Borehole Pressure Tanks store water and provide water under pressure when the pump is not running. It builds up a reserve supply of water so the pump starts and stops less often, prolonging the life of the pump.
The operation of a pressure tank is based on physical properties. Water cannot be
compressed into a smaller area, while air can. When water is pumped into a tank
containing air, the air is compressed, putting the water under pressure.
The more the air is compressed, the greater the water pressure. When the water reaches a
preset pressure, typically 40 to 60 pounds per square inch (psi), the pump automatically
shuts off. As water is used, the pressure in the tank is lowered.
When the water reaches a preset pressure, typically 20 to 40 psi, the pump starts again.
The minimum tank pressure must be at least as high as the pressure needed by any
water-using fixture or appliance. Many require at least 10 psi to operate properly. Water
treatment units, water softeners, clothes washers, and dishwashers may require higher
water pressure to operate properly; possibly as high as 30 psi or more.
There are different types of pressure tanks. Older types of pressure tanks include
galvanized steel tanks and galvanized steel tanks with a floating wafer. Today, pressure
tanks with a diaphragm or a rubber bladder are common.
Up until 1970, the most common type of pressure tank used with a private water system
was a galvanized steel tank. A disadvantage of the galvanized steel tank is that air and
water are in direct contact with each other. Water can absorb some of the air, so the air
must be replaced to prevent the tank from becoming waterlogged. If this happens, there is
little air left in the tank to become compressed, so the pump runs nearly every time water
is used. In addition, too much air in the tank is a problem because it reduces the space for
water storage. Extra air must be released or the tank will become air-bound. An air-
volume device attached to a steel pressure tank will control the volume of air
automatically. The steel galvanized tank with a wafer has a floating wafer that separates
the air from the water.
since 1970, most private water systems have used bladder-type pressure tanks. The
bladder is a bag usually made of butyl rubber or flexible polyvinyl chloride. The water is
contained in the bladder and does not come in direct contact with the air in the tank. The
bladder holding the water expands into the pressurized air space in the tank as it is filled.
As water is used from the system, the bladder collapses until the water is almost emptied.
The water is
contained in the bladder and does not come in direct contact with air in the tank. The
bladder holding the water expands into the pressurized air space in the tank as it is filled.
As water is used from the system, the bladder collapses until the water is almost emptied
before the minimum pressure is reached, activating the pump. They are pressurized at the
factory (typically around 20 psi) but the pressure can be adjusted using an air valve
located near the top of the tank. Because there is almost no water left in the bladder at the
pressure when the pump is turned on, these tanks may not be suitable for low-yield wells
(eg, very slow pumping rate) unless an additional tank is used. Diaphragm pressure tanks
are also used. The diaphragm is a membrane that separates the water and air in the tank
One way to select the proper size for a pressure tank is to base it on the pump's flow rate. A
typical private water supply pump supplies water at a rate of 5 to 10 gallons per minute
(gpm). Multiply the flow rate by four to determine the size of a diaphragm or bladder tank.
For example, a 9-gpm pump would require a 36-gallon storage tank. This would be the
same sizing formula to use for a galvanized steel tank with a wafer installed. A galvanized
steel tank without a wafer is sized 10 times the flow rate; a 9-gpm pump would require a
90-gallon storage tank. Work with your pump supplier to determine the proper pressure
tank size for your water system.
As with any formula, there are exceptions, including systems with low-yield wells. Your
pump supplier can determine the proper pressure tank size if you have a low-yield well.
In addition, water pumps and motors designed for use with variable frequency drive (VFD)
motor controllers are popular, especially with submersible pumps. These are called
constant-pressure water systems since the controller determines the speed of the pump
motor needed to maintain the pressure. When water is used, the pressure drops and the
pump speeds up. When water use slows down or stops, the pressure increases and the
pump slows down or stops.
Anear-constant pressure is maintained. For most household use, a VFD-controlled water
the pump needs only a small pressure tank; usually | up to 2 gallons.
Book A Consultation: Just give us a call or WhatsApp +263 78 860 8009.
Services We Offer:
1. Borehole Siting.2. Borehole Drilling.
3. Water Reticulation.
4. Borehole Repairs.
5. Tank Installations.
6. Pump Installations.
7. Solar Water Systems ... etc.
Water Is Our Business!
You Can Also Call Us On: +263 78 876 6701, +263 78 876 6706
Email: info@nakisoboreholes.co.zw
Website: www.nakisoboreholes.co.zw
Nakiso Borehole Drilling: Your Trusted Partner for Safe, Sustainable Water Access
At Nakiso Borehole Drilling, we are your comprehensive partner for unlocking reliable water on your property. Our highly skilled team tackles all drilling projects, from standard boreholes to specialized Blast Hole and RC Drilling. We handle everything in-house for a seamless experience, encompassing expert borehole siting, efficient drilling, and pump installation – solar, electric, or manual – tailored to your specific needs. With Nakiso, your reliable water source is just a drill away.We don't just strive to be the best; we maintain the industry's strictest quality standards and are committed to sustainable practices for the future of Zimbabwe's water security.
For All Your Borehole Drilling Services Contact Us:
Five Facts About Borehole Drilling That You Need To Take Note Of:
1. Know Your Borehole Casings:The Preferred Borehole Casing In Zimbabwe Is Class 9 and 10 (Pressure Classes.)This is because Class 9 and Class 10 Casings are more collapse resistant. The strength of a Casing is often described as collapse resistance.
2. Borehole Drilling Depth: The exact depth, of where the water is located, cannot be established by the drilling contractor nor the Water Surveyor (Borehole Siter).
3. The Is No 100% Guarantee On Water: It is important to note that it is never a 100% guarantee that any hole will yield water, the amount and water quality can also not be guaranteed by the drilling contractor and water surveyor.
4. Borehole Siting or Water Surveying Is Important: Making use of a hydrologist or traditional water diviner will increase your chances of having a successful borehole that will yield a sufficient amount of water.
5. Know The Risks: The risk of the borehole drilling lies with the property owner. The client will still be liable for the drilling costs irrespective of a borehole yielding water or not.
Your smile is our commitment!
Business Offices: 65 Churchill Avenue, Alexandra Park, Harare North, Zimbabwe.
Call Us Today:
Office Numbers: +263 867 71 88844
Sales: +263 78 860 8009
Operations: +263 78 860 8005
Marketing: +263 78 876 6701
Email: info@nakisoboreholes.co.zw
Website: www.nakisoboreholes.co.zw
