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HOW TO REDUCE TRI CHROME CONTENT

adv.    

HI,

I AM RAZA, ASST. IN CHARGE OF PLATING SECTION. WE ARE INTO FLEXIBLE PACKAGING SO WE HAVE AN INHOUSE CYLINDER MAKING FACILITY TOO, WHICH INCLUDES A WORKSHOP, PLATING SECTION AND ENGRAVERS. I NEED TO KNOW HOW TO REDUCE THE TRICHROME CONTENT FROM THE CR ELECTROLYTE. THE LEAD STRIP IS ALREADY FIXED WITH THE ANODE BASKET AND I HAVE EVEN TRIED CUTTING OUT THE ELECTROLYTE AND ADDING NEW BUT AFTER A WHILE IT AGAIN STARTS TO RISE AND AT THE MOMENT IT IS AROUND 10.5. ANY SUGGESTIONS.

RAZA HUSSAIN
ASST. IN CHARGE PLATING SECTION - KARACHI, SINDH, PAKISTAN
2004

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First of two simultaneous responses --

Formation of trivalent is normally caused by too little anode area for the cathode area, such as plating ID's. The next contributor is voltage. You will form less if you can up your voltage. 0.1 or 0.2 volts increase can make a difference. Next, if you can decrease your anode to cathode distance, it will form less. You will always get some formation, what you are trying to do is to reduce the rate that it is formed. Organics will break down hex to tri also. Finally, a cure, is to use a porous pot, which will also remove a lot of your trace metals, particularly iron, which will give you a better plating efficiency-all else equal. I used cheap ones from Hard Chrome Consultants in Cleveland, Ohio. I have no idea who could provide suitable affordable ones in your country.

James Watts
- Navarre, Florida
2004

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Second of two simultaneous responses --

Have you tried a porous pot?

James Totter, CEF
- Tallahassee, Florida
2004

I am thankful to both person responding to my query. I am sorry never heard of Porous Pot, how does it help in reducing the trivalent?

SHAIKH RIZWAN
FLEXIBLE PACKAGING - KARACHI, SINDH, PAKISTAN
2004

It is a cylindrical ceramic pot (special material) that will allow ions to migrate thru it. It is filled with plating solution, set in the tank and has an electrode on the outside and the inside of the pot. When hooked up correctly to a power supply trivalent chrome goes to the inside as well as some metallic ions. Works very well. Check with some of your plating supply houses in your region. Surely one of them can get one for you. Some are not cheap!

James Watts
- Navarre, Florida
2004

Normally you can request this kind of porous pot with your chemical supplier, normally is used in the pot sulfuric acid 10% with a copper anode the basket is lead and the voltage normally is 6 Volts and low current.

Gabriel Ramirez Nuñez
- Toluca, Mexico
2004

Hi Raza,

I agree with all the above; however if you have never heard of a porous pot it might be easier to plate out the trivalent chrome. Use a scrap cathode rod and 16 times more surface on the anodes and plate out at normal plating voltage for a few days (or nights). Make sure you use fume suppressant and fume extraction to prevent chrome spraying all over the factory!

Good luck!

Trudy Kastner
electroplating service - Durban, KZN, South Africa
2004

adv.