Based on your previous experience focusing on LVDT sensor coaxiality testing and qualification in hot runner scenarios, coaxiality adjustment can be performed according to a standardized procedure:
Loosening and Releasing Allowance: Loosen the LVDT mounting screws, leaving approximately 1mm of radial fine-tuning clearance to avoid damaging the sensor structure by force.
Digital Calibration and Alignment: Attach the dial indicator to the rigid body of the hot runner needle valve, with the indicator head perpendicular to the outer circumference of the probe. Fine-tune the sensor radially, rotating it one revolution to control the radial runout within 0.02mm.
Dynamic Performance Verification and Confirmation: Manually push the probe through the preset full stroke, confirming no jamming throughout the stroke, stable motion resistance within the 5~10N range, and no abnormal force.
Tightening and Re-inspection for Curing: Tighten the mounting screws to the standard torque, and check again with the dial indicator to confirm no radial runout deviation. Power on and verify that the signal linearity error throughout the entire stroke is ≤0.5%. Final Hot-State Verification: The hot runner is heated to operating temperature and held for 2 hours. The needle valve is repeatedly driven back and forth to confirm no jamming and zero-point drift ≤0.01mm. Adjustment complete.
This process is fully adaptable to hot runner operating conditions, ensuring long-term stable coaxiality.
