Support

8 Support Entries

Download PDF here

German instruction: page 52 – 55

English instruction:  page 110 – 113

French instruction:  page 172 – 175

Possible cause:

  • Check if the blank cutting is correct.
  • Check if the overlap is correct and constant.
  • Check the welding sensor B6.
  • Check the welding pressure sensor S31:
    • depending on your version S31 is a pressure sensor or a reed switch!
  • Check if the wire has no dent’s (mechanical damage for example due to too big can gap).
  • Check all terminals at the Pacemaker board.
    • > wait for 5 minutes after switching off the unit.
  • If you can weld a canbody with only main current and the error occurs quiet often, you can try the following:
    • a) remove the welding sensor.
    • b) start production and cover the sensor by hand, as soon as canbodies are welded.
  • Open the rollformer, and put a piece of wood between the rollers (for safety)
  • Only if weld pressure by spring: Release the spring pressure of the welding pressure completely
  • Stop the main air supply
  • Switch of the main power supply
  • Stop the cooling unit, take off both water pipes from the lower weld arm (long copper bus bar)
  • Take off the lower weld arm by taking off the copper plate (on transformer side) and loosen all bottom M5 screws.
    It might be needed to take off the idler wheel in front of lower weld roll as well
  • Undo both bottom M5 screws (type: Flat head, thickness 1.5 mm) of the T Z-bar
  • Undo both M6 screws (through side plate of rollformer) which is holding the support above T Z-bar
  • Undo four M5 screws which are holding the T Z-bar over its top support
  • Clean the slot in which the T Z-bar is going in by air pressure if needed
  • Clean the surface on the rollformer side plate if needed. Don’t use sandpaper with your fingers. If needed use a grinded plate to support the sandpaper.
  • Grease the T Z-bar and the slot and mount the T Z-bar by the bottom two M5 screws. Don’t tight them yet!
  • Mount the top support by four M5 screws, and push the support (and T Z-bar) towards the rollformer side plate
  • Check now the top and bottom gap between side plate and support by feeler gauge 0.02 – 0.04 mm: There shall be no difference
  • If there is no gap, tight first the bottom screws, then top screws, then screws through rollformer side plate
  • Undo the bottom screws and tight again
  • Clean all bottom flat head M5 screws if needed (they become rusty), and grease their heads
  • Mount the lower weld arm. Make sure that the insulations of each screw are not damaged. Lubricate each insulation if they are made by shrinking tube
  • Put a piece of paper board between the weld rolls and measure the insulation
  • Connect the lower weld arm on the transformer side by mounting the copper plate between and connecting the water pipes
  • Switch on water, air and power supply
  • Feed in the profiled copper wire compeletely
  • Only if weld pressure by spring: The gap between both weld rolls shall be not bigger than 2.0 mm (enough to feed-in two profiled copper wire). Adjust if needed by the M6 threaded bolt / nut
  • Adjust the air-throttle on the weld pressure cylinder to make sure that the piston is coming down as slow as possible!
  • Test it first by activating the solenoid valve
  • Only if weld pressure spring: Adjust now the spring: If the weld rolls are closed the compressed spring shall have a length of about 55 mm (length of uncompressed spring
    measures 80 mm. 5.5 mm are equal to 10 kg / daN)

Possible causes:

  • T-Z-bar broken
  • Z-bar cooling insufficient (if not existing on your welder, ask us for a upgrade kit)
  • Welding frequency too high (ask us for a Pacemaker upgrade: change from triangle to sine wave welding)
  • Not enough cooling water (check proper adjustment of water flow switches)
  • Cooling water too warm

Download PDF here

Possible cause:

The encoder signal for the production speed of the inverter U7 is coming from a external encoder mounted on the downstacker. On the shaft of this encoder there is a small white plastic gear wheel mounted. Please check the screw of this wheel, it might not be fixed well.

> See picture below to find the encoder.

Report all steps, new or different settings, old and new production parameters (can size, cpm, weld speed, weld current, weld frequency, current wave-form and transformer step) for an easier overview and follow-up!

Open a new ticket and add your document!
Note on which tin-plate parameters (thickness, hardness, tin coating inside / outside, rolling direction, BA or CA, supplier, printed or not) such faults occur, and on which tinplates not!

