One kind of positive displacement pump that is operated by humans is the hand pump. In many rural regions without piped water hookups, they are a regular sight. Hand pumps are widely used all over the world because of their straightforward, sturdy construction, low maintenance needs, and ease of use.
It was in Europe in the 1400s that the hand-operated piston pump was created. Through the use of a hand pump or ordinary water source, a large number of villages, towns, and cities were able to get a consistent supply of water during the ensuing centuries.
Hand pumps were typically constructed on pre-existing water wells; therefore, their use is more of an upgrade to current infrastructure than a whole new type of infrastructure.
Well, in this reading, we explore what a hand pump is, its applications, diagram, types, and how it works. We also discussed its advantages.
Let’s get started!
What Is A Hand Pump?
Hand pumps are manually operated pumps that transport fluids or air from one location to another by using mechanical advantages and human strength. Every nation in the world uses them for a broad range of recreational, agricultural, maritime, and industrial purposes.
Many types of hand pumps have a check valve at the chamber’s input and outlet holes that operates in opposing directions. These pumps mostly work on a piston, diaphragm, or rotary valve basis. The majority of hand pumps are positive displacement pumps that are either plunger or piston pumps.
Hand pumps, which may be put in hand-dug wells or boreholes, are frequently utilized in poor nations for both private and municipal water delivery.
Hand pumps are devices that are manually operated as opposed to making use of air or electricity. Hand pumps come in two different types: centrifugal and positive displacement, which use twin diaphragms or pistons.
Displacement that is positive Both single- and double-acting hand pumps are possible. Single-acting pumps only work in one direction; that is, they suck fluid in when the lever is moved up or advanced and release it when it is pushed down or lowered.
Application Of A Hand Pump
- Widely used in rural areas for drinking groundwater.
- Used for shear-sensitive fruits and vegetables.
- Used in agriculture for transferring sludge and slurry.
- Used for oil pumping (lubricating and non-lubricating).
- Used for varnish and paints.
- Used for lotions, creams, and cosmetics.
- Used for aeration, pond filtering, and water pumping from wells.
- A piston or plunger, a lever fastened to a moving point, a connecting rod, and a washer enable the manual water pump to function.
Diagram Of A Hand Pump
Types Of Hand Pumps
Below are the various types of hand pumps:
- Progressive cavity.
- Diaphragm.
- Deep wells.
- Direct action.
- Chain pump.
- Siphon.
- Force Pump.
- Suction and lift hand pumps.
Progressive cavity
Another kind of positive displacement pump is a progressive cavity pump. Despite its tiny size, this pump is shown to be more efficient. The pumps have a double-helical stator with a helical rotor within. The cavity fills with water as soon as the rotor rotates, and it is finally pushed out.
Its usual gear mechanism technology and small design make it extremely difficult for an expert in the area to maintain or repair. This also raises the cost of the pump because it is discovered to have a conventional mechanism. When looking at a basic progressive cavity pump example, a rope and washer pump can be one of them.
Diaphragm
Diaphragm pumps have the benefit of being corrosion-resistant and relatively easy to pump because they don’t require tie rods. Their drawback is that they need premium rubber diaphragms and a certain length of tubing, which are costly and inefficient because of the extra work needed to deform the diaphragm.
Rubber diaphragms need to be changed since they ultimately leak. When the diaphragms wear out, diaphragm pumps in impoverished rural regions are frequently abandoned since this is usually difficult and costly.
Deep wells
Anywhere that water needs to be raised from a deep source, deep well hand pumps are used. These pumps are used at depths of more than 15 meters. The weight of the water that has to be raised by deep well hand pumps is too heavy for a human to handle.
To make the job easier in these situations, mechanical elements like a flywheel or lever are employed. Additional information on the setup and upkeep of deep good hand pumps is provided below:
Compared to other hand pumps, it is more costly and intricate. Because of the nature of the labour required, these are the kind of pumps that are proven to be stronger.
There are no restrictions on the depth at which a deep well hand pump may function. It is practically constrained by human strength. Generally speaking, deep well hand pumps have an operational depth of 80 meters.
Direct action
Direct action hand pumps release water by having the operator move the pumping rod up and down. Although direct action handpumps are simple to install and operate, they can only move a maximum of 15 meters of water at a time. The EMAS pump and the can zed pump are two types of direct-action pumps.
Chain pump
A chain pump is composed of an endless chain holding a succession of discs that drop into the water and then climb within a tube, taking with them a big quantity of water. They are a simply manufactured, old hand-powered pumping technology in the 18th century they were employed as ship’s bilge pumps.
Siphon
A bent pipe is the most basic type of syphon. In order for the water to flow, one side of this manual water pump must be placed in water; the other side must be submerged in a reservoir or water tank in order to draw water into the pump.
