General principles for electromagnetic flowmeter selection
(1) Whether the medium to be tested is a conductive liquid or slurry, thereby determining whether an electromagnetic flow meter is selected;
(2) The conductivity of the measured medium determines the type of electromagnetic flowmeter—whether it is high conductivity or low conductivity;
(3) The nominal diameter of the large, small and common flow process pipelines required by the process, determine whether the flow rate of the medium is at a more economical flow point, whether the pipeline needs to be reduced, and then determine the diameter of the flowmeter;
(4) Determine whether to use an integrated or split flowmeter, and the degree of protection of the flowmeter, etc., based on the layout of the process piping.
(5) Selecting the electrode type according to whether the measured medium is easy to crystallize or crusting;
(6) selecting an electrode material according to the corrosiveness of the measured medium;
(7) The corrosiveness, wear and temperature of the measured medium determine the lining material to be used;
(8) The high working pressure of the measured medium determines the nominal pressure of the flow meter;
(9) The insulation of the process piping determines the type of grounding ring.
Advantages of turbine flow meters
The pressure loss is small, and the impeller has anti-corrosion function;
1.Adopt advanced ultra-low power single-chip microcomputer technology, the whole machine has strong functions, low power consumption and superior performance.
2.Intelligent flow display with nonlinear accuracy compensation. Correction formula accuracy is better than ±0.02%
3.The meter factor can be set online by button and can be displayed on the LCD screen. The LCD screen is intuitive and clear, and the reliability is strong.
4.EEPROM is used to accumulate the flow and the meter coefficient is powered down. The protection time is more than 10 years.
5.Using high-performance MCU central processing unit to complete data acquisition and processing display output, cumulative flow instantaneous flow
6.The screen displays a convenient man-machine interface for data transfer in standard 485 format.
7.Fully hard alloy (tungsten carbide) shielded cantilever beam structure bearing, integrating rotary bearing and pressure bearing, greatly improving bearing life and working in medium with a small amount of sediment and dirt.
8.It adopts 1Cr18Ni9Ti all stainless steel structure (the turbine adopts 2Cr13) and has good anti-corrosion performance.
9.Easy to maintain, self-rectifying structure, small and light, simple structure, which can be combined in a short time.
10.Internal cleaning is simple.
11.Strong anti-magnetic interference and vibration capability, reliable performance and long life
12.The lower limit flow rate is low and the measuring range is wide.
13.The on-site display type LCD screen is clear and intuitive, with low power consumption. The 3V lithium battery can be operated continuously for more than 5 years.
Corrosion resistant, suitable for acid and alkali solutions
Steam vortex flowmeter measurement requirements
Keywords: steam vortex flowmeter, saturated steam vortex flowmeter, superheated steam vortex flowmeter
What should I pay attention to when measuring vortex flowmeter? What is the best way to measure steam installation by vortex flowmeter? Can vortex flowmeters be used for steam metering? The vortex flowmeters are evaluated for their measurement performance under single-phase flow conditions. There is currently no single-phase flowmeter for measuring the system variation of two-phase flow. However, the two-phase flow exists objectively, and its influence on flow measurement is unavoidable. Despite the difficulties, people are still trying to study the mechanism of its influence on flow measurement, and take corresponding countermeasures to improve the accuracy of flow measurement.
First, steam flow measurement difficulties
During long-distance transportation, dry steam will partially condense due to heat loss, resulting in reduced steam dryness and become wet steam. The gas-liquid two-phase flow structure in the horizontal pipe is related to the gas-liquid two-phase volume ratio and the flow velocity. In the steam pipe, since the volume ratio of the condensed water in the wet steam is small, the drain pipe drawn from the bottom of the horizontal pipe is made. , can receive a good hydrophobic effect. When the flow rate is particularly high, it will also behave as a circular flow, that is, there is a liquid film on the pipe wall, and the central part of the pipe is a gas core with droplets. Due to the influence of gravity during horizontal flow, the lower liquid film is higher than the upper pipe. The thickness of the wall, in the vertical ascending pipeline, the basic structure of the gas-liquid two-phase flow has a fine bubble flow structure, a bullet-like flow structure, a block flow structure, a ring-shaped flow structure with fibers, and an annular flow structure.