Need Help Selecting a Motor Type

That's it? That's all the information you're going to give us. A (one and only one) drum (of steel, titanium, hollow, solid) will spin with ropes (two or more made of sisal, nylon, woven spider silk) to lift a 3000 tonne ship somewhere near or around the massive three gorge dam.

I will gladly help students that demonstrate an effort in doing their homework. You have not demonstrated any knowledge or effort on your part to solve this problem. I cannot help anyone that doesn't understand the question, let alone an answer.

I'm surprised Wu Wu figured that out so quickly.

I fixed those that I could.

If the truth hurts, maybe it should!

They learned it from management.

Damn those engineers for being such clever and observative bunch.

I'd go with a really, really big blue electric one.

Better yet, make that a humongous, orange electric one, with big wires.

Talk to a motor supplier. They need a good laugh too.

Of course it's not nearly so simple, you must first have a design for the lift that will define the needed motor sizes, because there will be several motors needed...The weight will need to be counter balanced to make it more efficient, you will need many pulleys and ropes...Here are some details on the current design being used...

http://probeinternational.org/library/wp-content/uploads/2011/01/Ship-lift-at-Three-Gorges-Dam-China-design-of-steel-structures.pdf

http://www.altramotion.com/newsroom/2016/03/ap-svendborg-bsfi-braking-systems-for-dam-ship-lift

Thanks for that. I see they went with really, really big blue electric motors in their final design.

That should help the student with his motor"design".

<Beaming up now>

A Saturn V rocket engine sounds about right.

Might a system of locks have been considered as an alternative?

They have a lock system as well....The lift is much faster though...Think of it as the HOV lane of river travel....

One possibility would be a constant-torque variable frequency drive with matched motor. A mechanical alternative would be to include a centrifugal clutch or torque converter in the drive train.

Well I think an alternative drive would be direct drive from a Pelton wheel that would be driven hydraulically coupled to a geared lift with a shift capability from up to down...but that probably would have to be part of the original design...after the fact you have to go with what works...

I seriously doubt that for a number of reasons, one being that this sort of question is handled by paid Engineering firms employing consultancy companies, the other being construction of the three gorge dam's ship lift was completed in January 2016 by Lahmeyer.

Three_Gorges_Dam

If this is a school project or general interest try performing some research into the dam itself and those like Lahmeyer who were involved in the ship lift design.

If you meant that you are working on something SIMILAR to the Three Gorges Dam lift, why are you asking us?

The motor power is the rate of change of potential energy divided by the system efficiency. Since there is nothing in the original post about speed, it is not possible to size the motor.

• It is perfectly possible to use the power of falling water to provide the lift, thereby not needing a motor at all. That is how locks work on a canal. The technology is over 200 years old, i.e. predating the electric motor era.

The best type of motor for your purpose would be:

#1: American Made

#2: Capable of handling the torque required

#3: Capable of providing the speed required

A: a small appliance clock motor will lift the ship if gearing is sufficient,and time is not a factor.

#4:Capable of the duty cycle required

#5:Capable of surviving the environment in which it will operate

#6 Capable of using the available power to the site.

A: Remember,if the motor is too large you may overload the generators at the site,resulting in a catastrophic failure of the entire electrical grid.

Simple solutions for a simple problem,as described.

Here is a motor/gear combination that is EXACTLY what you need:

Lots of torque,but slow......

http://sploid.gizmodo.com/this-mind-bending-machine-completes-one-turn-every-2-3-1457516789

In a couple of centuries, it should have the backlash out.

Sooooo.. How much HP to lift a 3000 tonne ship in 2.3 trillion years? I was planning on using 2 AAA batteries. What type of Battery will last 2.3 trillion years. OOOPS! Forgot to get lift height. I'll get back with you on that in 1000 years or so. I will be on coffee break for a couple of centuries. -- JHF

OOPS! I forgot to include this automatic transmission option:

https://www.bing.com/videos/search?q=turbo+encabulator+video&view=detail&mid=20FF25DFA9B4CC3B53D220FF25DFA9B4CC3B53D2&FORM=VIRE

Is the water over your head? It seems that this project is. -- JHF

"Designing" a motor is best left to the electric motor manufacturers, unless of course you happen to work for one of them, and then the information should be readily available. If you are needed to "specify" and electric motor, contact the manufacturer and they can supply you with a catalogue or a link on line.

However, as suggested elsewhere in this thread, you are missing an awful lot of other details to complete the selection.

Why design anything. The draw works from a drilling rig.

http://www.drillingformulas.com/block-and-drilling-line-calculation/