Quadrina flowmeters




the probeflo insertion flowmeter for the measurement of potable water


Probeflo insertion flowmeters that were originally supplied by Quadrina Limited are used extensively, on a worldwide basis, for the measurement of potable water supplies in pipelines from 65mm nominal bore to virtually any diameter and of any material. This range of flowmeters, together with spares and backup is now available from Jestim Limited.


They can be used in a wide variety of applications such as distribution or network analysis, for leak detection programs, for permanent flowmeter installations, for bulk flowmeter verification or calibration checks and for many other purposes. The bi-directional versions not only measure the water flowrate, but can also show flow direction. This can be a very useful feature when monitoring the time related balance of a complex distribution network where flow direction can often change. Another application might be for reservoir in-flow/out-flow measurements. The list is extensive.


A major advantage of probeflo flowmeters, in addition to their cost effectiveness, is the ease with which they can be inserted into and removed from a pipeline without interruption to normal flow, and with no spillage. This is achieved by the use of a small wedge gate or ball valve mounted on the side of the pipe through which the flowmeter is inserted. when removing a flowmeter from the pipeline it is simply withdrawn through the valve which is then shut to allow the flowmeter to be taken away.


Furthermore, probeflo flowmeters require just micro amps to power them which makes them eminently suitable for portable or transportable applications since large battery packs are not needed. Most of the probeflo series can be powered for continuous operation for periods of up to 12 months on a single set of 3 AA alkaline cells, these batteries being inexpensive and readily available on a worldwide basis. The battery pack fits a special holder in the flowmeter's IP67 rated headbox and a simple battery test function is included for checking the battery condition.


In operation probeflo flowmeters produce a linear output with respect to actual flow, thereby having an extremely wide turndown ratio. The flowmeters' measurements are unaffected by vortices shed by the flow head (for some flowmeters vortices can cause severe deviations to their linearity performance), neither are they affected by the material of construction, nor the thickness of the wall of the pipeline. Also, they do not have electrodes to contaminate and spoil their operation and they do not need particulates, bubbles or other disturbances in the water to derive flow signals.


A major feature is that the probeflo can closely track the velocity profile in a pipe, something that few flowmeters can do, but it is vitally important if good quality flow measurements are required.


Significantly, probeflo flowmeters are exceptionally tolerant to vibration and to fluid swirl within the pipeline and do not, as some other devices do, measure a vectorial sum of axial velocity and swirl velocity.


They are easily checked for operation before inserting them into a pipeline, simply by blowing on the flow head. They are a very easy and straightforward device to service in the field, but in the event that factory assistance should be required, Jestim offer this on a quick response, fast turn-round basis - usually on a 24 hour return with courier backup when required. Generally, spare parts are available ex-stock.


To obtain full flow analysis, and to determine the flow in terms of volumetric units, it is necessary to know the exact internal diameter of the pipeline. The Jestim Gauging Rod is a simple device that can be inserted into the pipeline in place of the flowmeter, on a temporary basis, to enable the internal diameter to be quickly measured. No special skills are necessary to use the Gauging Rod except a tape measure.


For data logging purposes the probeflo flowmeter can be configured to be compatible with most data loggers currently used by the water industry. For individual needs, flowmeters can be tailored to customer specific requirements in terms of exact insertion length, types of displays fitted to the headbox, particular output signal requirements or special materials of construction. Jestim offer maximum flexibility in these options, working closely with the customer to determine the best configuration.


A computer-based program is available to assist with the determination of the velocity profile at a given installation. The Velocity Profiles Package is available to run on an IBM compatible laptop computer. This software quickly performs a log-linear traverse to BS1042 to establish the velocity profile; the mean flow and the ratio of mean flow to centreline flow, automatically correcting all measurements for blockage effects caused by the introduction of the flowmeter into the pipeline. No special computer or mathematical skills are necessary for the operator to be able to use the program and obtain meaningful results.






RSP - Last Modified 21-07-06 - Jestim Limited, All Rights Reserved