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SOLUTIONS: Cast Iron

low. If there is excessive spatter and undercutting, the amperage is set too high.

attached to the workpiece itself if possible.

Desired Bead Contour.

For Unitor NICKEL-333N and Unitor NIFE-334N amperages should be set approx. 10% lower than those used with conventional cast iron electrodes. Recommended amperages are as follows: Unitor NICKEL-333N - 2.5 mm 55-110 Amp.

- 3.2 mm 80-140 Amp.

Unitor NIFE-334N - 3.2 mm 75-100 Amp.

- 4.0 mm 85-160 Amp.

The above settings are approximate. Setting will vary with the size of the job, type of machine, line load, etc. It is recommended practice to select a setting halfway between the figures and make a trial weld. NICKEL-333N has high ohmic resistance. If ampere setting is too high the electrode may become red hot.

In general, the welding current should be as low as possible, consistent with easy control, flat bead contour, and good wash at the edges of the deposit. The amperages listed are for flat or downhand welding positions. Reduce the amperage range by 5-10% for overhead welding, and about 5% for vertical welding.

Choice of polarity

2.07

If the current source for the welding is a welding rectifier (DC-machine), the choice of correct polarity will influence very much on the result of the work. Some electrode manufacturers make cast iron electrodes that can only be used with negative polarity. Furthermore, some years ago the general low quality of cast iron electrodes made it necessary to use negative polarity to achieve binding between base material and weld deposit. However, the quality of Unitor cast iron electrode is very high, and the electrodes can be used with both polarities without difficulty. The operator must be aware of the effects of the different polarities, as the heat input and the melting of the base material varies considerably according to the polarity selected. Straight polarity (Cathode)

Reverse polarity (Anode)

To ensure good electric conductivity the return cable clamp should be

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