Drawing No1 : Examples of improved design using butt welded sections.
Drawing No2 : Venting an area enclosed by the continuous welding of a reinforced plate (a). If this is not possible stitch welding should be used (b).
Drawing No3 : External stiffeners on open sections should incorporate cropped corners or drainage holes to eliminate “dead pockets”
Drawing No4 : On vertical members, drilled holes or V notches should be diagonally opposite each other and as close as possible to the sealed end.
Drawing No5 : If holes can be provided in the location shown a cleaner blemish-free coating will be obtained
Drawing No6 : Holes should be positioned at the highest and lowest points on the section to ensure that no air is trapped during immersion and that drainage is complete during withdrawal from the zinc bath. Internal bosses should be omitted wherever possible.
Drawing No7 : Sections incorporating internal diaphragms and the end flanges must also be property vented. With small rectangular hollow sections, the four corners of the diaphragm plates should be cropped. Larger hollow sections should incorporate an additional “manhole” at the centre of the diaphragm.
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