Electricity + Control July 2016

FLOW MEASUREMENT + INSTRUMENTATION

Measurement technology for tunnel drainage After 20 years of planning and construction, Switzerland celebrates the completion of the Gotthard BaseTunnel. At 57 kms, it is the world’s longest railway tunnel. 2 300 metres of solid rock rises above the new line at its deepest point.The construction must not only withstand extreme mountain pressure but also substantial volumes of mountain water must be prevented from seeping in.To make sure the entire tunnel stays dry, two drains were laid in the floor of each of the single-track tubes.The drainage system sepa- rates the (clean) mountain water from the (mostly clean) wastewater that is drained off for removing impurities during operations or in the event of an accident. Every second, five liters of wastewater are carried away from each tunnel tube in every direction. The water is collected in catch basins at both ends of the tunnel and checked for any pollution. The measurement technology for the tunnel drainage originates from process automation specialist Endress+Hauser : 180 instruments, some explosion-protected, and three measuring panels detect flow volumes and levels of mountain and wastewater, conductivity, the pH value and the turbidity of the wastewater. For Stefan Bürki, the project manager in charge of the project at Endress+Hauser Switzerland, the installation has a very special meaning and stated: “I am proud to be part of this once-in- a-lifetime project!” Enquiries: Email suanne.willemse@za.endress.com or visit www.za.endress.com

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fact Reliable flow measurement and process diagnostics, also under harsh conditions Flow measurement – technology driven by KROHNE • Complete product portfolio spanning over all measurement principles and for all applications • Process safety and process optimisation through build-in diagnostic functions • Industry-specific solutions and services for the entire product life cycle

For low flows KOBOLD Instrumentation, represented in South Africa by Instrotech – a Comtest Group company, is offering their model KSV flow meters and switches for very low flows with and without control valves – so even the lowest possible liquid or gas flow rates can be measured. Specifically for liquids or air, the KSV operates on the suspended float principle.The direction of flow is from bottom to top, and the installation position is vertical. The indication point is the upper edge of the ball.The device has been designed

as a simple, and thus economical measuring sys- tem. The optional needle valve allows economical control and the device has been designed for panel mounting. Kobold’s KSV flow meters are acid and caustic-proof, made of polycarbonate and brass or polysulfone and stainless steel materials.They are highly suited for advanced applications in medical technology because these units are sterilisable, operating at temperatures of +120°C.They can also be used for a wide range of applications in the ana- lytical instrumentation field, within production and environmental monitoring, as well as in laboratory measurement and monitoring technology. Enquiries: Instrotech.Tel. +27 (0) 10 595 1831 or email sales@instrotech.co.za

KROHNE South Africa 8 Bushbuck Close, Corporate Park South Randjiespark, Midrand, Tel.: +27 113141391 Fax: +27 113141681, John Alexander, j.alexander@krohne.com, www.za.krohne.com

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