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Why not mix the chemicals and do 7-tank process in one tank?

2007

Dear Sir,

We are Planning to have a 7 Tank process which is a pre-painting process over MS Tanks. We dip in different tanks at a specified period of time. Derusting, Degreasing, phosphating and passivation treatment will be done at different intervals, each at high temperature. Instead can I mix all the chemicals in a single tank and dip the metal parts for longer time. This saves us power consumption. Sir,Can any one help me in knowing the advantages and drawbacks of the proposed system.

Also, can we do 7 - Tank process (Derusting, degreasing, phosphating and passivation treatment) in cold water rather than in hot water at high temperature. Sir, any one can suggest in this regard. However, the quality shall remain unchanged?

Sampath Kumar
OWN - HYDERABAD, ANDHRA PRADESH, INDIA

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2007

Hi, Sampath -- welcome to the forum! But I will be turning down your invite for a 7-course dinner :-)

A 7-tank process is the ultimate in pretreatment (clean, phosphatize, post-dip, and rinses). It is also possible to do a 5-tank process (clean, phosphatize, and rinses) or a 3-tank process (combination clean and phosphatize, and rinses).

But you must make a conscious choice to reduce the number of steps by simply not doing some, and optimizing the chemistry for the process steps you are actually doing; you don't put a slice of chocolate cake in the soup :-)

If the quality and cost of the simpler process matched the more elaborate process, no one would do the more elaborate. The simpler process may be fully adequate for your needs, but it will not be as good. Good luck, and if you tell us the application we may be able to offer further recommendations.

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

To cut seven tank process what is alternative process, we want to cut seven tank process, what is solution for directly coating primer and into paint.

D.Vasu
production - Chennai, Tamil Nadu, India
February 1, 2008