Simple Structure Clean Liquid Wedge Flow Meter With Two Wire 4~20mADC Signal Output
Wedge-shaped flowmeter is new style differential pressure flow instrument of our company, which is consist of flow sensor and differential pressure transmitter. It has already made up the gap that domestic measuring domain have no flowmeter that can measure city gas with large-scale change(flow change can be dozens of times with the change of time) and natural gas; Which has solved the flow measuring difficulty of pix, pitch, residue oil, paraffinic oil and all kinds of mediums with high viscosity. Besides, it is also widely used in measuring those enterprises with strong causticity, those saturated or oversaturated acid, alkaline, and saline liquid will separate out crystallization with the change of temperature.
LX wedge-shaped flowmeter with simple structure, reliable property, easy installation, competitive price and low cost to be maintained, and has been widely used in measuring clean liquid, fluid with high viscosity, corrosive fluid, slurry, kinds of gas---air, steam, smudgy gas and natural gas etc. It is also can be used under this situation---Reynolds number of pipe is 500 and viscosity is 500 mpa.s.
1. High accuracy, good stability, excellent repeatability. Measuring tolerance: +/-0.5F.S; Long-term stability: +/-0.1%F.S/Y.
2.Simple structure, reliable stability, long-term use, five-years maintenance-free. Wedge-shaped flow sensor has special structure, differential pressure with excellent property, through serious test and correction, its life can be ten years.
3.Wide measuring range. Rate of measuring range normally is 1:25, can be 1:33. After changing the differential pressure, the rate can be more than1:100.
4.Immense application. Not only can be used for single-phase liquid, but also can be used for gas-liquid, gas-solid and liquid-solid double-phase fluid. The minimum Reynolds number can be 300, maximum can be 1x107.
5.Anti-adhesive, no deposition, non-clogging. The measuring pipe of wedge-shaped sensor and the design of anti-adhesive structure, prevent silt, powder, suspended solids and fiber from adhering and piling to the pipe of sensor, and avoiding the corroding measuring pipe, thus ensure the long-term accuracy of measuring pipe.
5.Integrated. Integrated installation---Wedge-shaped sensor, three-valve set and differential pressure transmitter. Leaving out guide-pressure pipe, valve, pipe fitting, making the system more simple, improving the accuracy greatly.
6.Intelligent. Customer can set and configurate the parameter via HART or
other communication modes. To adjust the differential pressure according to the change of medium, widening the measuring range. The intelligent type can realize the measure of multiple parameters(Differential pressure, volume flow, quality flow, pressure, temperature), realizing completely temperature compensation, directly outputting accuracy signal.
7. Less requirement on straight pipe installation. Can effectively avoid the uncertainty of additional measure.
8. Less pressure loss, saving resource.
|Accuracy class||0.5(0.2,0.3,0.4 customize)|
|Long-term stability||± 0.2% F.S / Y|
|Medium||All kinds of liquid, gas and steam|
|Min flow rate||0.01m/s|
|Measuring range||Normal: 1:25, max:1:33|
About 1/5 of measuring differential pressure
|Reynolds number scope||Upper limit 500, upper limit≦1×107|
|Medium viscosity||500mpa.s or more|
|Working pressure scope||-0.1~42MPa|
|Working temperature scope||-160℃~450℃(max 700℃)|
|Pipe size||DN10mm~DN1200mm(max 2500mm)|
|Wedge ratio h/d||0.2, 0.3,0.4,0.5|
Differential pressure transmitter power
|Differential pressure transmitter output||4mA ~ 20mA DC(Hart)|
LX Wedge flowmeter can measure medium as follows:
1.gas:coal gas, CNG(High humidity of natural gas,Non clean natural gas),air(air with water,rigid granules,suspended solid)
2.Steam: saturated steam, superheated steam
3.Liquid: oil, seriflux, water(pure water, sewage, industrial sewage ), all kinds of aqueous solution.
Flowmeter measuring system
Lx wedge flowmeter system has no compensation, pressure compensation, and temperature compensation.
1. No compensation type consists of sensor, DP transmitter, 3-valve manifold and Calculation of flow machine. Except the sensor, others are optional item.
2. pressure compensation type consists of sensor, DP transmitter, 3-valve manifold , pressure transmitter and Calculation of flow machine.
3. temperature compensation consists of sensor, DP transmitter, 3-valve manifold , temperature transmitter, pressure transmitter, and Calculation of flow machine.
This item can realize temperature and pressure compensation, directly output of accuracy flow as integrated type utilized multiple parameter transmitter, which can Set of differential pressure, pressure, temperature as a whole.
The basic measuring principle of LX wedge-shaped flowmeter is totally same as orifice plate and traditional venturi ---flow measuring instruments of differential pressure style, which are based on law of conservation of energy---Bernoulli equation and flow continuity equation.
The detection part of wedge-shaped flowmeter is wedge-shaped orifice plate; it is a V-shaped throttling element, and its round angelus parietal is adown, which in favor of avoiding viscous flow at upstream of throttling element when fluid with suspended particle(powder, silt and other solid particle) and liquid with high viscosity flow through. Which can also prevent the solid particle and dope from accumulating at the upstream and downstream of throttling element.When the square root of the pressure produced by fluid flowing through wedge-shaped chunk is in direct proportion to quality flow or volume flow, the rate of different arch height H and pipe diameter D(wedged-shaped rate H/D) to confirm measuring range. LX wedge-shaped flowmeter can solve your most difficult measuring problem, and can ensure reliable measuring result. Thus ensure the sensor keeping the +/-0.1FS%Y stability.
Wedge and connection part is made of stainless steel(1Cr18Ni9Ti /304/316) and shell(flange/pipe) is made of carbon steel or stainless steel and can be used for non corrosive medium under 400℃. When the temperature is more than 400℃, customer should choose heat-resisting steel depending on working temperature,Oxidation of medium and corrosion. While it is -20~190℃, customer should choose 1Cr18Ni9Ti Low temperature resistance material. In addition, customer should confirm with manufacturer if the medium is corrosive.
Generally adopt normal thread pressure tapping for measurement of differential pressure. Namely open a hole in the measuring pipe and connect pressure tap to connecting pipe. It is not suitable for occasion of guide pressure directly for transmission flange taps, such as viscosity oil, dirty liquid. Installation size for sensor of transmission pressure tap depends on sensor model specification.
Horizontal Installation requirement
1.The best installation angle of pressure tap should be 0°and 180°when the medium is liquid or steam.If not, customer should choose angle between 0°~45° and 135°~180°, but DP transmitter must be installed vertically on 3-valve manifold.
2.The best installation angle of pressure tap should be 270° when the medium is gas.If not, customer should choose angle between 210°~270°and 270°~330°, but DP transmitter must be installed horizontally on 3-valve manifold.
vertical Installation requirement
1, DP transmitter should be installed vertically on 3-valve manifold, which is at the side of lower pressure tap, while the medium is steam and liquid.
2, DP transmitter should be installed horizontally on 3-valve manifold ,which is at the side of upper pressure tap, while the medium is gas.