How to do an insulation check (yearly task)?

Maintenance, cleaning and insulation check (can be used in general for any welder)

Procedure:

  •   Recommended to be done when the main Z-bar has to be changed anyway
  •   Time to do: 4 – 8 hours for 1 person
  •   Turn the main switch off, make sure the water cooling unit is also off!
  •   Take off the copper wire completely.
  •   Take off internal side seam tubes or internal oxyde tube.

 Tubes have to be insulated in the area of rollformer, to avoid any contact to the ground.

(In the area of the lower welding arm is a simple insulation not possible).
− Take off the grounding cable from the lower copper plate going to the welding transformer

    (Do not forget to place back after you finish).
− Clean the whole secondary circuit as good as possible by rag and compressed air.
 Blow from rollformer side towards overhead exit conveyor, to protect the bearings in the rollformer.

  •   Take off the lower welding arm.
  •   Dismount the main Z-bar including front nosepiece.
  •   Clean both Z-bars, the Z-bar slot in the arm carefully, without using grinding paper, to avoid increasing theinternal width!
  •   Check internal/external full ceramic cross bars for damages, no need to take them off, if they are ok.
  •   Clean the contact surface between arm and the copper plate going to the welding transformer with grindingpaper 400.
  •   Use a little flat plate and fold the grinding paper around.
  •   Not a must but recommended: Lubricate one of the contact surfaces slightly by copper grease(to avoid humidity in between. If you decide to do, do it on all other contacts)
  •   Check the O-Ring (to be done also on all following ones)

− Mount the Z-bar back into the arm and measure the insulation by Ohm-meter > 10 Mega Ohm!

  •   We recommend to use a special heat compound to guarantee a better heat transfer from the Z-bar to thewater cooled welding arm!
  •   We recommend to use new insulation washers (recommended also on all others).
  •   Check the little yellow full ceramic idler wheel in front of the lower welding roller, make sure screws/nutsare locked, and the circlip is not missing!
  •   Clean also the upper slot in the upper power plate.
  •   Take off the top copper plate between welding transformer and upper power plate (support of the lowerwelding arm). Clean the plate and the brown insulation plate (take care, can easily be broken).
  •   Clean all areas around the upper power plate, especially the area between power plate and copper plategoing to the welding transformer. This area is difficult to reach, when the lower arm is build in.
  •   Clean both areas between upper power plate and the main alumimium plate (devided by two brown

insulation plates).

  •   Clean the area around the big copper plate (going around the shaft of the upper pendulum rollerhead).
  •   Check following insulations (Ohm-meter > 10 Mega Ohm): Each idler wheel to the aluminium plate.

 Check also every bearing. Attention: Most of them have ceramic balls, marked by a red point!

  •   Each body of the copper profiling unit to the aluminium plate.
  •   The body of the big cooling wheel to the aluminium plate.
  •   The twin idler wheels (between rollformer and upper power plate) between itself but also to the aluminiumplate.
  •   Both transport rings, cutting wheel and pressing bearing/ roll of the wire chopper to the aluminium plate(clean up before may be helpful).
  •   The upper power plate to the main aluminium plate.
  •   The front support of the pendulum rollerhead to the aluminium plate.
  •   The welding pressure cylinder to the supporting plate.
  •   The main aluminium plate to the machine frame.
  •   The pendulum rollerhead to the machine frame.
  •   Calibration crown: Clean the calibration crown first.
  •   Each diabolo roller to the main brass plate.
  •   Support of guidance channel/calibration crown:
  •   Take off the whole canbody guidance including the long aluminium supporting plate (T-shape).
  •   Clean the whole area.
  •   Check the insulation between the long steel guide plate and its supports mounted to the frame:Three brown insulation plates underneath the long steel guide plate.
    Two separate brown insulation plates underneath a long steel bar (30/60 x 40 x 400 mm), to be found on the machine frame, in the area below the calibration crown.
  •   Put now back all parts.

 Make sure you are using only stainless steel screws and washers and lubricate the threads again!


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