# Electronic Components/Crane Construction.

Question

Crane Design
QUESTION: Dear Deirdre

http://en.wikipedia.org/wiki/Crane_(machine)

Cranes are designed to lift and move specific loads capacity in tons. What are the input parameters in terms of mechanical, electronic, electrical components considered for Crane Construction
in terms of its ability to lift more loads ?

i.e. Electrical Power, Pulleys, Shafts, Ropes, Levers, Crane Height etc.

Example :

Some Cranes can lift a load of 100 ton, while some cranes can lift say a load of 500 ton. So in the second case, what are the parameters considered for designing the crane which can lift more loads.

Thanks & Regards,
Prashant S Akerkar

ANSWER: The amount of load which a crane can lift is far less dependent on total power, and much more related to physical stability, counterbalance, etc.
Power will help determine how quickly a load may be lifted - with less power, it can take quite some time to move a significant amount of weight very fast. But consider that you could lift a freight ship with an eye-dropper or a thimble just by adding water to a dry-dock.

Also, the amount of weight a crane can lift is dependent on the angle at which that load is to be lifted. A crane can lift heavier loads closer to the body of the crane, than if it needs to reach out to do the lifting. This is very similar to a fire-truck ladder. As the ladder is closer to vertical, it can handle a greater load. It's more about stability and balance than power.

Now if you want to move a heavy load quickly, that comes down to a simple equation - Force = Mass * Acceleration. The heavier the load, and the quicker you need to move it, the more force you will need to apply.

---------- FOLLOW-UP ----------

QUESTION: Dear Deirdre

Thank you.

http://en.wikipedia.org/wiki/Hydraulic_cylinder
http://en.wikipedia.org/wiki/Hydraulic_motor

Hydraulic Cylinder Design could be one of the important factors for lifting more load in Crane Construction ?

Thanks & Regards,
Prashant S Akerkar

The design of a hydraulic cylinder is one factor in the design. Basically a hydraulic cylinder is a piston. The circular area of the surface of a piston, coupled with the pressure of the hydraulic fluid determines the amount of pressure that the piston can exert. For example, with a radius of 1", the surface area would be about 3.14 " ^2 (Pi * radius squared). If the hydraulic pressure is 1,000 lbs, then the force exerted by that piston would be 3,140 lbs (approx). A 2" cylinder would increase this to about 12,560 lbs. and a 4" cylinder to more than 50,000 lbs. And some hydraulic power units are capable of pressures much greater than 1,000 lbs - some going up to 15,000 lbs or more.

Of course, the cylinder must be able to withstand these forces - while there are 50,000 lbs of force on the piston, the body of the cylinder, as well as the hoses, etc. need to withstand these tremendous pressures.

And while pressure is important, so is flow rate. You might have something capable of exerting 50,000 lbs, but the rate of movement will depend entirely on how quickly that fluid can be delivered.

Lastly, in designing such a system (one of the images you posted was an excavator) it is important to understand the physics of levers. Using mechanical advantage of a lever can help you take full advantage of the power that the hydraulic cylinder can deliver.
Questioner's Rating
 Rating(1-10) Knowledgeability = 10 Clarity of Response = 10 Politeness = 10 Comment Dear Deirdre Thank you. Thanks & Regards, Prashant S Akerkar

Electronic Components

Volunteer

#### Deirdre Hebert

##### Expertise

I can answer most questions regarding electronic components, what they are and how to use them.

##### Experience

I worked for a number of years in the electronic component testing industry, designing and building automated test equipment for the electronic manufacturing industry.

Publications
Numerous technical manuals for the equipment we built.

Education/Credentials
UNH, CCAF and others

Past/Present Clients
General Electric, Motorola, Ford, Sensonor and others.