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Quick Question: Typical Tinplating steel cathode surface area?

Please tell me the average surface area (or a general range)of a steel cathode used in the electrolytic production of tinplate, using a stannous fluoborate electrolyte. Leave a name so I can reference you for my school project. I desperately need this information so that I can carry out calculations. So far I have discovered a typical current density to be 24.3 miliamperes/centimeter squared, and need a figure for overall current - to do so, I must find the cathode surface area!

C Forrester
- Australia
1999

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Continuous tin plate on coil coated steel might typically be done on a 48" wide coil.

So the sheet will be 48" (1.5 meters) wide, (let's say only one side is tin plated, the other side being left untreated.)

But the tin is plated continuously, that means the coil is unwound on one side of the machine, winds through the plating tank and is wound up, plated, on the other side. The tank may typically be 100 feet long (30 meters) but may easily be 60 meters long. tom

  
Tom Pullizzi
Falls Township, Pennsylvania
1999

Thanks, that's exactly what I needed to know. One thing I'm wondering about though - how is one side of the coil not plated? Is it not immersed? Please explain!

Catherine Forrester
- Australia
1999

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It is immersed, but without proximity to anodes, only a miniscule amount of current will carry around to backside. You can, however, plate both sides by arranging your tank so that the sheet passes in between two sets of anodes.

  
Tom Pullizzi
Falls Township, Pennsylvania
1999