The internal leveling machine is an essential equipment on stainless steel pipe making equipment, used to remove the internal welds of welded pipes and improve the quality level of welded pipes. In addition to understanding the possible faults that may occur with the internal leveling machine, it is also necessary to understand the fault diagnosis and resolution methods when using the internal leveling machine.

Fault type: Inner leveling trolley does not move forward (backward)

Possible causes: 1. If the trolley does not move under the manual and automatic mode, it may be that the intermediate relay controlling the forward (backward) direction is faulty, the valve is broken, the two proximity switches for reversing are short circuited, and the Potentiometer is damaged. 2. If the car can move in manual mode, it may be due to a remote connection without a signal, no signal to the X13 input point of the PLC, or a malfunction caused by a faulty proximity switch.

Analysis method: investigation method (arranged according to likelihood)

1、 In manual and automatic mode, the inner leveling car does not move

1. In this case, the most likely cause of the inner leveling car not moving forward (backward) is a malfunction of the inner leveling machine valve. However, it is worth noting that it is not necessarily a valve issue if the inner leveling car does not move, but it may also be other issues. It is easy to determine if there is a problem with the valve. Simply set the control box to the manual up position, and then use a screwdriver to poke the coil thimble of the proportional valve that controls the front and rear to see if the car is moving forward (backward). If the car still doesn't move, it's a problem with the valve. In this case, the user can remove the valve pressure, then remove the valve and valve seat, clean them with diesel, and then install them back. If the cleaning is completed and the car is still installed, you can try removing a valve from another device and putting it on. If the car can move, it is a problem with the valve spring. Users can choose to replace it with a new valve or send it back to Henkel for maintenance by our engineers.

2. Secondly, the possible cause of the inner leveling car not moving forward (backward) is a problem with the intermediate relay that controls the forward (backward) movement. To determine if the internal leveling car malfunction is caused by a relay, simply replace the relay and try it out. If the car can move, then there is a problem with the relay. Simply replace the relay. If the car still doesn't move, it is basically ruled out to be a relay problem, and the next possibility is to check.

3. The third possible cause of the inner leveling car not moving forward (backward) is a short circuit between the two proximity switches for reversing. To determine if the fault is caused by a short circuit between the two reversing proximity switches, the replacement method can also be used. You can replace the leftmost and rightmost proximity switches and try a good one. If the car still doesn't move, this possible cause can be basically ruled out. If the car moves, it is determined that the proximity switch is short circuited, and only the proximity switch needs to be replaced.

4. The fourth reason that may cause the inner leveling trolley not to move forward (backward) is that the Potentiometer is damaged and there is no voltage input. Judgment method: Measure the voltage between PIN and U0 or FIN and U0 with a multimeter to see if it is 1-10V. If there is no voltage input, it means that the Potentiometer is damaged.