Talk:Crane (machine)

From Wikipedia, the free encyclopedia

Contents 1 Old Comments 2 Fabrication of a Crane 3 Truck 4 Whistle communication 5 Loader Crane 6 Famous crane operators 6.1 Paul Kenneth Vikra 7 Hammerhead Crane 8 Crane Design 9 Lewis irons? lifting tongs? 10 Wrecking Ball 11 Mechanical advantage 12 Cleanup Tags 12.1 Introduction 12.2 Restructure? 12.3 Images 12.4 Scope 12.5 History 13 New sections needed

[edit] Old Comments

Could someone add a section on how steam cranes work and where the largest ones are and what there lifting capacity is?

Could someone explain how cranes harness mechanical advantage?

A crane is a collection of simple machines, including inclined plane, wheel and axle, lever, pulley, wedge and screw. Perhaps someone will expand this article to explain how cranes work. Meanwhile, see mechanical advantage for more information. --Heron 18:31, 12 July 2005 (UTC)

[edit] Fabrication of a Crane

I work as a "Project Management" officer & I would like more about fabrication of cranes, WBS (Work Breakdown Structure) and so on.

[edit] Truck

A crane mounted in a truck to move breaked down vehicles to the garage is called a "..."?. See image http://www.gruascorsa.com.mx/gruasremolque/

What you link to could be called a "wrecker" in the US. although I think the type you link to would be a stretch to classify as a crane as there is no vertical lift involved. The "tow truck" design would probably be considered a type of mobile crane. Although I've heard the names interchanged.--J Clear 17:58, 11 June 2006 (UTC)

[edit] Whistle communication

I am sitting in my office, and there are people with cranes doing work on another building, but they seem to be using whistles (like sport referees' whistles) to communicate. Could someone investigate that?

I Googled on "whistle coummnication crane", then on "whistle hoist". Here is what appears to be a California statue on hand-, electrical-, and audiable-hoist signals:
http://www.dir.ca.gov/title8/1605_21.html
Subchapter 4. Construction Safety Orders
Article 14. Construction Hoists
§1605.21. Introduction.

"(c) Audible Signals.

Audible signals shall not be used when there are surrounding noises of the same, or nearly the same, frequency and octave level. Signals given by means of a whistle, bell, horn, or other audible means are as follows:

(1) Hoist: Two short blasts or gongs.

(2) Lower: Three short blasts or gongs.

(3) Slow: Four long blasts or gongs.

(4) Stop: One short blast or gong.

(5) Emergency Stop: Series of short blasts or gongs.

(6) Dog Off Load: One long blast or gong. "

While you're next to the scene, you're asking us to Google? The virtual world is catching up way too fast for me. BoH 01:00, 31 August 2006 (UTC)

That is interesting way to signal the operator. Don't know if I would like that. I operate a TM9100 Grove(100 ton) here in Hutch, KS. Alot of times at the salt mines and elevators I am unable to see what I'm hoisting so we use radios. The whistles would, IMO, take a lot to get used to. And if you can see your load and those you're working for, nothing beats hand signals. I would be interested to hear from operators that use or have used the whistle method.RaiderfanaticDennis RyanRaiderfanatic

[edit] Loader Crane

Almost invariably called a "Hiab" by its' operators, this is a hydraulically-powered articulated arm fitted to a trailer, used to move goods onto or off of the trailer.

Perhaps this is true in Europe, but I am unfamiliar with the term in the United States.

Never heard of that either, and I live in Denmark and work in a company with several loader crane trucks... By the way, cranes from Palfinger, Fassi and 3-4 other names that I don't remember are quite common in DK, so maybe Hiab and HMF shouldn't stand alone as examples? G®iffen 16:00, 28 September 2006 (UTC)

In the UK they are generally referred to as 'Hiabs', and not just by operators. I have revised the paragraph to suit, although the reasoning might be a bit weasly for some. EdJogg 18:24, 20 March 2007 (UTC)

[edit] Famous crane operators

[edit] Paul Kenneth Vikra

"The very first crane operator ( North sea) who actually managed to put an stand by vessel on pipedeck. During this incident the only casulty was an unfortunate seagal. " moved from article by: Gregorydavid 14:34, 27 May 2006 (UTC)

