: Check the wiring connections. If the wiring is correct but the pump still doesn't work, replace the ink pump.

3. Printhead Clogging

Possible Cause: Ink curing or residual cleaning fluid causing nozzle blockages.

Solution: Flush the printhead with specialized restoration fluid or cleaning fluid, ensuring complete removal of any residue.

4. Secondary Ink Tank Issues

Switch Off: Ensure the secondary ink tank switch is turned on.

Floater Damaged: Replace the floater if it is malfunctioning.

Insufficient Ink: Check if the primary ink tank is low on ink and refill promptly.

5. Air Pressure Abnormalities

Positive Pressure Abnormal: Check if the positive pressure value is within the normal range.

Insufficient Positive Pressure in Negative Pressure Tank: Appropriately increase the positive pressure value in the negative pressure tank.

6. Kinked or Mispositioned Ink Lines

Solution: Check if ink lines are pinched or kinked, readjust and secure their position.

7. Button and Wiring Issues

Purging Button Damaged: Check the wiring for breaks or damage; replace the button if necessary.

Incorrect Wiring: Ensure the purging button is wired correctly. Check the color sequence during ink charging by purging.

8. Environmental and Operational Factors

UV Light Reflection Curing: When printing on reflective materials like glass, UV light might reflect onto the printhead, curing the ink. Use restoration fluid or red ink solution to wipe the printhead.

Residual Cleaning Fluid: After cleaning the printhead, it must be thoroughly rinsed to avoid blockages caused by leftover fluid.

Nozzle Crystallization: Avoid direct light exposure on the printhead and perform regular cleaning maintenance.

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II. Prevention and Maintenance Recommendations

To prevent issues with coating or white ink failing to purge, users are advised to perform the following maintenance regularly:

Regular Filter Replacement: Check and replace the butterfly filter periodically based on usage frequency.

Maintain Clear Ink Paths: Ensure ink lines are free of kinks and blockages after each cleaning.

Check the Air Pressure System: Ensure positive and negative pressure values remain stable within the equipment's required range.

Standardize Operating Procedures: Charge ink color by color, avoiding wrong connections or ink mixing.

Environmental Control: Avoid exposing the equipment to strong light or high temperatures to reduce the risk of printhead curing.