Rope pumps.
Suitable for deep well use.
Low cost, simple, effective.
A series of small "cups" are fitted to an endless "rope" and
drawn up a pipe where they form adequate seals to lift the
segment of water above. While notionally you only need about
a sealing cup per head length (say 3 per rope) in practice
there are many to allow adequate sealing.

        http://www.ropepumps.org/

In resource poor environments it would be hard to compete
with such elegant devices using "high technology".
Powering is by a range of energy sources - hand, pedal,
wind, animal, motorised.

Hand powered capacities:

40 litres/minute @ 10m head
10 litres/minute @ 35m head
7 litres/minute @ 60m head (double handle).

The power (energy rate) required is related to flow BUT rope
force is affected by head as a column of water equal to well
depth is lifted at all times. Presumably well diameter drops
with head.

_________________

Russell musings:    A design which lifted "buckets" rather
than using the pipe as a seal would allow a rate related
only to speed and bucket spacing.A deep well could have
greater bucket spacing. Buckets could be added or removed
depending on pumper's strength (subject to rope strength)
and no smooth bore pipe would be needed to retain water.
Buckets would use more material volume than sealing cups but
no more than pipe. Buckets could be lower thickness than
pipe in deep wells as no hydraulic head needs to be
supported. In a deep well (say 50 metres) pipe strength
probably is an issue at the bottom.
_____________________

Numerous examples. Click on arrow below photo to see more
examples.

        http://www.ropepumps.org/English/hand.php

The cover fitted to most of the examples shown is to shade
the rope from the sun.



                Russell McMahon

______________________________

Hand Rope pumps

The "down the hole" part of a Rope pump consists of a guide
box, PVC tubes and a rope with pistons. Model A has an upper
part which consists of a wheel, a handle, and a structure or
frame to support the handle. Model P has a handle which is
mounted on poles. Materials used are angle iron, tubes and
round bar. "User made" Rope pumps are often made of wood.









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