The turbine flow meter is a speed type instrument, which has advantages of high accuracy, good repeatability, no zero drift, high turn-down ratio, simple structure, few moving parts, high pressure resistance, wide measurement range, small size, light weight, low pressure loss and convenient maintenance.
The turbine flow meter has high-quality bearings and specially designed guide vanes, so it greatly reduces wear and is not sensitive to peaks, and can even give reliable measurement variables under harsh conditions.
It has a wide range of use value in industries such as petroleum, chemical industry, metallurgy, food, biochemistry, and urban gas pipeline network.
1. According to the purpose of measurement
This includes the selection of instantaneous flow or cumulative flow, flow display unit, measurement accuracy, repeatability, linearity, flow range, measured temperature, pressure loss, temperature and pressure compensation, output signal characteristics and response time, etc. Different measurement objects have their own measurement purposes, and they have different focuses in terms of instrument performance.
2. Requirement of measuring medium properties
Chemical corrosion and fouling, and chemical properties of fluid sometimes become the decisive factor in choosing the measurement methods and instruments of turbine flow meter. Certain fluids can cause corrosion of the instrument contact parts, surface scaling or precipitation of crystals on the metal surface which will have electrolytic chemistry reaction.
3. Requirement of measuring medium composition
There are differences between the measurement of flows of multi-phase and multi-component medium and that of flows of single phase change medium. The turbine flow meter measures single-phase and clean medium, while the electromagnetic meters can measure solid-liquid two-phase mixed medium.
4. Requirement of compression system and other parameters
We need know the compressibility value of the measured gas to obtain the fluid density under working conditions. The density of fluids with a fixed composition is calculated by pressure, temperature and compressibility; Fluids with variable composition and working close to (or in) the supercritical region should consider online density measurement.
5. Requirement of measurement accuracy
It is necessary to clarify the overall measurement accuracy requirements and whether it is used under a certain flow rate or whether there is a significant change due to temperature and pressure changes within the measurement range. The value is generally low, and the difference between various gases is small. The commonly used accuracy grades of smart liquid turbine flow meters are 1.0 and 0.5. This accuracy grade is higher than that of general rotor type flow meters. Thus, it is a good choice for customers with higher accuracy requirements.