Gardening is a popular activity for many people, and ensuring your garden is well-nourished and hydrated is essential to maintaining a healthy and vibrant outdoor space. We have previously discussed effective water management in your garden by creating a sprinkling system.
Here we add another tool to your system: the self-priming water pump, which can significantly improve how you manage water in your garden. This article will dive into how these pumps work, their unique features and their advantages.
So, let's begin your journey to a greener and more sustainable garden.
---------------------------------------------------------------------------------------------------------------------------
Functional Principle of Self-priming Water Pumps
Traditional pumps require manual priming to remove air from the system before pumping water. However, as the name suggests, self-priming pumps can prime themselves by starting the pumping process with only air. Priming is achieved by impeller rotation, pushing the incoming liquid out of the centre and creating a vacuum, which results in further suction.
Self-priming pumps are a popular choice for many home applications today because of their ease of use, versatility, and ability to handle a wide range of fluids.
Maximum Suction Height
There is a limit to the maximum suction side head that a self-priming pump can reach. This limit on the suction side is determined by atmospheric pressure and is called the maximum suction head. According to Torricelli's principle, a self-priming pump's maximum theoretical suction head is 9.8 meters. Since water in the well is also subject to atmospheric pressure, regardless of the vacuum created by the pump, the fluid itself, which is in a low-lying area, will not be able to rise above 9 meters in reality. If the terrain is elevated, these pump rise rates will go down to 6â7 meters.
A Torricelli vacuum is created when dirty water is sucked up to a height of more than 10 m.
Alternatively, you can make locate the pumping unit at a lower relative level to be able to pump the water to a much higher level.
Types of Pumps
There are several types of self-priming pumps on the market, each with its unique features and advantages. The main types of self-priming pumps are:
a. Centrifugal pump with a built-in priming mechanism. This allows the centrifugal pump to evacuate air from the suction line and start pumping water without manual priming.
This includes our most popular JA/JAM-series pumps (Pentax CAM):
As well as the more compact PA series (Pentax AP series) pumps with Noryl impeller:
And Brass impeller versions with "/1" for example PA 100-4"/1 for extra durability.
As well as Three phase versions which are coded with "T" letter for example PA 100-4" T and PA 100-4"/1 T.
b. Positive displacement pump is a type of positive displacement liquid pump with a built-in self-priming capability or mechanism. These pumps use a rotating element, such as a piston, gear, or paddle, to create fluid or liquid flow through the pump housing. Self-priming positive displacement pumps are especially useful for handling pourable, viscous liquids, fluids, and slurries. The most obvious example of a piston pump is the standard hand-held water pump for artesian water.
And three-phase version PE50AT.
c. Liquid ring pump is a type of centrifugal pump that uses a liquid ring to create a vacuum and lift fluid into the pump. The pump has an impeller that spins the liquid around a chamber, creating a centrifugal force that compresses the liquid ring and creates the vacuum. As the vacuum is created, the pump draws fluid into the impeller, allowing it to be pumped through the discharge port.
The liquid ring also acts as a seal, preventing air from entering the pump, and making it self-priming. This type of pump is commonly used in applications where a high suction lift is required or the fluid being pumped contains air or gas.
Main Components
A self-priming centrifugal pump consists of a motor and an operating chamber with a discharge mechanism. The pump shaft and motor are connected via a coupling or the impeller. Seals ensure tightness. Several key components work together to allow the pump to prime automatically.
a. The pump casing or pump body contains the impeller, the rotating component of the automatic pump that moves the liquid through the pump. The blades are bent in the opposite direction to the movement of the impeller. As they move, they push the water around, pushing it against the walls of the casing. This phenomenon is called centrifugal force, and the area between the blades and the wall is called the "diffuser". So, the impeller moves, creating an area of increased pressure at the periphery and pushing the water towards the outlet (discharge line). At the same time, a low-pressure zone is formed in the centre of the impeller. Water from the supply pipe (suction line) is sucked into it. Then the water is pushed to the walls by the impeller and by centrifugal force is pushed into the discharge line.
b. The suction line is the pipe that connects the working chamber of the pump to the water source. Centrifugal self-priming pumps have an exciting construction of the working chamber - in the form of a volute. The impellers are fixed in the centre of the casing. There can be one wheel, then the pump is called a single-stage, or there can be several - a multistage design. Single-stage pumps always work at the same capacity; multistage pumps can change the capacity depending on the conditions, respectively are more economical (less power consumption). The suction line is well above the impeller's axis of rotation, which allows the pump to automatically have a constant amount of water in the priming chamber. This creates a vacuum in the suction line and removes air when starting work without water filling at repeated start-ups.
c. A check valve is a one-way non-return valve that prevents the backflow of liquid in the system. In a self-priming pump, the check valve plays a decisive role in the priming cycle of the pumped liquid, ensuring that air is removed from the suction line and that the pump sucks efficiently. By its operating principle, the impeller of a centrifugal pump cannot generate centrifugal force from the air, so the casing is filled with water before operation. Since pumps are often operated intermittently so that the water does not flow out of the housing at the stoppage, a check valve is placed on the suction pipe. If the check valve (it is obligatory) on the supply pipe is at the bottom of the suction pipe, then the whole pipe has to be filled with liquid.
There are also external check valves available:
Advantages of Using Self-priming Water Pumps
Using a self-priming water pump in the garden has advantages, including the following:
a. Easy and convenient, without manual priming, which can be time-consuming, labour-intensive and error-prone. With a self-priming pump, you can simply turn it on and let it handle the priming process automatically, saving you time and effort.
b. Working with air bubbles. Self-priming pumps are designed to handle viscous liquids, suspended solids and air bubbles, making them the ideal choice for heavy-duty applications involving mixing and transferring water and other liquids. This can be especially useful in agriculture, where you may need to mix water and liquid additives or pump water with fertilisers, pesticides or other additives.
c. Versatility. Self-priming pumps are versatile and can be used for various pumping operations, including water distribution and transfer, irrigation, drainage and more. This makes them an excellent choice for water distribution, irrigation, automatic sprinkling and more, no matter the size or complexity of your garden.
Use-cases
While the self-priming pumps are used extensively in industrial, hygienic, and civil applications, we will focus on their domestic uses for your garden.
Diesel fuel transfer is a common application for self-priming pumps because they can efficiently pump large quantities of diesel fuel without manual priming. This makes them an excellent choice for powering heating systems, construction equipment, generators, and heavy-duty diesel water pumps. Remember fire safety, and flush and dry the pump after use. Oil-resistant seals should be used for continuous use.
Chemical applications are made easy without the need to prime the pump and get covered in difficult-to-wash substances. For this reason, this type of pump is often used also to pump waste water, corrosive liquids, light weight oils or lubricating oil.
Automatic pumping: the pump's self-priming ability makes it ideal for intermittent pumping operations. Using a pressure switch, you can start up the pumping process automatically when water is drawn, creating a constant presence of water. For this, consider adding a pressure switch.
Conclusion
In conclusion, self-priming water pumps are an excellent investment for those looking to improve the efficiency and sustainability of their garden water management system. These versatile pumps offer several advantages, including easy and convenient initial priming, handling air bubbles and liquid additives, and a wide range of applications.
By choosing the right self-priming pump for your garden, you can enjoy a greener, more sustainable outdoor space that is easier to maintain and better for the environment.
If you are ready to take the next step toward efficient water management in your garden, consider investing in high-quality equipment. Choose well-known, quality European manufacturers and don't settle for a cheap solution with subsequent problems with both operation and repair of the pump.
The right pump will help you create a more environmentally friendly and efficient garden that you can enjoy for years.