Article Sphere Logo
 
Main Article Categories

 Alternative Medicine
 Arts And Entertainment
 Automotives
 Beauty
 Business
 Communications
 Computer And Technology
 Disease And Illness
 Finance
 Food And Beverage
 Health And Fitness
 Home And Family
 Home Based Business
 Insurance
 Internet And E-Business
 Legal
 News And Society
 Pets And Animals
 Product Reviews
 Real Estate
 Recreation And Sports
 Reference And Education
 Self Improvement
 Shopping
 Travel And Leisure
 Women Health And Fitness
 Women Interests And Issues
 Work At Home
 Writing And Speaking
 All 511 Categories
 
"Technology Reviews" Article
 Article Directory Home Product Reviews Technology Reviews

The Difference between Pulleys and Sheaves

By Expert Author: Rob Parker
View Summary | Submitted: 2007-03-27 | Word Count: 404 words | Views: 158 view(s)
Rob Parker
Pulleys have been around for a long time; they are one of the six types of simple machines, and their origins have been lost to memory. The basic concept allows loads to be lifted using much less force than would normally be applied, through a system of ropes and wheels. The term pulley is often used interchangeably with the term sheave (pronounced "shiv"); however, this usage is not technically correct. The sheave is the rotating part of the pulley system; it is the grooved wheel into which a rope fits.

A fixed pulley with a single sheave is used to change the direction in which a force is applied, but does not change the amount of force required. It is only with multiple sheaves that a pulley system offers a mechanical advantage. Each additional sheave halves the force required to move an object, but doubles the distance the rope must be pulled to achieve the same movement. Although the force exerted by the person is lessened, in the final calculation the same amount of work is done. What makes this system easier to use than raw manpower is the fact that the force needed is mitigated by the distance covered.

So, if more sheaves make the work easier, why don't we see pulley systems with umpteen sets of sheaves and miles of rope making it possible for anyone to move anything? In the real world, friction intervenes. As more sheaves and more rope come together in a system, each additional set offers a smaller and smaller advantage, until there is no gain at all. The system becomes less efficient the larger it gets.

Despite the reduction in efficiency, several sheaves are often used in tandem in one pulley system. These are known as compound pulleys in their simplest form, and block and tackle in more complex varieties. In order to increase the efficiency of the systems with multiple sheaves, the sheaves are arranged above or below each other, often with a fixed axle between them.

An effective sheave must have the minimum surface area possible for the rope or cable with which it is being used, and must also be resistant to abrasions or warping which may cause the rope to fray when the system is put into effect. When designing or discussing a block and tackle, the most important thing to remember is… not to make the common mistake of confusing pulleys and sheaves!
About the Author/Author Bio

For more information on this article or a sheave, visit BearEquipment.com

Article Source: http://www.articlesphere.com/Article/The-Difference-between-Pulleys-and-Sheaves/80860

This Article has been viewed 158 times.

Comments on this Article


More "Technology Reviews" Related Articles

 

Listed below are more articles related to the above article from the "Technology Reviews" article category.

People interested in the above article "The Difference between Pulleys and Sheaves" are also interested in the related articles listed below:

It is worth noting that companies engaged in electricity generation are also looking at these options. All in all, it will only result in the betterment of this world. Not only is the environment healthier, but you have more jobs available for everyone in the community, and better electricity options at a lower cost. For example one windmill creates at least three jobs for maintenance. This can benefit the lower classes greatly.
Do you still have a wired burglar alarm system? Well, why don’t you investigate a few wireless burglar alarmsystems Which can be bought in retail stores? Having an absence of wires and the option of additional features, these burglar alarm systems are easy to install and usage.
Most current stair lifts available in the market are made with much sophisticated parts combined with technology. The units may look complicated but they are easier to use. There are many good brands in the market. It is significant to make sure that you compare brands with the same make.
Getting a stair lift installed in one’s home is a dramatic change in once life and delivers peace of mind by knowing that the staircase does not pose any obstacle and danger in one’s life. But the search for the best and trustworthy stair lift importer to ease one’s mind from worries can be stressful itself.
Having a stair lift personally is not really a big problem especially if you have a mechanical background and you have interest for it. It can be relatively not complex for someone who really wants to add a stair lift in their house. Installing a stair lift personally can save the family a huge amount of money out of pocket. Installing also depends on the kind or unit which you have picked.
A humidifier is a household piece of equipment made to raise the level of air moisture indoors. To answer the question - How does a humidifier operate? to begin with we need to know why it is needed. In areas of the world where there are 4 seasons, the cold climate may be very uncomfortable because of the level of water vapor in the air. Humidity is a measure of the water vapor in the atmosphere.
Do you still own a wired burglar alarm system? Well, how about you read up on a few wireless burglar alarmsystems that can be found in retail stores? Having an absence of wires and the integration of additional add-ons, these burglar alarm systems provide hassle-free installation and use.
Article Directory Home Product Reviews Technology Reviews

Can't find what you're looking for? Try Google Search!
(Search in 26 languages: English, Spanish, French, Japanese, Arabic, Italian, German,
Chinese Simplified, Chinese Traditional, Dutch, Korean, Portuguese, Russian, Greek, Serbian
Slovak, Hebrew, Swedish, Romanian, Polish, Norwegian, Finnish, Danish, Czech, Croatian, Bulgarian)
 
 
Copyright © 2005 - by Larry Lim, Singapore - Article Search Engine Directory at ArticleSphere.com™
All Rights Reserved Worldwide. All Trademarks and Servicemarks are the property of the respective owners.
Template Design by Internet Marketing Singapore | Internet Marketing | Singapore Classified
Español Français Bulgarian 汉语 漢語 Croatian Czech Danish Dutch Finnish Deutsch Ελληνικά Italiano 日本語 한국어 Norwegian Polish PortRomanian Русско Serbian Slovak Swedish [أربيك] Hebrew