Borehole, how much water can I extract
Borehole, how much water can I extract When trying to determine the volume of water one can draw out of a borehole, it is crucial to have an accurate water yield test report. The driller of the hole will conduct a draw down test to determine how much volume the aquiver is providing to the specific well (hole). Should it be producing 100 litre per minute for example, we recommend that the user not install a pump greater than 50% of the yield. The reason for this is that the actual well will not pull down completely and the level in the hole will remain static with a 50% draw from the yield. Premature borehole collapse is encouraged by rapid adn excess extraction by installing borehole pumps which are capable of removing the full yield volume or even more per minute. Pedrollo 4 SR submersible deep well pumps provide a quality and efficient solution to both standard and solar power options. In South Africa we do not find any demand at this stage for 6″ pumps. Please contact our sales team for qualified free information and assistance in pump selection.
Pump pressure control system
Pump pressure control system The simple pump pressure control system available from Pedrollo, South Africa has many advantages. We often have the request to assist with the design on systems where water is pumped from a dam. river. pond/ bulk storage to a service tank next to a home etc. The problem seems to occur when the user becomes embroiled in working on complicated control systems and ends up with horrific costs for cable runs or radio telemetry systems. The simplest system to use is to have the pump fitted with either an electronic pressure/flow controller like the Pedrollo Easy Press or a Hyrdrosphere/pressure switch system. Pedrollo Easypress This controller activates if it recognises a flow demand and / or a pressure set point. The really great feature of the Pedrollo Easy Press is that it has a storage vessel to buffer the pressure on/off switch. This buffer zone is fantastic for two purposes, potential dry run operation (lack of water on the suction side of the pump like an empty dam or low water level in the source) and long discharge pipe lengths. This buffer is essential to enable the unit to switch positively and not to instantly switch when the contacts would close and open with oscillating flow. Once one has a pump fitted with an automatic controller the rest is relatively simple. A ball float valve or a solenoid valve at the point of delivery completes the cycle. Basically the pump reacts to the line pressure. In this case the ball float valve in the receiving tank rises and closes the valve, pressure in the line builds and flow slows. As the flow stops with the closed valve condition, the controller (which is located at the pump and can be up to 200 meters away from the pump) stops the pump. Water usage from the tank will drop the water level, the ball float drops with the water level, opening the valve, releasing pressure and generating flow. The controller sees the resultant flow and pressure drop and the pump starts. We do like to use the older technology HYDROSPHERE PRESSURE PUMP systems in long er pipe runs. The size of the hydrosphere must be linked to the pump flow at the operational head of the system. We like this system for very long pipe runs up to a few Km due to the added protection provided to the motor for stop/start conditions. The hydrosphere tends to absorb and delay stopping and starting due to pressure and flow variations in longer pipe runs, small leaks, air entrainment etc. One does need to ensure that the pumps are protected with the correct overload protection. We like to recommend a proper control panel be installed with the pump which includes surge protection. In Southern Africa with power cuts, brown and black outs which can be frequent, it is crucial to ensure the electrical components are adequately protected. The above represents the simplest way of controlling a pump remotely without using […]