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Unknown losses in zinc kettle even with no production

April 13, 2009

Dear All,

This is Karu again [letter 51644 on basket material, letter 51659 on H2O2]. My case is we heat the zinc up to 565 °C.i would like know the following points.
1.Are there any kind of unknown losses in zinc if how much , because I observed reduce in zinc level in the kettle even though there was no production.

2. I am getting 85-100 microns thickness on all kind of fasteners. we galvanize from (565-540 ) degrees.And kettle to centrifuge transfer time is 5 sec.

Please suggest me regarding these issues.
Thanks in advance

Regards,

Karunakar Gandla
employee - Vizag, Andhra Pradesh, INDIA

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April 14, 2009

Sir:

1) I suspect you have a hole in your kettle. The zinc is far too hot.

2) The temperature of the zinc is far too hot.

Regards,

Dr. Thomas H. Cook
Galvanizing Consultant - Hot Springs, South Dakota, USA

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My immediate thought was a kettle leak too.
If this isn't a ceramic kettle, but a steel one, then the zinc temp is too high (as said above). The zinc will dissolve the kettle in no time at this temp, and leave you with zinc in a sieve!

Geoff Crowley
Crithwood Ltd.
Westfield, Scotland, UK

April 15, 2009

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Dear Sir,

Please let me know how much temperature should I maintain I mean zinc temperature.

Still will be there any unknown losses

Regards,

Karunakar

Karunakar Gandla
- Visakapatnam, INDIA
April 19, 2009

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April 20, 2009

Sir:

If you are using a steel (iron) kettle and doing NORMAL galvanizing the usual temperature in North America is about 840 F (about 450 C). If you are using a ceramic kettle and doing high temperature galvanizing, I do not immediately know what is the usual temperature.

If you are using a steel (iron) kettle and you have a leak, it will not likely get better, but is likely to get much worse. If the leak is high up then the leak will stop when the zinc level equals the leak height. I have little experience with ceramic kettle leaks. Most leaks show themselves by much white smoke coming out the waste gas stack from the burners.

Regards,

Dr. Thomas H. Cook
Galvanizing Consultant - Hot Springs, South Dakota, USA