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Hot dip galvanizing of tubes

2003

Hello.

We have a hot dip galvanizing plant. We are starting to galvanize tubes of Ø1/2" to 1.5" by batch. Can some one give me ideas for the jigs or the way to hang the tubes in order to maximize my efficiency. I would like any tips to reduce the coating thickness, or for the whole process.

Thanks,

Juan Carlos Sanin
galvanizer - Medellin, Antioquia, Colombia

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This is difficult to answer without a picture. Batch galvanizing of tubes can be done in two ways: when it is allowed to drill holes in the tube you can use different lengths of steel wire to hang the tubes.

When it is not allowed to drill holes you have to use a frame(cage) with removable grid frames (when it is possible with the length of the tubes one at each side). The grid size depends on the diameter of the tubes.

The pre-treatment can be done in the total frame including the grid frames. At the end galvanizing can be done with the grid frames alone (galvanizing with to whole frame will cause a lot of zinc-loss and excess of zinc in the pretreatment).

Dolf van den Berg
- Leusden, The Netherlands
2003