Gas measurement at low and high operating pressures
Elster-Instromet TRZ2 turbine gas meters are robust meters for use in stationary conditions. Over years they have proved themselves to be highly accurate and reliable devices for measuring the flow of gaseous substances.
With the patented Elster-Instromet measuring cartridge it is possible to save service time by replacement of the cartridge on site.
The measuring cartridge is supported with O-rings, is free of tension and is, therefore, not affected by any influences stemming from the housing or the ambient conditions such as temperature fluctuations.
The gas flowing through the meter sets a turbine wheel in motion and the number of revolutions of the wheel is proportional to the passed volume. The gas entering the meter is accelerated by a special designed and patented fl ow straightener, located at the meter inlet. This flow straightener is designed in such a way that any potential fl ow disturbances such as swirl or asymmetric flow are eliminated. Because the flow velocity is increased, the driving impulse on the turbine wheel is also strengthened. This means that it is possible to achieve a high accuracy within the permissible error limits, even with low flow rates. The flow onto the turbine wheel is axial and the wheel is run on the main shaft with robust dimensioned ball bearings.
The revolution of the turbine wheel is reduced by a gear. Via a magnetic coupling, a transmission shaft drives the 8-digit mechanical roller counter located in the pressureless totalizer head. After the gas has passed the turbine wheel, a pressure recovery is achieved in the outlet channel, which is designed to create optimum flow conditions.
Elster-Instromet TRZ2 meters are manufactured in accordance with DIN EN ISO 9001:2000 and DIN EN ISO 14001. They are designed, produced and tested in accordance with the following guidelines, standards and references:
- EC Directive 71/318/EC or directive 2004/22/EC (MID)
- EC Directive 97/23/EC concerning pressure equipment (PED)
- EC Directive 94/9/EC concerning explosion protection (ATEX)
- Applied European standards (et al. EN 12261)
All manufactured meters are tested by offi cial, PTB approved test rigs. Test certificates in accordance with PED requirements are available for pressure and strength tests.
The housings are made of GGG-40 (ductile iron) or steel. The meters meet the highest safety standards and are fire-proof (HTB).
- Turbine gas meters with measuring cartridge
- Aluminium fl ow straightener DN80 – 150
- Meter types G 65 – 1000
- Flow range 5 – 1600 m3/h
- Diameters DN 50* – 150 (2” – 6”)
- Pressure rates PN 10 – 100, ANSI 150 – 600
- Temperature ranges:
MID: -25 °C to +55 °C (Qmin ≠ 8 m3/h)
PED: -25 °C to +60 °C (steel)
ATEX: -20 °C to +60 °C
- Manual oil pump (standard for PN 25 – 100 and ANSI 300 – 600)
- Compact installation, inlet pipe length L ≥ 2 DN
- Length 3 DN
- Thermowell built into meter housing (optional)
- Integrated HF-pulser (optional)
- Absolute-ENCODER S1 (optional)
- EC, MID as well as different national approvals (e.g. PTB)
- Media: natural gas, petroleum gas, town gas, nitrogen, argon, further gases on request