Pressure Vacuum Level Ltd is the UK's largest distributor of Pressure & Vacuum Switches, Level Switches and Sensors, Flow Switches & Meters for the Hydraulics, Pneumatics, & Processing Industries.
News Letter No. 14
How do you measure the flow of a liquid so corrosive that it destroys flow switches?
Kelco flow switches have no metal parts that contact the process fluid. Just plastics that are inert to corrosive fluids such as seawater, brine, and solutions with high (or low) pH. So using Kelco flow switches enables you to measure flow with no unwanted reactions between process fluid and the switch, and no switch failures because of corrosion.
The Kelco F25 (illustrated) is extensively used for flow status signalling in water treatment plants, for control of effluent and fluid neutralising systems and for corrosive and saline ground water applications. The F25 also has extensive applications in safety and control signalling for chemical handling, control of flow in ultra pure water systems and irrigation control. Kelco flow switches have fully adjustable flow sensitivity, and the range includes inline flow switches, paddle flow switches and trailing wire flow switches.
If you are into neutralisation, precipitation, flocculation and disinfection in wastewater treatment, you’re going to need the latest digital dosing equipment kit like the latest Martens conductivity level sensors for measuring conductivity with either 2-electrode or 4-electrode probes, or the Martens capacitative level sensors that lets you do level measurements using immersion probes in liquids with conductivity >30µS/cm – all totally new and part of a huge new range in the PVL catalogue. The capacitative level sensor lets you do real text programming, to set the measurement range between 0 – 200mm and 0 – 2500mm, and to program the measurement unit almost any way you need. Full information is available from the PVL engineering team at 01892 664499. More...
Need to detect flow of less than 5ml per minute
The chemistry of water treatment, and of wastewater recycling has changed in a big way during the past decade or so, and the much greater precision of dosing required makes intelligent dosing using flexible intelligent electronic control essential. Much greater concentrations of dosing chemicals, which reduce chemicals cost, also make it essential that operators are able to measure and control precisely how much chemical is being dispensed, to eliminate wastage and the environmental risks of over-dosing.
The Kelco CR20 microflow switch is a compact in-line flow sensor designed to detect extremely small flows and is capable of monitoring flows – or the lack of them - of less than 5ml per minute. That makes the Kelco CR20 perfect for verifying the efficient function of modern micro-dosing systems. Like all other Kelco products, the CR20 microflow switch has no metal parts in contact with the process fluid, so are unaffected by aggressive or corrosive chemicals or extremes of pH. Handling continuous flows of up to 4 litres per minute, either pulsed or continuous, the CR20 handles pressures to 18 bar and can be fitted to pipes from 6mm to 20mm.