Talk:Boat lift

Stats in the table

Yes, I realize that the basins of the Peterborough and Longtan locks are almost the same size, yet the reported capacities differ by a factor of 5. Perhaps the chinese lock is reporting the largest expected vessel displacement, not the displacement of the basin? Anyhow, I am going to stick with the stats I found online, even if they are questionable...

I suspect that the Three Gorges capacity is the size of the basin, not the displacement of the vessels, because some sites report its capacity as 1500 ton barges... That project seems touched by boosterism. Originally the dam was not going to have conventional locks, just a mammoth ship lift capable of lifting 10,000 ton vessels. It is not always clear whether the stats are in metric tons, long tons or short tons. -- Geo Swan 04:06, 22 February 2006 (UTC)

I just did the arithmetic. One liter of water weighs one kilogram. One cubic metre of water weighs 1,000 kilograms, a "metric ton". Using the stats for the dimensions of the Three Gorges dam the volume of the basin would be 49,000 cubic metres -- ie. 49,000 tons. I suspect that someone in China, or the person who added the stats about the three gorges basin size (that would be me) made a mistake, and put the capacity of the old-fashioned Three Gorges locks.

The volume of the Ontario basins would be 906 cubic metres, not the 1300 tons(or 1542 tons) claimed; the Longtan dam lock would be 777 cubic metres about three times the size of vessels it is said to be able to handle. The Alderton would be 312 cubic metres, 1.25 times the claimed capacity. -- Geo Swan 04:26, 22 February 2006 (UTC)

Daan Oranje 06:44, 31 December 2006 (UTC) The above would be true if the lifts were filled with water only. However, a ship floats due to the fact that it, with cargo included, is lighter than water. The actual water content is reduced with the displacement of the ship. The average weight of the lift content is therefor considerably less than calculated above and, in fact, depends on the displacement of the ship in transit, as well as the minimum waterheight required to keep the ship balanced.

LoL. Pull the other one. -- Geo Swan 05:04, 30 January 2007 (UTC)

Krasnoyarsk - boat lift or inclined plane?

The image gallery on the external link Krasnoyarsk hydroelectric dam boat lift shows that the structure is a canal inclined plane, not a boot lift. I propose to move all info regarding Krasnoyarsk to that page. K. Roose

You're right, I moved it to canal inclined plane. Markussep 15:56, 10 March 2007 (UTC)

Three Gorges Dam - boat lift or lock?

The image Image:Three gorges dam locks view from vantage point.jpg on Wikipedia Commons clearly shows that this is a lock. I propose that all references to the Gorges dam are removed from the boat lift page. K. Roose

They are locks, and also boatlifts.Jeff 21:13, 29 January 2007 (UTC)

There are locks, which are installed and working. The boat lift is still vaporware. Here's where it was supposed to go.[1]. The idea was that small passenger ships could get through faster via the boat lift, rather than going through the 5-lock chain of locks, which takes about four hours. --John Nagle (talk) 07:43, 31 August 2010 (UTC)

Last night I went looking for an update on progress on the three gorges ship lift. The most recent reference I could find was to 2008. It said construction on the ship lift had been temporarily suspended due to a recent earthquake. China is a repressive government, which can suppress bad news. I suspect that the ship lift is not just delayed, but has run into technical problems which will prevent it ever being completed. Geo Swan (talk) 02:40, 16 December 2011 (UTC)

Ambiguity in term

I have noticed the frequent use of the term Boat Lift to mean the cushion or platform for lifting boats for maintenance purposes.

I therefore feel there is a need for a disambiguation link for the term on this page.

Sidnarayan (talk) 20:55, 21 May 2008 (UTC)

Can you cite examples of this usage? Mayalld (talk) 21:09, 21 May 2008 (UTC)

282 U.S. patents have been granted for these devices! [2]--Old Moonraker (talk) 21:23, 21 May 2008 (UTC)

This is one of the many websites referring to the other (and I think more popular) use of this term.

http://boat-lift-usa.com/boat-lift-types.htm

The term Ship-Lift seems to be a better title for this page, in my opinion

Sidnarayan (talk) 13:12, 23 May 2008 (UTC)

Both Boat lift and ship lift are ambiguous, referring to devices to lift vessels out of the water, for repair work to their hulls. "Lift lock", on the other hand, is not ambiguous. It if my prefered term. Geo Swan (talk) 01:27, 10 June 2009 (UTC)

From Googling, it seems that this could be another difference in U.S. and U.K. usages: changing levels on canals in the U.K. but dry-dock applications in the U.S. The same dubious research method shows only North American usage of "lift lock", and this seems skewed by references to the famous Peterborough Lift Lock. --Old Moonraker (talk) 06:02, 10 June 2009 (UTC)

Leaving aside the reliability research methods that would help us figure out whether "ship lift" or "boat lift" are used more frequently than "lift lock", or whether the use of these terms for maintenance devices outnumber the use for transportion aren't both "ship-lift" and "boat lift" ambiguous? And isn't "lift lock" unambiguous?

