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Description

A pulley to ease irrigation of one's garden, its manufacture and sale is part of the local rural economy. It should be light weight, smoothly running and easy to repair.


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Pulley
<< Back to category Water & Sanitation

Ready for testing in practice Fivefold reduction of cost Applicable within poverty Nutricion Comfort Rural



Why
The use of a pulley to lift water from a well is a great improvement over having to lift a bucket with water on a rope with your arms stretched out in front of you (see picture, Burina Faso, 1977). In The Gambia we found farms and gardens given up, because the water table had sunken too deep. To lift water from these wells in sufficient quantity to water the garden had become too heavy a task.
As the pulley can not always be left at the site of the well to prevent theft, such a pulley should be light in weight as to make it easy to take it home. It should be robust, take rough handling such as smashing it against a wall or the floor. It should run accurate with little friction. As indispensable for productive working, it should be easy to repair, even during use in the field.

How
The construction of the pulley is meant to be appropriate for manufacture in a village.

  • The rim of a pulley can be cut from of thrown car tires.
  • The hub is made of wood and not from steel to promote manufacture in village handicraft.
  • A method of construction is developed that needs no fasteners. All composing parts stay together because of being mounted with pretension.
  • An easily applicable method takes care for cutting the spokes to the accurate size that ascertains running without any wobbling.
  • The bearing of the pulley consists of two steel pins driven into the center of the wooden hub, running into some windings of rope, attached to the supporting frame construction. Because the pin has a small diameter and because of steel and plastic match well as bearing materials, the pulley runs very smooth and light.
  • Any wear in this bearing is simply repaired by winding a little more rope from the frame around the bearing pins of the pulley.

    The development of this method of pulley construction and manufacture is done in cooperation with a rural project in Senegal, managed by the Foundation "Keur Mousse".The picture shows the first prototype made together with Ives Faye.
    Reports on progress in its construction can be found below. A provisional construction manual is put together from pictures as available at present.



  • Additional information



    Planned progress

  • Put together the construction manuals out of earlier 'News' publications.
  • Test the pulley and its supporting constuction for two levels of use. One is the lifting of water (=20kg), the other lifting of a person out of a well (=with margin for safety 200kg)
  • Test the supporting construction over the well for loads up to 200 kg.
  • Field test in Sengal. Local construction in Keur Mousse as well from wooden sticks as from steel tubes.



  • Internal links



    External Links

    Links related to use and construction of a pulley

    • Licence offered on Indian design for a pulley with stop
      Background info on the importance of a properly working pulley, info on numbers re. use of the pulley.
      http://www.sristi.org/pulley_tech.html
    • Send us an email form about any relevant link, that should be added here


    What other people say...

    If you like you can add your own comment

    by Hans Baarslag - Wed Dec 01 (2004)
    Pulley
    Dear Sir Your pulley as a method for hauling waterfrom (deep) wells looks very good will not rust and is easy to repair The materials can be found every where in developping countries But one thing wouldn,t t be helpful to have a ratchet mechanism also on the pulley.In that way you can stop and rest half way or you will not burn your hands when the water is running down and you must try and stop it. greeting Hans Baarslag

    by Reinder / Demotech - Wed Dec 01 (2004)
    Re: Pulley
    Mr. Hans! You confuse two ways of lifting water from a well: - Using a drum on which a rope can be wound. This drum is driven by a crank. This system employs a bigger bucket or container than the next item. Indeed such a water lifting device needs a racket mechanism, specially to be able to fetch and empty the bucket when it is within grip. - Using a pulley as is illustrated in the two top pictures to be found at www.demotech.org/presentation.php?p=6 uses a smaller container of rubber bag. To haul water depends on swift movements, the bags 'flies' up and is thrown down again. Same with the pulley system as now being developed for the Senegal project. The effectiveness of this system depends on large and swift body movements of arms, shoulders and back of able people. It is not meant for children or older people. Here again the rubber bag containing only about 7 liters, is pulled up fast, when reaching the top, the operator stop pulling and grips the bag in mid air when it stops in front of him. As this movement is repeated for hours, such movements become very accurate and effective. It may be clear that any added racket construction would be superfluous.

    by Marc - Wed Dec 02 (2009)

    by Sunem - Sat Dec 03 (2005)
    Re: Pulley
    You have a very good information and you need a cordial congratulations of my part, because with your help, maby I ?m going to have a10 in my expedient and a 10 in my homework. THANKYOU FOR YOUR HELP

    by subramani nair - Tue Dec 05 (2006)
    well pulley
    dear sir/madam i would like to make a well pulley & lift pulley for my niece for her school project, pls advice/guide me through how to make with less cost & with craft items i.e like cardboard/cardpaper stick etc. suggest u to add this childrens site also pls reply urgently regards s.nair

    If you like you can add your own comment



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