Is the drum of a crane a full cylinder or a hollow cylinder?

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You are way out of your league - contact a consultant -

In such designs, at minimum you have drum and sheave D/d ratios, wave breakers, motor class considerations, drum sidewall deflections and crush depths, spooling modes and fleet angle choices, lay and core and class considerations, groove size and tolerancing, (all of which go into the rope choice and drum size), gearbox types with a x3 AGMA overhauling load rating, brake considerations for autogeneration and reflected mass moment, control systems for overhauling loads, and fairly specific government regulations that must be met if you don't want to kill someobody - and that is for the drum system alone.

see OSHA and ANSI which have basic requirements for safety - but don't expect a hoist designed to their minimums to perform effciently or even at all - ones built to their requirements just kill fewer people

sorry .

oh come on... can't you smell a homework project??

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It may be, but unfortunately, I have seen way too many non-school posters trying to have NG do their engineering work, or obviously novice and overreaching posters with home projects asking for advice in a dangerous area.

And actually I did consider that maybe it was a "homework" assignment once again given by a professor 1) retained to give expert testimony who wants students to do his work 2) a prof who doesn't have a clue about the realities of the field and gives students a project that a graduate engineer with 8-10 years experience in cranes might be able to tackle under supervision

And the student will go back with some realities and ask the prof "what is _____" and get a bloank look and the education system will be just a little bit better.

I might have been a little hard, and I suppose I should support those reactionaries who think "the details" will be worked out later - since stupidity is the consultant's jam on the bread and butter - for the accident or the pile of junk..

But these days, it seems there's more than enough petty stupidity to go around

- IMHO we can leave the big dumbs in the box

The sooner the student is made aware that the ship " great idea " was wrecked in it's collision with" The Great Regulation Reef" the better. Taking on a pilot or getting a map is as important as mere seaworthiness of a vessel in completing a journey.

-- Jonathan

Barnes's theorem; for every foolproof device there is a fool greater than the proof.

To reply remove AT

One often sees hollow drums. In fact, they are mostly the norm in my experience with cranes in the shipping industry. However, there are many other considerations to be addressed. As with drive other torque transmitting devices, hollow cyliders save weight without significantly compromising strength. As others have posted, there are many specific regulations to be addressed and host of issues associated with safety. Be very careful. Consult with the Crane Manufacturers Association for more details.