Applicable Systems
Uhlmann Blister Machine
Symptoms
The Uhlmann blister machine displays alarm U007, indicating insufficient sealing pressure. The sealing station is not applying enough pressure to the web, causing weak or incomplete seals on the blister packs.
Possible Causes
- Sealing station pneumatic cylinder is leaking or the air pressure is below the setpoint
- Sealing pressure sensor has drifted, causing the controller to report incorrect pressure
- Seal plate is worn or has uneven surface, causing localized low-pressure areas in the seal
Troubleshooting Steps
- Step 1: Check the sealing cylinder air pressure and inspect for leaks
Air pressure is at the setpoint, typically 5-6 bar, and no air leaks are audible or detected with soap solution - Step 2: Calibrate or replace the sealing pressure sensor
Sensor reading matches the actual cylinder pressure within 5 percent across the operating range - Step 3: Inspect the seal plate surface for wear or unevenness with a straightedge
Seal plate surface is flat and even with no grooves or wear that would cause uneven sealing
How to Reset
To reset: 1) Repair the air cylinder or restore air pressure. 2) Replace the pressure sensor. 3) Resurface or replace the seal plate. 4) Press RESET. 5) Verify seal integrity with a leak test.
Source: Uhlmann Blister Machine Manual, Uhlmann Pac-Systeme GmbH
Category: Packaging