I see this as an excellent reason to use "lift lock" over the other two terms. Geo Swan (talk) 08:25, 10 June 2009 (UTC)

But I don't think anyone in the UK would call the Anderton boat lift anything other than that. The term "lift lock", I would suggest, is relatively unknown on this side of the pond. EdJogg (talk) 12:15, 10 June 2009 (UTC)

As one who has visited most of the ship lifts in Europe and published a series of articles on them in the Model Engineer magazine, I have never seen the term "lock lift" in use other than in North American sources. Since the vessels on canals are normally called boats, "boat lift" would be the logical choice, but does have that confusion problem. The German examples are big enough that "ship lift" is a reasonable choice, but you may have to accept that the term is ambiguous whichever you choose.

Incidently I would not separate the vertical lifts from the inclined planes. A vertical lift might simply be regarded as a special case of an inclined plane, where the slope equals 90 degrees. I would make a distinction between devices which use caissons, devices which lift the boat from the water, and devices which move a dam and a wedge of water, although I would be interested in all of them. 202.73.198.161 (talk) 22:38, 11 June 2009 (UTC)

Ship lifts in China removed from "See also"

This link has twice been deleted, most recently on the grounds that it has only "short notes" rather than fully developed, individual articles. It's true that there's a good deal of room for expansion in the subject, but the fact that it's a bit "short" as yet doesn't seem like a good reason for denying the link. I propose reinstatement. Build the web! --Old Moonraker (talk) 12:55, 14 March 2011 (UTC)

There's already a link to the list of lifts. I don't see why any location should be singled out. Jojalozzo 13:27, 14 March 2011 (UTC)

Agreed. There is no reason for China to be singled out here. The problem is that the original link (Ship lifts in China) is a redirect, and this was replaced with the redirect target (which is generally frowned upon, per WP:MOSLINK). Now we have two links to the same page, one of them singling out a particular country's lifts.

I think the link should remain deleted until such time as Ship lifts in China is developed into a self-contained article. Alternatively, link to the other ten countries on the list page as well (only joking).

Incidentally, I've fixed the redirect to point at the correct section. -- EdJogg (talk) 13:46, 14 March 2011 (UTC)

"Duplication" is a valid point: dropping my proposal. --Old Moonraker (talk) 14:31, 14 March 2011 (UTC)

The section on "Residential boat lifts"

I proposed this article being renamed to avoid confusion like that behind the addition of this section. It is seriously off-topic in this article.

Okay, I just took a closer look at that edit, and felt comfortable reverting it.

It was added by a wiki-ID which only made that single edit, and since it is totally unreferenced, and may have been contributed by an individual in a conflict of interest. If it had referenced a single WP:Reliable source, I would have instead asked for opinions on which other article might be better places for it. Geo Swan (talk) 02:16, 15 December 2011 (UTC)

I agree with this. Residential boat "lifts" are not transportation-related. The only thing that is like them that comes close to fitting here is the motorized lifts used to take boats out of the water for maintenance and storage. At least those actually move the boat from one place to another rather than just lift it up. Jojalozzo 03:28, 15 December 2011 (UTC)

See the recent edits to Shiplift and the move proposal for both articles below.165.121.80.132 (talk) 00:53, 11 April 2013 (UTC)

Another list of ship lifts

Last night I came across a book from 1989 that had a table listing a couple of dozen shiplifts. One problem with our table is that its r eliability is questionable given that different individuals, with different interpretations, offered the figures for the lifts capacities. I think we should use the capacity figure from that table when they disagree with the figures we already have.

• Permanent International Association of Navigation Congresses. (1989). Ship lifts: report of a Study Commission within the framework of Permanent ... PIANC. ISBN 9782872230068. Retrieved 2011-12-14.

One difficulty with this table is that the authors included various kinds of inclined planes and water wedges. Another is that it had a field that described the type of the lifts in detail, but in terms I didn't understand.

I transcribed this table -- in part. I figured including the description fields would violate copyright. So left out the field that included a comment on the lift type, but I left in the fields that only contained "facts" -- as facts aren't copyrightable. My understanding of Feith v Rural is that a list of facts can be copyrightable -- based on its selective ordering of the elements. So, while the original table was in chronological order User:Geo Swan/ship lifts is ordered by the tonnage of the largest vessel the lift can carry. Geo Swan (talk) 03:01, 16 December 2011 (UTC)

Requested move

The following discussion is an archived discussion of the proposal. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section.

