Galvanizing plant - conditions for acceptance of the structure
Chemical composition
Galvanizing enables the anticorrosive layer of zinc to be applied to steel structures with a silicon (Si) content lower than 0.03% or within the range of 0.15% - 0.25%.
Surface condition
The surface of the structure should be free of slag, a thick layer of rust, welding spatters, welding slag, silicone anti-spatter agents, dirt with paints, greases and oils.
Design features
Hanging line:
Structures should be able to be suspended using hangers under the traverse.
The shape of the structure should allow free inflow of technological baths to all spaces and their free outflow.
Construction dimensions
Hanging line:
The dimensions of the structure must be smaller or equal to the dimensions presented - 2.8 x 0.8 x 1.8 m (length x width x depth).
With two dimensions close to the limit, prior consultation is required.
Maximum load weight up to 600 kg per 1 traverse, maximum load size up to 1200 dm2 per 1 traverse.
Drum line:
Minimum load 20kg per drum
Vent holes
Structures made of elements with a closed cross-section should have vent holes, allowing free inflow of technological baths during immersion and their free outflow during the emergence of the structure at individual stages of the process. The table below shows the size and number of vent holes in the structure elements.
The vent holes can be made as triangular or semi-circular cutouts in the profile walls. The drawings below illustrate the rules for placing vents.
Internal dimensions of closed profile in mm smaller than: |
Minimum diameter of holes in mm at opposite ends of the profile and their number: |
||||
---|---|---|---|---|---|
round | square | rectangular | 1 | 2 | 3 |
15 | 15 | 20 x 10 | 8 | – | – |
20 | 20 | 30 x 15 | 10 | – | – |
30 | 30 | 40 x 20 | 12 | 10 | – |
60 | 60 | 80 x 40 | 20 | 12 | 10 |
80 | 80 | 80 x 60 | 20 | 18 | 12 |
100 | 100 | 120 x 80 | 25 | 20 | 12 |
120 | 120 | 160 x 80 | 30 | 25 | 16 |
160 | 160 | 200 x 120 | 40 | 25 | 16 |
200 | 200 | 260 x 140 | 50 | 30 | 16 |