Basic parameters & settings to be checked first

  1. Tin-plates must be cutted within the allowed tolerances:
    • Measure the tin-plates and report if out of tolerance!
    • Follow sheet „blank-cutting tolerances“!(www.canman.ch/SUPPORT/Canmaking/002)
    • Are all tin-plate parameter clear and noted: Thickness, hardness, tin coating in and outside, rolling direction, BA or CA, supplier, printed or not
  2. Can-bodies must be correct rollformed:
    • Not conical and best roundness must be reached!
    • Overlap of both tin-plates edges:
      • ø52 ~ 5mm
      • ø99 ~ 15mm
      • ø153 ~ 30mm
      • ø284 ~ 60mm
  3. The copper wire must be correct profiled and the surface not damaged:
    • The width of the profiled copper wire shall always be 0.05 mm smaller than the profile-groove in the weld rollers!
    • Measure the width of the profiled copper wire within around half a meter on several position, and note the variations. Maximum difference of 0.05 mm are allowed. If you measure more, check the concentricity of the profiling rings.
    • Change the copper wire profiling rings or idler/guide wheels if the surface of the copper wire shows a damage!
  4. Both weld rolls must be regrooved after its regular groove life-span:
    • To avoid unexpected heavy weld faults it is recommended to implement the total piece-counter and the regrooving interval into the production order!
    • As an example:
      • Upper weld disc ø 90 mm to be regrooved after 3 mio cans (interval depends on, type of welder, type of weld roll and welding speed).
      • Lower weld roll ø 62 mm to be regrooved after 2 mio cans.
      • Total piece counter at production start at 28 mio welded can bodies, upper weld disc has been regrooved at 25 mio, therefore to be regrooved now! Lower weld roll regrooved at 27.5 mio, therefore to be regrooved at 29.5 mio.
    • After every regrooving weld roll and / or z-bar must be repositioned: Use the correct to reset the lower weld roll and/or nose-piece, and the upper welding roller!
  5. The z-bar must be clean in and outside – and not worn -, calibration crown must be clean, and are all pre-calibration rollers shall turning easily:
    • A dirty z-bar may not be well insulated, therefore the risk of wear is higher and the weld current is flowing over z-bar and tin-plate to the weld center!
    • Note: The insulation of the secondary circuit should be controlled yearly!
    • Non turning pre-calibration rollers can create body-offset and unconstant can gap!
  6. The calibration crown center must be correct positioned to the weld center:
    • The center of the crown must stay between 3 – 1 mm before the center of the lower weld roll (in weld direction seen).
  7. The position and speed of the exit conveyor (all conveyors which transport the can body out of the weld center) must be aligned perfectly.
    • Both belts have to touch the can body similar. The direction of the conveyor must be absolutely parallel to weld direction!
    • The gap between two can bodies on the exit conveyor should not be higher than10 – 20 mm! (if can gap is 1.5 – 3.0; see „can gap“ in point 12.)
    • A driven diabolo roller must run the same speed like the copper wire!
  8. Both tin-layers must be centered and parallel on the copper wire:
    • That means that all mechanical settings are correct!
  9. The copper wire tension and elongation must be correct:
    • Make sure that the air-pressures for the pneumatical cylinders are set correct, or the copper wire is in the right groove of the wire drive disc (Soudronic m/c’s only).
    • Measure the copper wire elongation after the lower weld roll, or after the weld roll before the wire chopper: Elongation varies between 0 – 4% of the can body height.
    • A sufficient copper wire tension is important to avoid a sliping copper wire on the weld rolls!
  10. The can body overtravel must fit:
    • Set the overtravel according manual / scale on the transport carriage!
    • Measure how many mm the can body will be pushed over the center of the weld rolls.
  11. The welding pressure must be set correct:
    • Welding pressure for Wima welders vary between 35 and 50 kg / daN. Start with ~ 45 kg / daN. Check the manual to convert in bars.
    • 50 Hz welder using welding pressures between 35 – 45 kg/daN, while automatic welders running between 40 – 50 kg / daN.
  12. The welded overlap must be correct, and on begin and end within allowed tolerance:
    • Correct welded overlap depending on z-bar:
      • Z-bar of 0.4 mm results in a welded overlap of 0.5 – 0.6 mm
      • Z-bar of 0.6 mm results in a welded overlap of 0.7 – 0.8 mm
      • Z-bar of 0.8 mm results in a welded overlap of 0.9 – 1.0 mm
    • If the overlap is not correct, adjust until overlap is correct:
      • Reset the calibration crown if needed with the mandrel. The diabolo-rollers should not have any radial-play!
      • Adjust the overlap according manual.
    • Once the overlap has been set, double check and set the can gap. Increasing the overlap will reduce the can gap, decreasing the overlap will increase the can gap.
    • Weld around 5 cans and measure the gap between the tin-layers. A good can gap measures between 1.5 – 3.0 mm. Any variation should be within 0.5 – 1.0 mm.
  13. The weld current frequency must fit:
    • Welders with a static frequeny inverter should have a welding spot length between 0.6 – 1.2 mm.
    • A welder without static frequency inverter should be operated between 8 – 12 m/min. Reducing the welding speed does decrease the welding spot length.
    • The welding spot lenght should always be as long as possible (by reducing the frequency) to reduce energy and heat in the welding seam and in the welder to a minimum.
    • Main target must be a flexible and smooth welding seam!
  14. The main weld current must be set correct!
    • How to do:
      • Reduce weld current until cold weld zones appear. Tear-off test must be done at an angle of 30 – 45°, means try to pull-off the top tin plate edge. To be done from each side. Note the weld current value!
      • Increase weld current until hot weld appears. Tear-off test must be done at an angle of 0°, means pull-off the seam only and find out when the seam starts to become fragile. Note the weld current value!
      • Add 2/3 of the weld current difference between cold and hot weld seam to the cold weld seam value, and start the production!
    • Set beginning and end time and beginning and end current!
    • Note: If the welder is running with triangle wave-form, make sure the duty-cycle is between 80 – 90%. If the welder is running with sine wave-form, make sure the right transformer step has been choosen! Contact us if you are not sure.
  15. The seam-extrusion inside and outside must be equal!
    • If the seam extrusion is bigger inside, reduce the height of the calibration crown. If the seam extrusion is bigger outside, increase the height of the calibration crown.
    • The shape or roundness of the can-body is not so important as a correct seam-extrusion!
    • The seam extrusion inside depend on the inner weld roll diameter as well: The diameter difference of upper and lower weld roll should be as small as possible.

