Hand Pumps Hand Pumps2 Hand Pumps3 Hand Pumps4

Hand Pumps

Because water is one of the basic necessities of life, we need it in order to survive. For a long time now, man has been working tirelessly on the ways he could make water available for his use at any one time. The movement of water from one position to the other in necessary in some cases before it could be made available for use. Water is however one of the many types of liquid that need to be moved from places.

Hand pumps were designed to help with the movements of fluids through the use of human power and mechanical advantage. It is the combination of these two that move air or fluids from one place to another. In different countries all over the world, these pumps are being used for different marine, industrial, leisure and irrigation purposes.

Wherever fluids generally are being pumped, suction and lift are very important and worthy of consideration. The vertical distance between the center of the pump and itself the fluid that is to be pumped is known as the suction. The lift is calculated as the vertical distance between the delivery point and the pump. It is on this general principle that hand pumps work.

Their functionality is limited by the atmospheric pressure prevailing at the moment of operation to a depth of less than 7 meters. A number of factors determine the height to which these pumps can lift fluids. The design and the ability of the pump as well as that of the operator are factors that lift the weight in the delivery pipe and determine the height the fluid would reach.

It is therefore possible to realize different results from the same pump when used by different people. When an operator uses the same pump, he would also be able to achieve a greater lift if a smaller diameter pipe was used when compared with a pipe with a larger diameter. Hand pumps occur in different types but majorly, they all operate on a piston and diaphragm or rotary vane principle that has a check valve on the entry as well as the exit ports to the chamber that operates in opposite directions. However it is very usual to see these pumps with plungers or reciprocating pistons which are positive displacements.

It was discovered a long time ago that water would always find its lowest level and seek to maintain it. It is this principle that many simple hand pumps use in the emptying of water or fuel from one container into another. Once the container placed at a higher level is full, fluid would flow from it effortlessly into the lower container. Most of these pumps would allow fluid through them in the direction of the flow and notable of such pumps is the diaphragm pump. It is therefore possible that even with large volumes of water or any liquid like the swimming pool, the container or space holding the fluid can be emptied using very little energy or effort.

The kind of hand pumps known as the direct action pumps have pumping rods that are moved up and down by the user directly in order to discharge water. These pumps are very easy to install and maintain in comparison to other types of pumps. They are however limited by the maximum column of water a person can lift physically which is about a height of 15 meters. It would be possible to lift water for a distance more than 15 meters when deep well pumps are used.

It would however humanly impossible to lift this kind of weight of this column of water directly. If a form of mechanical advantage system like what is seen in a flywheel or lever is used, it would then be possible. Since this type of pumps would be used to carry weightier loads, they need to be constructed to be strong and sturdy enough so as to be able to manage the extra stresses.

There seems to be more complication in the installation and maintenance of this pump type when compared with other types of hand pumps. There is no limitation theoretically to the extraction of water when a deep well pump is used. The depth however poses a limitation to physical human power in lifting water through its column of water which is about 80 meters.

The diaphragm pump is another type of pump and this pump has the advantage of being able to pump water relatively lightly because it lacks the pulling rod and generally the pump is corrosion resistant. Just as you might have guessed, this pump type also has a disadvantage. The diaphragm pump requires the use of a specific length of tubing and the use of high quality rubber diaphragms.

These materials are costly and they are considered relatively inefficient because of the extra work that need be done to deform the diaphragm. Rubber diaphragms eventually grow weak and start leaking after some time. Where these pumps are use instead of other types of hand pumps, they are often abandoned when replacement is not provided for the rubber diaphragms.