How to choose a good waist wheel flow meter? Let's talk about it.

Waist wheel flow meter must choose a good brand to use the convenience. In general, the selection of type should be considered from these three points, that is, the way of flow sampling device and the type and specification of measuring instrument should be determined according to the property and flow situation of the measured flow body, the selection should be completely in line with the instrument conditions provided by the process, and the precision grade and economy should be considered.

Ⅰ.The type and specification of the waist wheel flow meter are determined according to the property and flow situation of the measured flow body.

The property and flow condition of the fluid determine the form and specification of the flowmeter. First, the selection should consider several key physical and chemical properties of the fluid: the state of the fluid (solid gas or liquid), the conductivity of the fluid, the chemical corrosion of the fluid, and the viscosity of the fluid.Second, we should fully understand the application scope of various flow meters.The physical and chemical properties of the fluid should be taken into account when selecting the type.The fluid in solid state is usually dust or mass strong, and only three types of flowmeter are chosen: impulse flowmeter, belt weigh and track scale.The flow meter forms of liquid and gaseous fluid are more. Generally, flow meters have series and models specially used for gas measurement. For example, the coriolis force mass flowmeter we use has series models specially used for gas measurement.In the case of poor liquid condition, it is better to select electromagnetic flowmeter under the condition of non-exhaling corrosion, conduction and solid particles.The flow meters adapted to high viscosity mainly includeoval gear flow meter, waist wheel flow meter, scraper flow meter, target type flow meter, wedge type flow meter, etc.Finally, in the selection of corrosive fluid, attention should be paid to the selection of liquid material for the flowmeter. For example, when the electromagnetic flowmeter is used to measure hydrochloric acid liquid, the electrode must use tantalum electrode, otherwise the electrode will be easily corroded away.

Ⅱ.The choice of waist wheel flowmeter should take full account of the table conditions provided by the process.

First of all, the static pressure and temperature of the medium should be taken into consideration. The static pressure and temperature resistance of the flow meter are also an important link to guarantee the service life and accuracy of the meter. The static pressure of the meter, namely the pressure resistance, should be slightly higher than the working pressure of the medium under test.

Secondly, the choice of range range, mainly the upper limit of scale.Select small, easy to overload and damage the meter;It's a big one, and it's going to get in the way of measuring accuracy.The national standard stipulates that the maximum flow shall not exceed 95% of the full scale;The normal flow rate is 70% ~ 85% of full scale.Minimum flow is not less than 30% of full scale.Finally, the most important instrument conditions are process pipe diameter. Some flowmeters do not have large diameter, and some large-diameter flowmeters are very expensive. At present, flow meters suitable for large pipe diameter include flute-shaped constant speed tube, plug vortex, plug turbine,electromagnetic flowmeter,venturi tube andultrasonic flowmeter.

Ⅲ.Consider the accuracy grade and economy of the waist wheel flowmeter.

The accuracy grade of the flowmeter should conform to the provisions of the state economic commission [1983] no. 244 document 《requirements on the accuracy of energy measuring instruments》.Generally speaking, the places with high precision requirements mainly include raw material measurement of incoming plant and incoming production equipment, finished product measurement of outgoing plant and ex-factory sales, raw material measurement of technological formula and expensive material measurement.For the flow rate of the production equipment that only makes general reference, the low-price glass rotor, metal rotor and other inexpensive flowmeters are usually selected.The gas (air, nitrogen, steam) of utility engineering in production usually adopts vortex flowmeter, and the water mainly USES electromagnetic flowmeter. These two choices are both economical and accurate.