[edit] Hammerhead Crane

Hammerhead or Giant Cantilever Crane. Good PD photo here. Is this worth it's own section or is it a sub type of the tower crane? It seems to predate the tower crane. Perhaps both hammerhead and tower are types of Cantilever. Anyway I'm far from a crane expert/historian, so I'll leave it to those to sort out. There is an unlinked mention of one in Philadelphia Naval Shipyard that ought to link here.--J Clear 17:48, 11 June 2006 (UTC)

It is an amazing photo showing what appears to be a number of heavy artillery barrels being lifted simultaneously. It looks like an extreme heavy duty tower crane with horisontal boom and crawler with large counter weight mounted on large tower with slewing beaings. Gregorydavid 18:15, 16 August 2006 (UTC)

[edit] Crane Design

I am interested in detailed engineering design of plate box girder used as a crane girder.

=Rajendra Sawant, email : rajsawant@mtnl.net.in

Please include the statics involved in the cranes design.

[edit] Lewis irons? lifting tongs?

The terms lewis irons and lifting tongs are used in the article, but I could not find any explanation for what these are. 「ѕʀʟ·✎」

see Chain-linked Lewis

Gregorydavid 15:26, 19 November 2006 (UTC)

Thanks! Also thanks for fixing the link in the article. Note that the terms "lewis irons" doesn't appear in the Chain-linked Lewis article, should it? Should it link back to Crane (machine)? 「ѕʀʟ·✎」

The Lewis irons are actually a specialised device which sometimes takes the place of a hook when the lifting of heavy stone is undertaken. The Lewis irons also facilitate the placing of a heavy cut stone into its final position without any slings getting trapped under the stone. Gregorydavid 07:27, 7 January 2007 (UTC)

[edit] Wrecking Ball

Should this be added to the list. I know they are not used, but it is still a crane. Is it? Thanks, CarpD 11/25/06

[edit] Mechanical advantage

The text states:

The lever. A balance crane contains a horizontal beam (the lever) pivoted about a point called the fulcrum. The principle of the lever allows a heavy load attached to the shorter end of the beam to be lifted by a smaller force applied in the opposite direction to the longer end of the beam. The ratio of the load's weight to the applied force is equal to the ratio of the lengths of the longer arm and the shorter arm, and is called the mechanical advantage.

While the principle of leverage is correct, its application in the modern balance crane is not. The short end of the crane is where the counterweight is located, and the load is lifted by the long end. The mechanical advantage of leverage would go to the load.

I agree. The article doesn't mention any crane type that has the load attached to a shorter arm and force applied to a longer arm. The "lever" list item under "Mechanical principles" thus seems misleading. I also think this problem is what the first poster above ("Could someone explain how cranes harness mechanical advantage?") was referring to. - Mglg 23:02, 4 June 2006 (UTC)

The counterweight at the short end of the beam is to help balance the crane as a whole.

Each crane has a load diagram that indicates what load can be lifted. In the case of a crane with a long horisontal beam the permissible load decreases with increasing distance of the hook from the tower. The actually lifting capacity of the crane motor and gear train is where the mechanical advantage comes in. The force in the cable at the hook is very high, but the force in the cable on the pulley that the motor feels is low. The machanical advantage is that the weak motor can pick up the load on the hook. To do this the pulley on the motor has to pull a realtively long piece of cable while the load just lifts off the ground. Gregorydavid 06:58, 5 June 2006 (UTC)

Yes of course. But here we are talking about the entry "the lever", and specifically the statement that "The principle of the lever allows a heavy load attached to the shorter end of the beam to be lifted by a smaller force applied in the opposite direction to the longer end of the beam." This function of levers, while true, does not seem to apply to any part of a crane, and the "lever" entry should therefore be removed from the article. --mglg_(talk) 20:10, 30 August 2006 (UTC)

I added this image which has subsequently been removed:

Elementary manual crane at well near Tiruchendur.

My caption clearly states that this is a type of elementary crane. The crane utilises the principal of the lever and is designed to enable one or more human beings to lift a bucket of water from a well. The lever is cleverly balanced so that it returns to the ready position when the bucket is empty. The sheaves, and winding drums were introduced some time later.. Gregorydavid 07:06, 7 January 2007 (UTC)

That waterlifting device looks not like a crane, but a shaduf. Gun Powder Ma 22:54, 7 January 2007 (UTC)

Thanks for the link. Yes, it is exactly like a shadoof. Only with a crane some of the components and functionality have been developed and mechanised further..Gregorydavid 07:53, 9 January 2007 (UTC)

[edit] Cleanup Tags

I have already done a quantity of tidying work, but it needs much more help yet.

EdJogg 18:22, 20 March 2007 (UTC)

[edit] Introduction

The introduction contains a long list of crane types in an inappropriate style – this needs removing to the 'crane types' section, and serious copy-editing! Having removed it, the introduction will require a re-write, addressing:

• definition of a crane – which I think is fundamentally a hoist that can move the load laterally
• inclusion of history
• includion of 'how it works'
• simplification of crane types covered
• etc

Essentially, the lead paragraph should provide a summary of the article for anyone who doesn't have the time to read the rest.

EdJogg 18:22, 20 March 2007 (UTC)

Done. I'm sure it will need polishing by someone else, but at least it now covers the following article with sufficient information to exist as a stand-alone section.

The following 'paragraph' was removed as 'unredeemable'. There is content within that is not otherwise covered in the article, but the lead paragraph is not the place for it, and certainly not in this form!

Construction cranes have either telescoping, lattice or articulating booms. Telescoping boom cranes include the Industrial, Rough Terrain, Truck Mounted, All Terrain and City Cranes. Lattice boom cranes include the Crawler Mounted, Truck Mounted, Ringer Mounted and Hammerhead and Luffing Boom tower cranes. Articulating boom cranes are mounted on commercial trucks and can have telescoping boom sections and hoists. Railroad Track and Floating Cranes can be either telescoping, lattice or articulating boom. Manufacturing cranes include the Mono-Rails, Bridge, Polar, Gantry and Stacker Cranes.

EdJogg 12:50, 27 March 2007 (UTC)

[edit] Restructure?

I think the main sections are in an inappropriate order. The 'how a crane works' section should come first, followed by the history, followed by the types, with the other sections following behind.

Done – at least, I've had a go at it!

EdJogg 13:55, 27 March 2007 (UTC)

The 'types' section needs re-ordering. Not sure how. Various ways of listing:

• Alphabetical - not really very helpful
• By frequency? - most common types first?
• Chronologically? - earliest form first (this would be a challenge!)
• By size? - smallest cranes first (loader cranes?) right up to the floating ones?
• By paragraph length? - this could work, since the more 'interesting' types will have more scope for descriptive prose

In all cases the aim should be to create a summary that could (potentially) lead to a Main Article. (This would appear to be the case with crane vessel, although whether this is exactly the same as a floating crane is another matter...)

EdJogg 18:22, 20 March 2007 (UTC)

[edit] Images

Several types of crane – notably the various mobile varieties – do not have photos, yet there are a whole raft of tower crane pictures. Would be better to have thumbnails of each type, with a gallery for the details of the tower cranes.

EdJogg 18:22, 20 March 2007 (UTC)

[edit] Scope

Many of the sections only discuss current practice, for example, remote controls on Hiabs have not been around that long, and I suspect that there are many that still do not have such facility. I have addressed a couple of these areas, but I am no crane expert!

EdJogg 18:22, 20 March 2007 (UTC)

[edit] History

Stops at 1340!!! Much more work needed here!

• Who built the first iron crane?
• Who built the first steam crane?
• Who invented the tower crane?
• When did wire rope take over from 'rope' rope?
• When were hydraulics first introduced?
• etc

EdJogg 13:06, 27 March 2007 (UTC)

[edit] New sections needed

In addition to the above cleanup suggestions, I think the following extra information could be usefully provided here. The sections should exist near the top of the article to assist readers understand what follows (and allow slightly more technical language further down).

• Crane components

  Brief description (with link where appropriate) of the essential and optional parts of a crane: jib/boom, winch, pulleys, rope/cable, gantry, tower, etc. Could also encompass lattice booms, telescopic booms, etc

• Crane terminology

  Not being a crane expert I cannot add much here, but the terms 'luff', 'hoist' and 'slew' have specific meanings, I believe, and I'm sure there are others

EdJogg 13:06, 27 March 2007 (UTC)