Applicable Systems
Haitian Injection Molding Machine
Symptoms
The Haitian injection molding machine displays alarm HT003, indicating screw position deviation. The screw position during injection or holding has deviated from the setpoint beyond the allowed tolerance, indicating a mechanical or control issue.
Possible Causes
- Screw is slipping on the thrust bearing, causing the actual position to lag behind the commanded position
- Linear position transducer has drifted or the mounting is loose, causing inaccurate position feedback
- Melt is leaking past the check ring, causing the screw to move forward without injecting material into the mold
Troubleshooting Steps
- Step 1: Check the thrust bearing and screw drive coupling for wear or slipping
Bearing and coupling are tight with no play, and the screw moves precisely with the drive command - Step 2: Calibrate the linear position transducer against a reference measurement
Transducer reading matches the actual screw position within 0.5mm across the full stroke - Step 3: Inspect the check ring and non-return valve for leakage during injection
Check ring seals tightly during injection with no backflow or screw creep detected
How to Reset
To reset: 1) Replace the thrust bearing or coupling. 2) Replace or recalibrate the position transducer. 3) Replace the check ring. 4) Press RESET. 5) Verify screw position accuracy during a test shot.
Source: Haitian Injection Molding Machine Manual, Haitian International Holdings
Category: Injection Molding