Am Freitag, 6. Oktober 2017 12:25:31 UTC+2 schrieb David Billington:

Here is a venting guidance video from Wedge Galvanising
http://www.youtube.com/watch?v=C8EGUlerwVg , it include brief footage of
what can happen when an unvented items is dipped and it bursts.

Great video. It explains a lot of small structural features on fabricated structures. Thanks to everyone for the responses. Interesting thread.

By the way, does anyone know why the cut-out on this excavator dipper is provided? I figure it might be something to do with stress distribution and fatigue resistance, but I can't work out why this cut-out location would help. Maybe it has another purpose. Any ideas?

https://www.flickr.com/photos/138493...posted-public/