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White spots on bright nickel finish

 

DEAR SIR

I'M INQUIRING THE POSSIBLE CAUSE OF THE WHITE SPOTS I FOUND ON MY PIECES. WE DO BRIGHT NICKEL FINISH OF SMALL PIECES (LIKE EYELETS) ON 2 FULLY AUTOMATIC BARREL GALVANIC LINES, AND IN SOME LOADS WE FOUND VERY MAKED WHITE SPOTS. WHEN THAT HAPPENS I CLOSE THE GALVANIC FOR THE WHOLE DAY AND IN THE NEXT DAY IT'S BACK IN NORMAL AGAIN. THE PROBLEM ARISES 2 OR 3 TIMES A WEEK. IF I DON'T CLOSE THE LINE THE NEXT CHARGES CAME NORMAL THAT AGAIN WITH WHITE SPOTS. SOME TIMES 30% OF PRODUCTION BECOMES DAMAGED. ANY SUGGESTION?

BEST REGARDS,

Ricardo Mota
- Vila Nova de Famalicˇo, Portugal

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I would need more information to establish what changes when the plant is switched off for the day: does the solution temperature come back to optimum? Does the rectifier cool off and work normal again? Do you have busbars overheating? Are the white spots the size of the barrel perforation? Is the iron contamination content checked and kept under control? Sorry! Only questions but they might point you to the solution of your problem!

All the best,

Trudy Kastner
electroplating service - Durban, KZN, South Africa