For effective galvanizing, cleaning solutions and molten zinc must flow without undue resistance into, over, through and out of the fabricated article. Failure to allow this can create complications for the galvanizer and the customer.
Improper drainage design leads to poor appearance, bare spots, and excessive buildup of zinc. All of these are unnecessary and costly. Communication throughout the project is key.
Where gusset plates are used, generously cropped corners provide for free drainage. When cropping gusset plates is not possible, holes at least ½-inch (13 mm) in diameter must be placed in the plates as close to the corners as possible (see Figure 7).
To ensure unimpeded flow of solutions, all stiffeners, gussets and bracing should be cropped at least ¾-inch (19 mm) (see Figure 8).
Provide holes at least ½-inch (13 mm) in diameter that can be placed in the web within ¼-inch (6 mm) of the end plate. To facilitate drainage, end plates should have holes placed as close to interior corners as possible. (see Figure 9)