Flow meter selection Trade settlement
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Our company is planning a heating system renovation, and the flow meter installed on the outlet main pipe will be used for trade settlements; we would appreciate it if experts could recommend suitable models. The specific parameters are as follows: Pressure: 1.7 MPa; Temperature: 280°C; Medium: superheated steam; Installation method: horizontal; Accuracy: 1.5% or higher; Range: 150 t/h. Our company has the following requirements: 1. Since this flow meter will be used for trade settlements, it needs to be inspected annually, so it’s preferable to choose a model that is easy to install and remove (the entire meter body should also be able to be inspected). 2. After the heating system renovation, the number of users may vary, so the flow meter should have a wide measurement range. 3. Low maintenance requirements. 4. Both the heating provider and the user will install a flow meter of the same model. Therefore, the error must not be large to avoid trade disputes. 5. Vortex flowmeters are not chosen, as our factory currently uses vortex flowmeters; these devices suffer significant wear over time, and they often fail inspection when sent for testing.
Choosing a flow meter to meet the above requirements can be somewhat difficult: 1. Orifice plates and nozzles are hard to remove for testing, and their range ratio is small. Medium precision 2: Vortex street – you think it won’t work. Medium precision. In fact, vortex flow meters are a more suitable choice; could the wear you’re experiencing be due to using a meter with an undersized diameter? 3. It is not very suitable for steam systems with moving parts such as turbines. Medium to high precision. 4. Anubaa and Weiliba are options; it’s worth inquiring to see if they are suitable. The precision is provided by the manufacturer for reference only
In fact, the most cost-effective option is a vortex flow meter with integrated temperature and pressure compensation. Throttle elements have a narrow range of operating values, and their cost is relatively high.
The most cost-effective option is an integrated orifice plate; you need to take other factors into consideration. Allen-Bradley is a good choice, and Rosemount’s products achieve accuracy at the level required for trade measurement
If vortex flow meters are not an option, then balanced orifice plates or Rotameters could be chosen
A nozzle flow meter or Anubis can be considered; both companies should use the same type of instrument for measurement.
If trade settlement is to be implemented, it’s best to use a mass flow meter – it requires less maintenance and offers high precision, though it is more expensive
For trade settlement, I saw that Rosemount’s integrated orifice plates are useful; they belong to the 3051S series, with the primary components being orifice plates, balance flowmeters, and Anubis. Delta Bar has also been used as a single-element device for measuring steam flow, but I didn’t pay attention to its accuracy.
Tubular differential pressure flow meters, such as orifice plates and nozzles, can all be used
In the past, steam flow measurement in large pipelines was carried out using orifice plates or balanced orifice plates; nowadays, various type of turbine flow meters are used. A differential pressure value is required, and by combining this with the temperature and pressure measured by additional sensors, the steam density can be determined from tables, thereby yielding the mass flow rate of the steam. The entire setup is complex, and it also requires insulation and heating. When measuring saturated steam, the reading may drop to zero inexplicably due to condensate blocking the pressure tap holes. The SIERRA multi-variable vortex flow mass flow meter allows for changes in the type of fluid and in the inner diameter of the pipeline. It features an online pull-out mechanism that enables maintenance without shutting down the system, and it can assist metrology institutes in issuing calibration certificates with a precision of 1.0. It can be used with fluids operating within a temperature range of up to 400 degrees Celsius or as low as -200 degrees Celsius. SIERRA multi-parameter vortex flow meter: process-connected, with linear output for temperature, pressure, flow rate, and mass flow rate; a 30:1 range ratio that **expands the lower measurement limit. It features built-in lnnova-Mass software for calculation, which automatically identifies saturated steam from superheated steam and carries out the necessary calculations, ensuring the reliability of measurements. It is the best choice for measuring steam trade in large pipelines. The attachment contains the selection results calculated based on the operating parameters provided by the original poster: (the measurable range for different diameters) DN300 = 4.97~203 T/h, DN350 = 5.98~244 T/h, DN400 = 7.9~323 T/h