A view of the cranes, with legs running on rails eitehr side of a railway line and showing the flat-topped arch above.
Rename. These aren't "portal cranes". I don't know if the original creator was aware that "portal" isn't the adjective form of "port"? Andy Dingley (talk) 09:16, 1 June 2015 (UTC)[reply]
Sorry Andy, but 'portal' here means having doorway-like features. They are described as portal cranes in English Wikipedia: Stothert & Pitt#Electric dock cranes.
According to the Commons Category:Portal cranes they ... are a form of crane where a large rectangular framework forms a flat-topped arch with a gantry across the top. This whole portal frame can move in one direction by a railway truck under each end. These cranes have four legs which end in rail bogies (American English: 'trucks') which allow them to move along the dockside. Between the legs they straddle a railway line. As they only span a single track the cranes themselves only rotate; they do not need to traverse across several tracks as is seen on larger portal cranes. Geof Sheppard (talk) 12:55, 1 June 2015 (UTC)[reply]
I hope this doesn't come as a shock, but WP isn't a RS for definitions. That article can't even get the number of cranes right!
These are not portal cranes. Yes, a portal crane straddles something and may move (not all portal cranes move, but most do). However it's inherent in the portal crane concept that they can lift the things they're straddling. The Stothert & Pitt cranes in Bristol are jib cranes: they can't lift something directly beneath them. They are not portal cranes. Here's an illustration of the sort of designs that are portal cranes. http://www.konecranesusa.com/equipment/portal-cranesAndy Dingley (talk) 16:19, 1 June 2015 (UTC)[reply]
You're right, Wikipedia isn't perfect when it comes to definitions so let's look outside:
The United States Department of Labor defines them as having a rotating upperstructure, hoist machinery, and boom mounted on top of a structural gantry which may ... have travel capability. The gantry legs or columns usually ... allow passage of traffic beneath the gantry.
Yo-Pi Port Machinery are offering for sale several modern equivalents which they describe as portal cranes.
So there are several reasons for describing them as I have. What are you proposing the category be renamed as? Geof Sheppard (talk)
