The FMG-HP series rotary gas meters are designed to meet the highest demands for reliable and accurate measurement of gas flow under high-pressure conditions. The meters fully comply with OIML R137 1&2 standards and can therefore be used for all legal measurement applications. The actual meter body is made of aluminium and held in place by a steel meter casing. This casing holds the meter body in place without any stress between adjacent flanges. Since the meter body is not affected by stresses from flanges or pipes, the clearances between the vanes and the body are optimized. Therefore, the excellent metrological performance achieved with the low-pressure FMG rotary meter is also maintained under high-pressure conditions.
To ensure high accuracy and wide-range protection, it is essential that the displaced volume does not change within the operating conditions range. By isolating the meter body from the actual pipeline and using the same material for the vanes, changes in displaced volume due to installation stresses, operating pressure, and thermal expansion are eliminated.
Due to its 1:100 measurement range, the FMG-HP rotary meter is very suitable for small city entry stations where the actual load of these measurement stations varies greatly. Square vanes and improved positioning of the main bearings make the cartridge very robust and less susceptible to flow and pressure surges. Unlike other approved flow measurement devices such as turbine meters and ultrasonic meters, a rotary meter can be installed close to regulators and without long straight pipes or specially prepared inlet sections.
For safety, the FMR-HP series can be equipped with a spring-loaded bypass valve. If a meter locks, the bypass valve opens, allowing gas to pass through. This supply security feature makes the FMR-HP suitable for critical installations where gas flow cannot be interrupted.