| In my previous article I wrote about Flood gates and | | | | Drum gates are not solid structures like the offer Flood |
| started to detail some of the different types available. I | | | | Defence systems, they are in fact hollow gate |
| mentioned Bulkhead Gates and Hinged Crest Gates. | | | | sections that are left to float on the waters surface, |
| There are other types that are used throughout the | | | | they are kept in place by being pinned to allow rotation |
| world and I will use this article to write about the | | | | down or up. They work by allowing water to enter or |
| remaining Flood Gates used today. | | | | exit the flotation chamber; this then adjusts the crest |
| Radial Gates | | | | height of the Dam. |
| These gates are in fact Rotary Gates that differ by | | | | Roller Gates |
| consisting of cylindrical sections. They have the ability | | | | These are large cylinders hoisted with a chain that lay |
| to rotate horizontally or vertically. Some of the vertical | | | | in an angled slot, the cylinders are able to move in the |
| rotating designs are called Tainter Gates; they allow | | | | slot, inside the slot the cylinders have a cogged design |
| the water to pass underneath when rotated. As a | | | | integrated and this is the mechanism that allows |
| safety feature the gate is capable f closing under its | | | | movement. |
| own weight, this is made possible by balancing the | | | | Clamshell Gates |
| hydrostatic forces by the face shape and low friction | | | | These get their name from their aesthetic design, the |
| trunnion bearings. | | | | external section is designed like a clamshell leaf. |
| Drum Gates | | | | |