Selecting the right borehole pump in South Africa is essential for keeping running costs low and the lifespan and water supply of your borehole pump high. But how can you find out which one is right for you? AQS Liquid Transfer has compiled a handy guide to help you choose a borehole pump for your needs in South Africa.
This guide will answer the following questions:
- What is a borehole pump and why do I need it?
- What happens if I select the wrong borehole pump?
- Why are borehole pump sizes important?
- How do I choose the correct power supply?
- Can my pump operate at the correct immersion level?
- What flow and pressure rate will I need?
- What if the ground has a high sand level?
- What other factors do I need to consider?
What Is A Borehole Pump And Why Do I Need It?
The drought in South Africa has seen dam levels drop by as much as 60% and has seen us experience the largest drought in 100 years. A borehole is a relatively narrow hole that is drilled so that a water supply can be reached. The borehole is on average between 30 – 100m in depth.
The borehole pump is the vertical pump that allows the groundwater to reach the surface. There are some key requirements to a borehole pump, like material resistance, but the borehole pump requirements will depend on many factors, like water depth and sand levels.
What Happens If I Select The Wrong Borehole Pump?
Selecting the correct borehole pump is important. A borehole pump should last the owner up to 10 years or more. Over time, the cost of maintaining the pump will always exceed the cost of the original pump, which is why the right pump is essential for reducing maintenance costs.
AQS Liquid Transfer has compiled this guide so that you don’t have to encounter additional costs or purchase fees due to selecting the wrong borehole pump. It is also important to consider what you are using the borehole pump for – irrigation, household use, farming, mining, or filling a tank or reservoir – as these will all have a bearing on what pump you need.
Why Are Borehole Pump Sizes Important?
Boreholes pumps tend to range between 4 – 6 inches, with smaller boreholes at 3 inches, and 8 inch boreholes used for more industrial water pumping requirements. At AQS Liquid Transfer we stock the full range of pumps from 3” Borehole motors through to 8” borehole motors for agricultural or industrial use.
Each borehole will be drilled to a specific diameter, which will help you select the right borehole pump size. It is important to consider the age of the borehole and measure the diameter before you buy the pump, as the sides may have corroded or built-up deposits over time, meaning a different diameter is now required.
How Do I Choose The Correct Power Supply?
Simply put, you need to check what power supply you have available at home or on-site. Models come in 220V, 380V and even 525V for our 6 and 8 inch borehole pumps. You will also see reference to single-phase or three-phase models. Single-phase refers to a pump powered by a single source of power, while three-phase is a pump powered by three sources of power throughout the pump.
Can My Pump Operate At The Correct Immersion Level?
You need to know how deep the borehole motor will be submerged underwater. In other words, the level from where the water starts to the level where the motor is situated. Check your borehole pump before purchase to ensure it meets the requirements for that depth.
However, the pressure handling of borehole motors are measured in bars – e.g. this 4” Vega oil-filled motor can handle pressures of up to 20 bars that is equivalent to the submersion depth of 200m, while our larger models can support pressures of up to 35 bars (equivalent to 350m) at both 6 and 8 inches. Bars are the effort it takes to push the water vertically upwards. 1 bar equals roughly 10m of borehole. When purchasing your motor you’ll need to consider the immersion level based on the bars listed on the unit description.
What Flow And Pressure Rate Will I Need?
Flow rate is how fast the water needs to be pumped. Flow rate also depends on how many functions the pump is fulfilling – e.g. irrigation systems, size of tank and size of the dam. The same applies to the number of units the pump is directed to for industrial use.
Pressure rate is the calculated pressure at which the system needs to operate – it will be impacted by a few factors, like:
- How far away is the endpoint from your pump?
- Do I need low or high pressure at the endpoint?
- How deep is the borehole and what is the level of the water?
- For irrigation applications, how many sprinklers will operate at a time?
- What is the elevation of the ground from the pump surface to the furthest point?
Considering these will help you find the right flow rate for your borehole pump, and ensure the machine is running at its best energy and cost-efficiency.
What If The Groundwater Has A High Sand Level?
If your groundwater has a high sand or silt level, this can impede the functioning of the pump, so you’ll need to consider this as part of your purchase requirements. Sand can clog or corrode the pump, blocking it or causing damage over time.
When purchasing a unit with AQS Liquid Transfer, each unit will list the sand content the pump will take, so you don’t have to be concerned about damaging your borehole pump.
What Other Factors Do I Need To Consider?
Borehole pumps have a variety of innovative functions that make it possible for you to enjoy a consistent and steady water supply:
- Do I need a horizontal or vertical installation? Our 6” borehole pump for instance supports both horizontal or vertical installation.
- Should I go with water-filled or oil-filled motors? This is dependent on the submersion depth of the borehole. AQS Liquid Transfer stocks both water and oil-filled models.
- What type of motor do I need? The type of motor required is determined by the kilowatt and diameter of the pump as well as the available voltage.
- Will a Vega borehole motor fit on another brand model? Yes, all our borehole motors are manufactured according to the NEMA standard.
Do you still have questions? Give our AQS Liquid Transfer team a call on +27 12 548 7204 or fill out our enquiry form, our friendly team will get back to you with first-hand expertise on how to select a borehole pump for your needs.