If the overlapped parts cannot be avoided, a hole 10 mm in diameter for every 100 cm2 is fitted (Fig. 12). This requirement is of particular importance when using thin materials.
Ventilation openings for steel with a thickness greater than 10 mm and an overlap area greater than 300 cm2 must be agreed with the galvanist before production. The ventilation openings in both parts will increase the quality and ensure the safety of galvanizing.