Double Dipping

Double dipping is a process used by galvanisers when a steel fabrication is too large or otherwise difficult to fit in their bath at just 1 angle. In simple terms, the fabrication is dipped more than once, at different angles to ensure that all of its surfaces receive an adequate coating of zinc. It is not a technique to increase coating thickness.

Newsflash: We have made a new video on double dipping, which you can watch along with other useful clips here.

There are some important points to consider when using double dipping to galvanise large steel products:

  • Adequate draining for the steel at multiple angles has to be considered both from a safety and quality perspective.
  • The fabrication has to be able to be suspended safely at all required dipping angles.
  • When multiple dips are carried out for a single steel fabrication, there can be an overlap of zinc layers which can cause a faint visible line, but this will generally fade overtime.

double dip article 2

 

Korvest Galvanisers uses in house technical staff who can solve any related problems that may arise from the above. Often it is extra long, otherwise large or angled steel fabrications that need to be double dipped. 

Steel fabrications that have been dipped multiple times to cover all surfaces still conform to the AS4680:2006 standard.

Double Dipping

Structural steel fabrication emerging from the bath after a second dip at a different angle