WIM RN-RB is formulated to help in the removal of hydrolyzed iron salts left on the pickled surface and not removed in a normal stagnant or flowing rinse.
Iron salts left on the steel can cause staining on continuous strip applications, or excessive iron build up in a preflux when hot dip galvanizing. A hot rinse is preferred with a range of 71 to 81 C (160 to 180 F). The hotter the rinse the better the reaction.
Where there is high humidity a stronger concentration is recommended and a hotter rinse. Depending on the circumstances, exceeding the preferred concentration and temperature may be advantageous during this period.
Charge at 0.2% by volume and maintain a pH of at least 2.5 or less and replenish when the pH reaches 3.
Add at the rate of 0.1% to 0.2% by volume of the overflow volume.
A heavy discharge of acid from the pickle tank into the stagnant rinse waters will have some effect on the pH control and when this is the case, daily or shift additions of the RN-RB may be in order.