Project Background
A petrochemical park supplies steam centrally to multiple chemical plants. As a trade settlement medium, steam metering accuracy directly affects the economic interests of all parties. The original orifice plate flowmeters had high maintenance workload, severe accuracy drift, and frequent trade disputes. The park decided to upgrade the metering system, requiring an accuracy of ±1.0%.
Customer Challenges
1. Wide steam condition fluctuations: pressure 0.5-1.2MPa, temperature 180-250°C, wide flow range (3:1~10:1), requiring wide turndown ratio and high accuracy. 2. Strong on-site vibration interference, traditional vortex meters are susceptible. 3. Trade metering requires long-term stability and must pass metrological verification. 4. 80 sets of meters distributed across different pipe diameters (DN50-DN200) need unified management.
Solution
Adopted Jiangsu SIENCUN Instrument Co., Ltd. LUGB series vortex flowmeters, paired with platinum RTD and pressure transmitter for temperature and pressure compensation. The vortex meter uses a capacitive detection probe, offering better vibration resistance than traditional piezoelectric types; the meter body accuracy is ±0.5%, and the compensated system accuracy is ±1.0%. Each meter was calibrated on a steam flow standard facility before delivery to ensure traceability. An intelligent totalizer performs real-time calculation of temperature, pressure, and flow, and stores trade settlement data.
Implementation Process
1. Site survey: confirmed pipe diameters, installation positions, and straight pipe lengths (ensuring 10D upstream and 5D downstream). 2. Custom production: selected high-temperature and high-pressure resistant materials (304 stainless steel, rated 350°C). 3. Installation and commissioning: flanged installation, strict alignment, avoiding gasket protrusion into the flow path. 4. System integration: interfaced with the park's DCS for remote data transmission and centralized monitoring. 5. Metrological verification: third-party on-site verification, all 80 meters passed, maximum error -0.8% to +0.9%.
Results
1. Steam metering accuracy stable within ±1.0%, trade disputes reduced by 90%. 2. Wide turndown ratio (1:15) adapts to varying load conditions. 3. Excellent vibration resistance, no false alarms due to vibration. 4. Maintenance reduced by 80%, no need for periodic orifice cleaning. 5. Annual steam loss reduced by about 2%, saving the park over one million yuan.