A Zn-Al based paint is recommended for touch-up of weld zone and cut ends.
Examples of touch-up paints
Paint name
Manufacturer
Type of paint
Color
Roval Silver
Roval Corporation
Zn-Al based
Silver
Zinky special
Nippon Paint Anti-corrosive Coatings Co., Ltd.
Zn-Al based
Silver
O-well Mekki Silver (ZAM™ color)
Nihon Ruspert Co., Ltd.
Zn-Al based
Silver
・Notes
1. Details of touch-up paints including their proper use, quality haracteristics, and compatibility with environmental regulations should be checked with respective makers.
2. In some cases, painting is not possible over touch-up paints. Be sure to check beforehand.
Corrosion resistance of weld zones after touch-up
Satisfactory corrosion resistance can be obtained by touching up the weld zones in an appropriate manner.
Appearances of touch-up painted areas after combined-cycle corrosion test
Thickness: 2.3 mm, coating weight: 85/85 g/m2
Paint: Zn based
Paint: Zn-Al based
Sample of welding method
Welding method: CO2 arc welding Joint shape: Butt welding
Painting method
Pre-treatment: Wire brush Degreasing: Organic solvent Painting: Brushed on Drying: 60°C, 10 min Film thickness: Approx. 40μm
Test conditions JASO M609-91
Corrosion resistance of cut edges after touch-up
Additional corrosion resistance can be obtained by touching up the cut edge.
Appearances of touched-up cut edges after combined-cycle corrosion test