Milacron Elektron 400/500/600 Full Electric Injection Molding Machine On site Maintenance and Troubleshooting Complete Guide

Chapter 3 Maintenance and Troubleshooting of Locking Mechanism

3.1 Structural Features

Elektron adopts a double toggle locking mechanism, which is driven by a high-precision servo motor to open and close the mold using ball screws and synchronous belts. The mobile template is equipped with high-precision linear guides, which can maintain the parallelism of the template even under heavy load and high-speed operation. The locking force is automatically set through software (the tonnage is inputted on the screen, and the system automatically adjusts the clamping position).

3.2 Common faults and their solutions

Fault A: The actual locking force is much lower than the set value, causing the product to flash

Possible reasons:

The thickness of the mold changes or the parallelism of the template exceeds the tolerance.

The wear of ball screws leads to a decrease in transmission efficiency.

The synchronous belt is not tensioned enough.

Troubleshooting steps:

Use the 'Lock Force Calibration' function of Endura Touch to automatically execute the semi closed mold calibration program.

Use a dial gauge to check if the elongation of the four pull rods is consistent (a difference of>0.1mm indicates template tilt).

Check the synchronous belt: Open the rear cover, press the center of the synchronous belt, and the deflection should be 10-15mm (apply a force of about 50N using a spring scale). If it is too loose, adjust the tensioner.

Listen for any abnormal noise from the ball screw - if so, disassemble and inspect the screw raceway and nut.

Fault B: The stop position of the mold opening and closing is unstable (with a difference of>0.5mm each time)

Reason: Interference from servo motor encoder or loss of pulse counting; The mechanical clearance is too large.

handle:

Check if the encoder cable is routed separately from the power line (with a minimum spacing of 200mm).

Execute the 'zero reference point recalibration' procedure: manually move the template to the mechanical hard limit and reset the origin point according to the on-screen instructions.

If it still drifts, measure the clearance between the sliding guide rails: move the template to the middle position, use a pry bar to pry the end face of the template, and if the displacement sensor reading exceeds 0.2mm, replace the guide rail slider.

Fault C: Frequent false triggering of mold protection (low voltage and low speed section alarm)

Reason: The mold protection pressure threshold is set too low; Abnormal resistance caused by foreign objects or poor lubrication in the guide rail.

Adjustment:

On the "mold clamping settings" page, enter "two-stage mold protection" and increase the low-pressure protection pressure limit appropriately (usually 5-8% of the locking force).

Enable the 'try again function' - if the protection is triggered for the first time, the system will automatically reverse and attempt to close the mold again to avoid unnecessary downtime.

3.3 Maintenance of Automatic Lubrication System

The Elektron locking mechanism adopts an automatic central grease system, which automatically injects grease every 1000 cycles or every 2 hours. Maintenance points:

Check the oil level of the grease tank monthly (using Kl ü ber Isoflex NBU 15 or equivalent).

Clean the distribution block filter every 6 months.

If there is no grease discharge from a certain lubrication point (such as the moving template guide rail), it may be due to a blocked distribution valve, which needs to be cleared with a fine wire and manually greased.

Chapter 4 Precise Adjustment and Fault Diagnosis of Injection Unit

4.1 Composition of Injection System

The injection shaft is driven by a servo motor to push the ball screw forward; The plasticizing shaft is driven by an independent motor to rotate the screw. Both can operate in parallel in the same loop, reducing cycle time. The injection pressure is directly measured by a high-precision load cell at the rear of the screw, which measures the melt pressure and feeds it back to the closed-loop control system.

4.2 Common Injection Malfunctions

Problem 1: The actual injection pressure deviates significantly from the set value (exceeding ± 5%)

Reason: Zero drift of load sensor or poor contact of signal line.

handle:

Execute 'Zero Pressure Calibration' in the 'Injection Calibration' menu (separate the nozzle from the mold to ensure no back pressure).

Check if the load sensor cable plug is loose (usually located at the rear of the injection unit). If the calibration is still inaccurate, the sensor (usually HBM or Kistler model) needs to be replaced.

Attention: After replacing the sensor, it must be recalibrated and old parameters cannot be directly used.

Problem 2: Unstable injection speed, especially during short shots

Possible reasons:

Synchronous belt wear or insufficient tension (injection shaft drive belt).

Wear of the screw check ring (causing melt reflux).

The servo drive parameters (speed loop PID) need to be optimized.

Troubleshooting process:

Perform a 'semi-automatic injection' test and observe the injection speed curve. If there are periodic fluctuations on the curve, it may be damage to the screw raceway.