当前位置: HOME>SERVICE>Knowledge

Common fault and troubleshooting of straight cutting machine


Phenomenon Troubleshooting
No speed display Fault of 5V power plate (replace)
Big trolley moves but no transversal movement or
transversal moves but big trolley does not move
Fault of relay (replace) limit fault
No action for both big or small trolleys Exciting adjustment power plate is broken (check fuse) replace
no pressure for cutting oxygen in cutting torch Block of back fire arrester (replace)
broken electro-magnetic valve (replace)




Common fault and troubleshooting of assembling machine


Phenomenon Troubleshooting
Spot welding cannot stop Broken time relay (replace) 
fault of contactor (replace)
Welding device should be on no-arc position (adjust switch)
Motor fails to operate. fault of motor (replace)
inverter alarms (adjust according to alarm No. on manual)
Danfoss, Emerson and Taian inverter
Not in the center Adjust eccentric rate of flange plate supporting 
wheels and web plate supporting 
wheels then lock the locking screw.
no action when the 
welding torch in the 
working position
Check stuck pipe of mechanical part. (adjust)
Check the pressure of gas supply. (adjust)
Check the electromagnetic valve. (replace)
Fault of hydraulic station (see common fault and troubleshooting 
of hydraulic transmission system)



Common fault and troubleshooting of gantry welding machine


Phenomenon Troubleshooting
Column goes only up not down limit fault (replace)
contactor fault (replace)
Welding flux cannot be recycled. Check the leakage of recycling system. Adjust and improve. 
Vacuum valve of recycling machine (replace)
Gantry cannot move. Broken synchronous belt (replace)
damaged motor (replace)
Inverter alarms (Adjust according to alarm No. in manual.)
Wire feeding belt usually be burn. It is not insulated between frame and welding flux. 
Check and adjust.



Common fault and troubleshooting of straightening machine


Phenomenon Troubleshooting
Bearing in guiding wheel is easy to broken. Certain distance should be kept to 
web plate during operation. (adjust)
The side work piece distorted a lot. (adjust flame)
No action of elevation Broken motor (replace)
fracture of elevating nut (replace)
Elevating silk pole and nut do not moves. (replace)
Elevating nut is easy to be broken. over-load operation (improve operation)
SN522 bearing seat is easy to be broken. over-load operation (improve operation)



Common fault and troubleshooting of Hualian welding device


Phenomenon Troubleshooting
Power supply is too small 
and the current 
of power supply cannot 
be adjusted.(200A)
 A. Lack phase (-380V output lacks phase.) 
 Check incoming line of main circuit.
 B. One-time voltage is too low (less than 340V). 
 Check the voltage of incoming line of main power supply.
 C. Loose plug-in. Check plug on main board (plug-in A1-A6)
 D. Damage of main board. (Replace main board.)
 E. Controllable silicon is damaged. 
 (Replace controllable silicon with the same modal.)
It stops welding after
welding for a period. 
This repeats.
 A. No feedback. Check whether 14-core (No. 4.10.11 line) fractures.
 B. No feedback. Check plug-in A1, A2 and A11 of control line board.
Current and voltage is out of control.  A. Wrong settlement of control switch of main body. Choose remote control.
 B. Wrong settlement of character switch of main body. Choose character of falling.
 C. Wrong settlement of switch of control box. During welding, it should be
  settled on “Welding”.
The silk cannot be feed in or 
out when debugging (manual).
 A. Wrong settlement of switch of control box. For welding wire, “Forward  or“Back” should be chosen.
 B. No “silk feeding in or out” signal. Adjust “Welding voltage” button 
 slowly until it feeds silk.
 C. Fuse. Check the connection of fuse pipe to motor and motor armature.
Unsteady arc voltage leads
to low current.
 A. Fracture of 14-core (It seems fracture but indeed not.). Check 14-core 
 with multi-meter one to one. Meanwhile, shake 14-core control cable and 
 check whether the pointer on Ω span of multi-meter swings.
 B. Bad contact. Check whether plug on the control side of main pole is loose.
 C. Bad contact. Check whether the contact between grounding line 
  (negative pole of welding device) and base metal is reliable.
There is no open-circuit 
voltage after pressing
Start button.
 A. Fracture of line inside 14-core. Check 14-core.
 B. Fault of main contactor of power supply. Check the main contactor and replace.
 C. Fault inside control box. Check whether plug-in inside control box is loose.
 D. Fault of control circuit board. Check group key IC2A. Replace.
 E. Fault of contactor. Check the JQX-14F inside control box. Replace.
When welding, arc voltage
cannot be adjusted.
 A. No feedback. Check whether No. 4 line inside 14 core is open circuit. 
 Start backup No. 14 line.
 B. No feedback. Check whether the A11 plug on control circuit board is loose.
 C. Fault of potentiometer. Check potentiometer of welding voltage. Replace.
 D. Check whether fuse of control power supply is burnt. Replace (1A)
no indication of control 
power, no action of 
control system
 Fuse of control power is burn. (on the bottom of control box. 1A)
Silk-feeding motor 
cannot rotate.
 A. Fuse. Check the fuse of silk-feeding machine.
 B. Lining. Check the lining of silk-feeding machine.
 C. Motor. Check whether the motor is fine.
 D. Check voltage of excitation and armature.
Silk-feeding wheels work 
but welding flux does not 
 A. Damage of silk-feeding wheels. Replace.
 B. Wire blocks. Welding wire blocks on plate. Replace welding wire.
 C. Bad welding wire. Check welding wire and replace.
unstable arc voltage,
bad formation of welding seam
 A. Conductive nozzle. Conductive nozzle is seriously damaged. Replace.
 B. Bond trap. Check the contact situation of positive pole of welding device.
 C. Bad contact between work piece and material frame. Check whether 
 there is paint or other insulator on material frame. Grind it.
 D. Check whether welding specification is correct. (Check current, 
 voltage, speed. Remove dust, oil and do drying treatment. )
The arc does not start.  Broken insulation. Check insulation between silk-feeding organ 
 and frame. Replace insulating gasket.