wt-b thermal gas mass flow meter

Thread Content

This post was last edited by suntey on 2010-11-6 at 14:06. ■ Gas measurement experts from the professional manufacturing technology industry ■ Imported sensors using German patented technology ■ Products manufactured exclusively in China based on the principles of transverse power and transverse temperature difference. Detailed information: WT-B series thermal gas mass flow meters ■ Proprietary flow data model algorithm； Fuzzy theory algorithm for controlling temperature and humidity ； High-performance intelligent microprocessors and analog-to-digital, digital-to-analog conversion chips ； Wide range ratio of 1000:1 ； Large diameter, low flow rate, negligible pressure loss ； Direct measurement of mass flow rate, without the need for temperature and pressure compensation ； Low-flow measurement is highly sensitive. The requirement for the straight pipe section is not high, 1-2D. I. Product Applications:
• Measurement of compressed air in factories
• Measurement of natural gas
• Measurement of fuel and air supply in boilers
• Measurement of aeration in wastewater treatment
• Measurement of flame gases
• Measurement of liquefied gas and biogas
• Measurement of hydrogen
• Measurement of gas supply in steel mills
• Measurement of ammonia in fertilizer plants
• Measurement of coke oven gas in coking plants
• Measurement of blast furnace gas in ironmaking plants
• Measurement of primary and secondary air in power plant blast furnaces
• Control of the powder/gas ratio during coal powder combustion
• Monitoring of SO2 and NOX emissions from flue gases
• Measurement of various gas flows in fuel cell factories
• Control of hot gas flow emitted by vertical grinding mills in the cement industry
• Control of gases such as hydrogen, oxygen, and nitrogen in heat treatment and quenching furnaces
• Measurement and control of gases used in heating furnaces in steel rolling mills (such as blast furnace gas, coking gas, natural gas, etc.).

II. Product Features:
• Uses patented platinum RTD sensors with extremely high stability
• Features a proprietary “balanced structure packaging” design that enables self-compensation for medium temperature changes
• Proprietary algorithms ensure high linearity, high repeatability, and high precision
• Wide measurement range of 1000:1, with the possibility of expansion based on user requirements
• Minimal pressure loss, practically negligible
• Can measure flow rates as low as zero; resolution of 0.001 m/s
• Capable of measuring low flow rates in large-diameter pipes
• Enables multi-point flow measurement
• Vibration effects have minimal impact
• Low requirements for straight pipe sections – 1–2D is sufficient
• Can measure flow rate in both directions, regardless of medium temperature or pressure
• Proprietary high-temperature algorithm allows operation at temperatures up to 510°C
• High-precision measurement thanks to advanced humidity compensation algorithms
• 12-point dynamic correction for flow signal input, along with 10 built-in correction points
• One-button zeroing function
• Online dynamic calibration of current/voltage outputs
• Wide-screen LCD display showing instantaneous and cumulative flow rates directly
• Not sensitive to small particles such as dust
• Easy maintenance due to possible online installation/removal without interrupting flow
• Different product signals available for various industries (flue gases, blast furnace gas, coke oven gas, vehicle exhaust, etc.).

III. Principle of Operation:
The wt-b series of flow meters/flow switches are flow measurement devices based on the principle of thermal diffusion. In other words, when a fluid flows over a heated object, the amount of heat lost by that object is proportional to the flow rate of the fluid. Specifically, the sensor of this flow meter consists of two standard-grade RTDs: one is used as a heat source, and the other is used to measure the temperature of the fluid. As the fluid flows through, the temperature difference between the two is related to the flow rate in a non-linear manner, and the instrument is able to convert this relationship into a linear output that represents the flow rate. There are two design approaches for flowmeters manufactured using the principle of thermal diffusion: one is based on the principle of a constant temperature difference ； The second is based on the constant power principle. Based on a common data model: P/△T = A + B(Q) N ^ –1. Here: P – dissipation power, △T – temperature difference between the two sensors, A and B are coefficients related to the thermal properties of the gas. Principle of constant temperature difference: With △T remaining constant, the dissipation power P increases in an exponential manner with the flow rate Q of the fluid. Constant power principle: The dissipated power remains constant, and the temperature difference ΔT decreases in an exponential manner as a function of the fluid flow rate Q. IV. Performance specifications: • Measurement range: 0–120 m/s (at 20 ℃, 101.33 KPa) • Accuracy: ±1% of the reading ±0.5% of the full scale • Repeatability: 0.2% of the full scale • Operating temperature range: –40 ℃ to 85 ℃ (without display); –30 ℃ to 70 ℃ (with display); humidity less than 90% RH • Medium temperature range: –40 ℃ to 100 ℃, –40 ℃ to 200 ℃; –40 ℃ to 450℃ ； -40 ℃ - 510 ℃ • Analog output: Flow rate: 4-20mADC ； Temperature: 4-20mADC • Output of cumulative pulse count • Supports 12 levels of nonlinear correction; 10 levels of nonlinear correction are built-in • Communication: Serial output via RS232/RS485 • Power supply: ； 24VDC/600mA ； 220VAC/2W ； 110VAC/3W • Upper and lower limit output relays • Seven-digit instantaneous flow display, eight-digit cumulative flow • One-key reset function • Online current output calibration • Large LCD display • Process pressure :