Flux 657 is a water-based, inorganically activated liquid flux designed specifically for heat exchange.  This water soluble product provides excellent wetting, as well as minimal residue.  It also provides a high dilution ratio, and is zinc chloride free. The flux is for high speed tinning and soldering. Applications such as tube mills and strip-tinning lines will achieve reduced pitting and full-flow soldering. The flux residues during soldering will also reduce oxide formation on the solder pot as it works as a pot blanket as it is consumed.