A public utility company of a city in northwestern Germany supplies approximately 22.000 residents with natural gas. Its network encompasses an underground pipeline system of about 80 miles length. The natural gas distribution is carried out with a pressure of 10 psi, where the gas supplied to the end users reaches 1 psi.
For an analysis of the network, but also for rapid localization and repair of possible disturbances, turbine wheel flow meters have been placed at various points in the natural gas medium pressure net. However, these types of meters have not been sufficient in terms of measuring normalized volume streams. Retrofitting or converting the gas transfer and metering stations with other intrusive metering technologies would have been a very costly alternative, including the interruption of the gas supply.
FLEXIM offered the cost effective alternative: Non-intrusive gas flow measurement using clamp-on ultrasonic flow meter technology - even at buried pipelines.
In this specific case the subsurface PE pipeline at the measuring point has been exposed in order to mount the IP68 submersible clamp-on ultrasonic transducers. By selecting appropriate measuring points with long straight lengths upstream and downstream, a high measuring precision is achieved. The buried non-intrusive flow meter is not subject to mechanical wear and therefore offers a long lifetime and high reliability. Its is optimaly protected in its rugged stainless steel VARIOFIX mounting fixtures. Expensive shaft constructions as well as supply interruptions are avoided. Data transfer via the local GSM network is possible.
- Very cost effective retrofit solution with a high degree of accuracy and reliability
- Simple installation without interruption of the gas supply
- Subsurface installation possible without any problem
- No mechanical wear or tear of the flow meter
- High turndown ratio
- No leakage risk through the measuring system