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Request for information on the seven tank process

I would like to know where I can get information on the seven tank process, what I need to do and where can I get the materials. We are involved in Projects and we have been traditionally been using only Hot Dip Galvanising. I would also like some information on how these two processes will compare in the area of corrosion inhibition.

Jagannath Sarangapani
- Hyderabad, Andhra Pradesh, India
2003

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I don't know what you mean by "seven-tank process", but you might mean zinc phosphatizing because this is sometimes a seven-stage process. In that event, zinc phosphatizing is normally used as an undercoat for paint, and sometimes it is just oiled. The corrosion resistance does not begin to compare to hot dip galvanizing.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003

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Is it anything to do with the dance of the seven veils?

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2003

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2003

Re Trevor's comments ...

What has Salome to do with the 7 tank process? Aren't the 7 veils mid-Eastern, not Indian? Ah, I get it! It's a stripping process! We are all very confused, Jagannath, so please enlighten us. We are biting our nails in anticipation. Please excuse our aberrant humour.

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).

Hey guys,

Mr Jagannaths surname Sarangapanis' literal transalation would mean musical or dancing - water, please correct me if I'm wrong Mr JS! So everyone's answer may be appropriate after all!

In India, a pretreatment line with phosphating as the final coat, is popularly known as a seven tank process. Thank Powder Coating suppliers for this absurd simplification. If you add up degreasing, pickling and all the rinsing in between each process, then you are probably doing all that before your Hot dip bath. Its another name for zinc phosphate prior to Powder coating and is nowhere near Hot dip.

Khozem Vahaanwala
Saify Ind

Bengaluru, Karnataka, India

2003

Please tell me about 7 tank process; it is the process for surface preparation for coatings.

Sachin dev sharma
HOD in Paint industries - Delhi, INDIA
September 12, 2009