First, an overview 
 XFTQ series gas turbine flow meter is a meter draw at home and abroad advanced technology optimized design, a combination of gas mechanics, fluid mechanics, electromagnetics, and other theories developed on their own set of temperature, pressure, flow sensors and intelligent flow totalizer in one of the new generation of high precision and high reliability of the gas-precision measurement instruments, with excellent low and high pressure metering performance, a variety of signal output and low sensitivity to disturbance of the fluid, widely used in natural gas, coal gas, liquefied petroleum gas , the measurement of light hydrocarbon gas and other gases. 
 Explosion of the product by the national product quality inspection departments at GB3836.2000 "Electrical apparatus for explosive gas atmospheres Part 1: General requirements", GB3836.2-2000 "Electrical apparatus for explosive gas atmospheres Part 2: Flameproof" d "" and GB3836.4-2000 "Electrical apparatus for explosive gas atmospheres Part 4: Intrinsic safety" i "" standard inspection, proof mark for the Exd Ⅱ BT4 (flameproof), Exia Ⅱ CT4 (intrinsically safe). Suitable for containing Ⅱ A, Ⅱ B, Ⅱ C Class T1 ~ T4 temperature classification of explosive gas mixtures of 0 (only intrinsically safe), 2 hazardous locations. 
 Second, product characteristics 
 ? Quality alloy turbine, with a steady flow and a higher resistance to corrosion 
 ? Import high-quality special bearings, long life 
 ? Isolated room measuring chamber and ventilation, to ensure the safety of the instrument 
 ? Can detect the measured gas temperature, pressure and flow rate, flow rate can be compensated automatically track and display the standard state (Pb = 101.325KPa, Tb = 29*K) the cumulative amount of gas volume; temperature and pressure values ??can be real-time query 
 ? Flow range (Qmax / Qmin ≥ 20:1), good repeatability, high accuracy (up to 1.0), pressure loss, low starting flow rate up to 0.6m3 / h 
 ? Intelligent instrument more non-linear correction factor 
 ? Built-in pressure, temperature sensors, safety performance, compact structure, beautiful appearance 
 ? Instrumentation and protection with explosion-proof, explosion-proof signs for Exd Ⅱ BT4, Exia Ⅱ CT4, degree of protection IP65 
 ? System, low-power operation, a 3.2V10AH lithium batteries can be used continuously for more than 3 years 
 ? Meter factor, the cumulative flow of power-down value is not lost decade 
 Third, the principle 
 When the fluid flow meter, in the inlet under the action of specific integration has been rectified rectifier and speed, as turbine blades and the fluid flow into a certain angle, then rotate the turbine produces torque, torque to overcome friction and fluid drag torque, the turbine started rotate. In a certain flow range, the turbine rotation is proportional to angular velocity and volume flow of fluid. According to the electromagnetic induction principle, the use of magnetic sensor signal from the coaxial rotating wheel and the volume of fluid flow induced proportional to the pulse signal, the signal amplification, filtering, shaping and temperature, the pressure sensor signals together into the Intelligent Flow Totalizer micro-processing unit for instrument operation and placing the total gas volume flow and directly displayed on the LCD screen 
 Fourth, the technical parameters: 
 4.1 Basic parameters: Table 1 
 Implementation of standards in the closed pipe flow measurement of gas - gas turbine flow meter (GB/T8940-2003)