During the packaging production process, heat seal temperature out of control can easily lead to problems such as loose seals and material melting, which directly affects product yield and production efficiency. In view of the abnormal heat seal temperature of the packaging machine, the following calibration solutions are provided in combination with industry experience to help factories quickly restore equipment stability.
1. Temperature sensor calibration and replacement
Check the consistency of sensor resistance
Use a multimeter to detect the resistance of the temperature sensor (such as PT100 type). If the resistance deviates from the range of 100Ω±5% at 0℃, it needs to be replaced immediately .
Clean the sensor probe regularly to avoid oil or oxide layer interfering with signal transmission .
Optimize the sensor installation position
The sensor should be close to the surface of the heat seal knife (distance ≤3mm) to ensure real-time feedback of the real temperature .
Avoid direct contact between the sensor and the cooling fan to prevent airflow from interfering with the temperature measurement accuracy . 2. Reset the temperature control module parameters
Calibrate PID control parameters
Reset the temperature controller PID parameters (proportional band, integral time, differential time) to reduce temperature fluctuations to within ±5℃.
Use the step-by-step heating mode to avoid sensor misjudgment caused by power overload in the initial stage.
Check for line contact failure
Check whether the temperature control module terminals are loose, and focus on reinforcing the connection points between the relay and the solid-state switch.
Replace aging cables to reduce signal attenuation caused by increased line resistance.
3. Optimize the power matching of heating elements
Dynamically allocate the heating zone load
Multi-stage heat sealing knives need to balance the power of each heating zone to avoid local overheating or insufficient heating.
The power of a single zone is recommended to be ≤800W (industry general standard) to prevent current overload from burning the fuse.
Regularly check the status of the heating tube
Measure the resistance value of the heating tube. If the deviation is greater than 10%, replace the same specification element.
Clean the carbon on the surface of the heating tube to improve the heat conduction efficiency. 4. Coordinated adjustment of cooling system and pressure
Optimize cooling duct design
Clean cooling fan blades and vents every month to ensure cooling efficiency and reduce the risk of temperature control lag.
Auxiliary cooling devices (such as industrial air coolers) can be installed in high temperature environments.
Pressure-temperature linkage calibration
For every 0.5kg/cm² increase in sealing pressure, the heat sealing temperature needs to be reduced by 3-5℃ to balance heat conduction.
Check the parallelism of the bag pressing strip to avoid uneven pressure causing local temperature out of control.
5. Material adaptability verification and process matching
Establish a material heat sealing database
Preset temperature-pressure-speed parameter combinations according to the type of packaging material (such as PE, OPP, composite film).
It is recommended that the heat sealing temperature of biodegradable materials be 20-30℃ lower than that of conventional PE film.
Dynamic compensation of machine speed and temperature
When the packaging machine speed is increased to 40 bags/minute, the heat sealing temperature is increased by 5-8℃ to compensate for the shortened contact time. Keywords
Packing machine heat seal temperature out of control, packaging machine temperature sensor calibration, packaging machine PID temperature control system, packaging machine heating tube replacement.