 

Checklist to avoid micro leaks

Micro leaks can occur within the seam and beside the seam – especially on cold-formed areas like necking, beading, flanging or seaming -, even if all above mentioned basic parameters & settings seems to be correct.
Micro leaks can have various sources: Wrong settings on the welder, tin-plate parameters which support such faults, worn or wrong machineries in the downline, or tin-plate parameters which do not fit to beader, necker, flanger and seamer.

For a better visual understanding put the faulty-can bodies in a water bath, and inspect the leaking area by a microscope. Store the pictures if possible!

  1. Make sure that necker, flanger, beader and seamer are in good conditon, and do not stress the weld seam more than needed.
    • For further information check the manuals (check the tin-plate specifications range) or contact the supplier!
  2. Try to weld different tin-plates to understand which tin-plate parameter can be produced without such faults.
    • Rolling-direction parallel to weld seam can increase the occurence of micro-leaks!
  3. Micro-leaks in and near the seam can be reduced by changing the energy in each welding spot:
    • Reduce the welding frequency within the possible range (see point 13. in above checklist), and set the main weld current again (see point 14. in above checklist). The production cycle (cpm) must probably be reduced to reach a good weld seam. Produce a certain number of cans and test them.
    • Increase the welding frequency within the possible range, and set the current again. Produce a certain number of cans and test them.
    • Reduce the welding pressure to max 45 kg / daN, and set the main weld current again (see point 14. in above checklist). Produce a certain number of cans and test them.
    • Reduce the welded overlap by around 0.10 mm, and set the main weld current (see point 14. in above checklist). Produce a certain number of cans and test them.
  4. If above listed does not help, some theoretically wrong settings could help:
    • Increase the can gap to have completely different welded begin and end. Produce a certain number of cans and test them, and set back if it didn’t helped!
    • Set a slight can-body offset, to bring the current different into the tin-plate. Produce a certain number of cans and test them, and set back if it didn’t helped!

 

Download print version

  • Empty the water tank. On 2-circuit cooling unit only cold water tank has to be emptied.
  • Blow off one by one each cooling circuit in the welder. This allows to empty each circuit separately. If your welder has a 2-circuit cooling system only the circuit for the lower and upper weld roll has to be emptied.
  • Change the filter cartridge and clean the filter housing inside.
  • Fill the tank with water only, open main valve Y14, and run the system for at least one hour to flush rests of old emulsion out.
  • Empty the water tank again and clean again if necessary.
  • Fill the water tank with water (or distilled water if requested), and mix the PowerRoll™ coolant H1 in with 8 percent.

We recommend following maintenance procedures:

  • Change the filter cartridge monthly.
  • Change the cooling emulsion yearly. Use the PowerRoll™ cooling system cleaner at any time you change the emulsion.
  • Use the PowerRoll™ cooling system decalcer after around 5 years.

Order numbers:

  • PowerRoll™ coolant H1 (food grade), 7 Liter, 011494
  • PowerRoll™ cooling system cleaner H1 (food grade), 10 Liter, 011495
  • PowerRoll™ cooling system decalcer, 25 kg, 011496
  • Filter cartridge 50 µm, 002446

Safety data sheets see below: