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Chrome line life expectancy

I am purchasing a functioning Chrome line and our bank wants to know the life expectancy of the line. The main pieces in question are the tanks and the rectifiers. In your opinion, what is the average life span of propylene tanks in a Chrome line? This will be used for show chrome. We have 1 HBS 5000 amp, HBS 200 amp and 2 rapid electric 1500 amp rectifiers. I understand that the tanks will last a lifetime as long as they are maintained correctly and the rectifiers are rebuildable. I would just like an expert opinion. Any input is appreciated. Thanks!

Ben Ramirez
Plating shop owner - Dallas, Texas
May 19, 2008

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Hi ,

If you take care of the tanks / vats , they could last many many years - (2 of mine are 25 years old and good as new )
its all down to good house keeping and keeping them clean .

also its better to pay extra for decent tanks , as my new 1 is in need of repair after only a year - the lining has perished , which means the chromic acid can attack the steel tank . I believe you can buy double lined tanks so that may be worth looking at .

as for rectifiers , they can last a life time , but will probably need minor repairs from time to time .

I have probably only said what you already know but I hope I've been helpful .

Jay Smith
- Essex, UK
May 20, 2008

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May 21, 2008

I know that polypropylene will not stand up to some chrome plating solutions that use a proprietary additive. I know of one that is OK and one that will destroy the tank.

IAs far as a used polypro tank, I would not do it. The chrome attacks the plasticisers ofer a long period of time and it has a high probability of getting millions of stress cracks that in time will open up to be a real crack.

The welded in black liner (high priced) did not last 2 years in two tanks. A thick vinyl liner with a skirt at the air liquid interface and a second bottom to cushion dropped parts lasted several years and was still in good condition when I left.

James Watts
- Navarre, Florida

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May 23, 2008

Do not use polypropylene for hot concentrated chromic acid solutions. It will stress crack.
Use halogenated plastics like PVC, Koroseal

Geoffrey Whitelaw
- Port Melbourne, Australia

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May 27, 2008

A drop-in lining and extractor can stand in average of ten years. Rectifiers if in good environment and cooling can go for ever. A drop-in PP lining price was around two to three thousands,some years a go,.
Good luck and God bless

Khair Shishani
aircraft maintenance - Al Ain, UAE