The result of the proposal was no consensus. I recommend WP:BRD for any users interested in renaming these articles. --BDD (talk) 21:38, 3 May 2013 (UTC)

• Boat lift → Canal boat lift
• Shiplift → Shiplift or dock boatlift

– This article has a serious name problem. The 1875 "Anderton Boat Lift" clearly has precedence, if that was the term used originally. But modern US and worldwide usage of the term is for the fixed device to store boats above the water at docks. (Question: what are the translations of the non-English names used for these products?) Previous discussion cites the 200+ patents as use of the term. I note that the Anderton device is always described using two words, and the storage device as one word.

I propose a two name changes: rename the present article to Canal boat lift, and rename Shiplift to Shiplift or Dock Boatlift. The latter article includes some mention of traveling lifts, to park multiple big ships; it should be expanded to include sling-types, and boatyard/marina cranes. A paragraph was added for pleasure craft storage-type dock boatlifts. When enough material is available about the history of those things, that could be put into its own Dock Boatlift article. If or is a no-no in a title, then I suppose portable boat lift could be renamed as Dock Boatlift for now and rewritten to include the paragraph in Shiplift and also the portable cranes which are apparently also called Boat lifts, until there is enough content about the cranes to justify an article. --Relisted. Steel1943 (talk) 03:26, 21 April 2013 (UTC) relisting see below Andrewa (talk) 21:33, 19 April 2013 (UTC) 165.121.80.132 (talk) 01:20, 11 April 2013 (UTC)

• Comment: Agree there's a problem with the current article structure and naming, but this proposal doesn't solve it IMO. Suggest we look at some alternatives. Relisting while I come up with something, and very interested in other proposals. Andrewa (talk) 21:33, 19 April 2013 (UTC)

Survey

Feel free to state your position on the renaming proposal by beginning a new line in this section with *'''Support''' or *'''Oppose''', then sign your comment with ~~~~. Since polling is not a substitute for discussion, please explain your reasons, taking into account Wikipedia's policy on article titles.

Discussion

Any additional comments:

This is how I see it...

The primary meaning of boat lift, ship lift and lift lock is the topic of this article. I think ship lift is the most used term, but that's just based on my limited personal experience at this stage. Data, anyone?

The proposed name canal boat lift doesn't really cover the topic, is confusing and a neologism.

The proposed new name Shiplift or dock boatlift is an awkward construction that doesn't in any way conform to WP:AT, and in any case the scope of that article is currently far too broad. That's the cause of the problem with finding a name for it.

We probably need three articles at least... this one, covering structures that are alternatives to canal locks, one on machines such as the Travelifts at Royal Prince Alfred Yacht Club, Port of Póvoa de Varzim#Marina, Fairwinds Marina and many other locations (see http://www.marinetravelift.com/ and I guess there are competitors), and one for the larger shipyard devices also covered by shiplift at present, see image of 250 ton trolleys.

Comments? Andrewa (talk) 22:06, 19 April 2013 (UTC)

The above discussion is preserved as an archive of the proposal. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.

Selected lifts table - unit conversions?

I added a cleanup section flag already, but if anyone knows how to make the table utilize the convert template automatically, that will be a lot easier than manually retyping all the numbers into the templates by hand!

Ninjalectual (talk) 05:59, 28 December 2018 (UTC)

Types of mechanism

I have tried to clarity differing types of mechanism for the boat lifts in the table, but am no expert. It may be helpful to have a section on this page dedicated to explaining the different types of mechanisms for a boat lift, and how they differ from each other and from locks. 176.251.175.52 (talk) 19:04, 18 June 2021 (UTC)

I've included three other inclined plains, two which use a moving gate (water slope), and one which uses a cradle (patent slip). I cannot find outside of wikipedia a good definition of a boat lift, and right now this page does not offer much in the way of a definition. I'd probably say, especially given this is a more niche technology that locks still, that a boat lift should be considered to be "any mobile apparatus for transporting boats between two differing water levels", this quite distinctly separates it from a lock which is fully stationary, and simply pumps water in/out of a closed chamber to it for achieving vertical movement.

This would lead to the inclusion of a few types

• Caisson locks
• The unsubmerged vertical caisson boat lift
• The Fulkirk wheel style rotational caisson
• Caissons on inclined planes

This may also include

• Patent slips leading to a higher body of water - Effectively these only differ from caissons on inclined planes in that they are not watertight.

And may also include

• Water slopes - These are inclined planes, but have only the gate (or end) of the mechanism move up and down. These are probably the most 'edge case' regardless of the definition used, as they definitely have less moving parts than the other mechanisms. In effect they reduce the moving caisson to just the rear water retaining wall, and then seal along the side of the rest of the channel to avoid the need for a full caisson. Given that they still avoid being heavily reliant on pumping water to change the water level, and they are a niche design, I would say they should be included under this page.

There may additionally be other mechanisms I am unaware of.176.251.175.52 (talk) 19:49, 18 June 2021 (UTC)