For this pump, the receiving water tank’s height should be lower than the supplying vessel’s height. Water always moves from the upper head area to the lower head area as a result.
According to this theory, the gasoline or water tank is poured into the lower head tank using a basic pump that has a rubber or plastic bulb and flap valves on both ends. The liquid flows smoothly from the upper tank to the lower tank when the bulb is filled.
The primary benefits of a syphon are its ability to operate in a vacuum and at a height higher than the fluid’s hydraulic pressure.
Force Pump
A pressure pump can be used if the water has to be raised to a height of approximately 7 meters, above which a suction or lift pump can function well, or if the pressure needs to be increased so that the water leaves a nozzle with a powerful force, such through a fire hose.
In its manual version, it depends on a person to pump a handle, just as a suction pump. The distinction is that the water leaves through a pipe or nozzle on the side of the master cylinder after being drawn through the lower valve (by raising the piston that is linked to the handle).
When the piston or plunger is driven down again on the subsequent stroke, the water that was drawn in via the lower valve and trapped there is pressed down once again.
Suction and lift hand pumps
Two crucial functions of the pumping fluid are sucking and raising. Lift is the vertical distance between the delivery point and the pump, whereas suction is the vertical distance between the center of the pump and the liquid to be raised.
The hand water pump’s operating depth is less than 7 meters, and its suction depth is controlled by air pressure.
The ability of the pump and the operator to raise the weight in the supply line determines whether the pump can be lifted. As a result, smaller hoses allow the same operator and pump to accomplish a greater stroke than bigger hoses.
Benefits of Lift and Suction Pumps:
Electricity is not required.
These pumps are very dependable.
With fewer tubes, these pumps can raise a lot of water.
How Does Hand Pump Work?
Raising the lever causes the piston to descend, allowing water to flow via the tubes or holes and raising the washer due to the water pressure. In essence, a suction action is produced.
The washer performs the same thing when the lever is lowered, stopping the water flow and allowing the water to collect in the pump.
The quantity of water that gathers and eventually flows out of the exit valve rises with repeated execution of the procedure.
The manual water pump may be employed in the industrial sector because of its safe and easy operation, which allows for adequate suction of chemicals, as well as in the home to pump modest volumes of liquid from a shallow well or barrel.
Prior to pumping the process fluid, positive displacement pumps need to be primed. Removing air from the system to make room for the process fluid to flow is known as “priming.” A well-hand pump is one that removes air from the system and replaces it with water.
Pressing the pump lever downward draws water into the cylinder. The piston rises and the foot valve opens when the pump lever is pressed downward; the piston non-return valve closes as the piston rises.
The operator raises the pump lever when the piston reaches its maximum transit point. The piston goes downward and the foot valve closes when the pump lever is pulled upward; the piston non-return valve remains open during this movement. Water is transferred from the piston non-return valve’s underside to its topside as a result of this movement. The water that is presently on its topside is likewise moved upward as the piston goes higher again.
When the hand pump lever is repeatedly pushed and pulled, more liquid is sucked into the cylinder, raising the water level inside it. The water starts to flow out of the pump when the water level increases and reaches the height of the discharge pipe.
Advantages Of Hand Pumps
- Easy installation.
- High efficiency and versatility.
- Highly resistant to mechanical water pumps.
- Economical and durable.
- Low cost.
- Simple design.
- No need for electricity or other power sources.
Disadvantages Of Hand Pump
- Requires regular maintenance for sustainable use.
- Requires significant physical exertion for pumping.
- Difficulty in obtaining spare parts.
FAQs
What is a hand pump?
Hand pumps are those that are manually operated as opposed to using air or electricity. Hand pumps come in two varieties: centrifugal and positive displacement, which use twin diaphragms or pistons. For centrifugal hand pumps to be self-priming, a foot valve is necessary.
What are the disadvantages of hand pumping?
The primary drawbacks are the necessary upkeep, the considerable physical strain involved in pumping, and the possible challenge of obtaining spare components, which may not be readily available. In order for a pump to be utilised sustainably, it has to have regular maintenance performed.
What does it mean to pump hands?
In order to shake someone’s hand, you must hold it and move it up and down, especially to greet them. SMART Vocabulary: terms and phrases that are linked to greetings, welcoming, and greetings.
How long do you use a hand pump?
You will continue to pump until your breasts feel exhausted and your milk supply stops. With a decent double electric pump, that typically takes eight to fifteen minutes, and with a manual pump, it can take up to forty-five minutes. After roughly two minutes of pumping, you will know you are done when no more milk comes out.
What are the three types of hand pumps?
However, it appears appropriate to group them into three major types based on the technology employed for the “pumping” part: rotor, diaphragm, and piston in order to better comprehend their properties.