Metal finishing Q&As since 1989

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Alkaline zinc plating

I am using alkaline zinc plating ,

I use raw water only,

if use continue raw water which type of problem will come,

I need clarification about impurities in the raw water.

Guna Sekaran
Plating shop employee - Chennai & India
April 15, 2008

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Hi, Guna. What problems would come if you made soup with this water? :-)

Lots of people use raw water if it is not terrible. But the best path is to keep moving forward and to decide that you need RO or DI water because this junk doesn't belong in your plating tanks. It is difficult to say exactly what problems would result from use of water of unknown quality; excessive calcium, chlorides, iron, and the other things in raw water are contaminants that eventually spoil the plating solution. You would have to study what contaminants are in the water and in what concentration, and whether this is close to or far less than the technical data sheet suggests as troublesome.

Sorry that I don't have a "real" answer for you.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
April 15, 2008

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Dear Gunashekaran,

Raw water if not really good say not of good quality will give a yellow tint to plating and this will continue to show if blue passivated.Genarally supply houses will supply a conditioning agent to deal with such impurities from water.The best is as Ted said, invest in a DI/DM water generating equipment. But make sure you give a sample of water presently used to the equipment maker.
Good luck

T.K. Mohan
plating process supplier - Mumbai, India
April 17, 2008

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Dear Friend,

Using DI/DM water is advisable. But if you hardness is moderate, in some cases you can use water softening chemicals in your bath.

Hope you are in Chennai and it is diffucult as the hardness is more in your case.

Please opt for DM/DI water.

Thanks

S.V. Aurobind
plating process supplier - Bangalore, India
May 9, 2008