How to Maintain Your Hot Plate Welding Machine for Long-Term Performance - Chinese leading plastic welding machine manufacturer

Table of Contents

Common Hot Plate Welding Phenomena, Causes, and Solutions

Phenomenon	Reason	Solution
Excessive welding	The energy input is too much	– Reduce the pressure- Reduce the melt time- Reduce the upper mold lowering speed
Inadequate welding	The energy input is too little	– Increase the pressure- Extend the melt time- Use a hot plate welding machine with higher power
Welding uneven	Product distortion	– Check if product dimensions are consistent- Check if distortion is caused by operating conditions
	The product’s contact surface is uneven	– Adjust the trim screw- Adjust the limit screw- Check the product’s shape and size
Hot plate stained	Excessive temperature	– Plate the hot mold surface with Teflon or use Teflon cloth at the welding surface- Reduce the set temperature
Abnormal sound during operation	Basic standard is loose	– Reset and adjust the base
	Screws or nuts are loose	– Reset and tighten all screws and nuts
	Lower door is not closed	– Ensure all doors are locked
	Machine feet are uneven	– After turning off the hot plate welding machine, level the feet and lock them

Electric Fault Troubleshooting Table

Part	Phenomenon	Reason	Solution
Pneumatic	Component and remove the system was not any action	The magnetic valve was not started	First check all magnetic valves, adjust air pressure per operation guide; if no abnormality, replace the magnetic valve.
Pneumatic	Component and remove the system was not any action	Interference with other parts	Click the reset button to reset all components.
Pneumatic	Component and remove the system was not any action	Pneumatic system has leakage	Check all air circuits and connections for leakage.
Pneumatic	Component and remove the system was not any action	Air pressure is too low	Adjust the pressure valve and use a pressure gauge to ensure normal air pressure.
Pneumatic	Component and remove the system was not any action	Magnetic valve or electrical connection fault	Manually test each valve. If no action, replace the magnetic valve.
Manual Mode	Hot plate cylinder not working	Select switch is not in manual mode	Check if the select switch is set to manual.
Manual Mode	Hot plate cylinder not working	Air tube or valve is damaged	Replace damaged parts.
Manual Mode	Hot plate cylinder not working	Upper/lower fixture not in reset state	Check reset magnetic switch status; adjust if not lit.
Manual Mode	Hot plate cylinder not working	No output from PLC	Check communication between touch screen and controller; replace controller if needed.
Manual Mode	Hot plate cylinder not working	Emergency stop is abnormal	Check emergency stop is released and circuit connection is normal.
Manual Mode	Upper/lower cool mould not working	Select switch is not in manual mode	Check if the select switch is set to manual.
Manual Mode	Upper/lower cool mould not working	Mechanical jam	Remove any jammed objects.
Manual Mode	Upper/lower cool mould not working	Hot plate slider not in position	Move hot plate slider to reset or weld position.
Manual Mode	Upper/lower cool mould not working	No output from PLC	Check communication between touch screen and controller; replace controller if needed.
Manual Mode	Upper/lower cool mould not working	Emergency stop is abnormal	Check emergency stop is released and circuit connection is normal.
Manual Mode	Upper/lower fixture not working	Select switch is not in manual mode	Check if the select switch is set to manual.
Manual Mode	Upper/lower fixture not working	Mechanical jam	Remove any jammed objects.
Manual Mode	Upper/lower fixture not working	Air tube or valve is damaged	Replace damaged parts.
Manual Mode	Upper/lower fixture not working	Fixture button failure	Check if fixture button is damaged and circuit connection is normal.
Manual Mode	Upper/lower fixture not working	No output from PLC	Check communication between touch screen and controller; replace controller if needed.
Auto Mode	hot plate welding Machine not running	Select switch is not in auto mode	Check if the select switch is set to auto.
Auto Mode	Position not reached	Upper/lower/slider magnetic switches not reset	Ensure all magnetic switches are in reset state.
Auto Mode	Safety curtain or emergency stop abnormal	Blocked light curtain or open emergency stop	Remove obstruction, check emergency stop and wiring.
Auto Mode	Start button not working	Start button damaged or wiring abnormal	Check and replace the start button and wiring if needed.
Auto Mode	PLC has no output	PLC controller fault	Replace the controller.
Auto Mode	Fixture does not activate	Fixture solenoid valve not energized	Ensure valve is powered; if not, hot plate welding machine won’t start.
Auto Mode	Slider does not move forward after start	Air pressure is too low	Adjust pressure valve to reach specified level.
Auto Mode	Slider cannot reach forward position	Magnetic switch not triggered	Check if slider reaches position; adjust magnetic switch if not lit.
Auto Mode	No timer after reaching hot position	Hot position magnetic switch not lit	Confirm upper/lower mold in position; adjust hot magnetic switch if needed.
Auto Mode	No solidification timing	Curing magnetic switch not lit	Confirm molds are closed; adjust curing switch position to activate.
Auto Mode	Fixture cylinder does not release after welding	Upper sucker still has suction	Replace small sucker or reduce upper sucker air pressure.
Auto Mode	Lower fixture cylinder not released	PLC program error	Modify PLC program; alternatively, press reset button to release cylinder.

Other Faults and Alarm Troubleshooting Table

Fault Phenomenon	Fault Cause	Solution Method
Other fault and solution	Proximity switch did not respond	Check each proximity switch and adjust correctly. If still not lit after adjustment, replace the magnetic switch.
Other fault and solution	Set position is wrong	Calculate the correct position and properly adjust the magnetic switch.
Other fault and solution	Pressure supply problem	Check if the air source has pressure, and adjust the pressure valve to the specified level.
Other fault and solution	Electrical part malfunction	Replace damaged or faulty electrical components.
Cannot start	No power or blown fuse	Check whether there is 220V at the circuit breaker and whether the fuse is blown.
Touch screen does not respond when clicked	Communication or controller not working	Check communication between touch screen and controller. If communication fails, check cable; if controller is stopped, ensure voltage is correct and set to “RUN”.