# Pitot Tube Anemometer + Differential Manometer calibration service

With the aim of serving customers with the best after-sales services, EMIN Vietnam has established the Equipment Inspection - Calibration - Repair Service Center. With the support from numerous equipment manufacturers in the world, EMIN Vietnam possesses well-prepared calibrating instruments. EMIN Vietnam has successfully repaired and calibrated specialized equipment in Vietnam, ensuring the quickness, effectiveness and convenience for customers. Only few technical trading company in Vietnam do possess this technical capacity including EMIN Vietnam.

>> Tube Pressure Meter by Pitot Tube
The pitot tube is named after Henri Pitot, who used a glass tube to measure the flow velocity of a river in France in 1700. The pitot tube is a simple device with no moving parts used to measure flow velocity.

>> Other information
- The pitot tube is a common flowmeter. The figure below shows the basic behavior of a pitot tube, where pressure is generated by the velocity of the fluid in a tube opposite the flow. This dynamic pressure is compared with the reference pressure (static pressure) in the pipe, and this velocity can be determined with a simple formula.

Because of the simplicity of the pitot tube (as shown in the figure) only sampling at one point, and because the flow rate (flow velocity) is different at each point in the pipeline, the exact position of the flow is It is therefore very important to correct these points we use a medium pitot tube.
Note the square root relationship between velocity and pressure drop (see formula below)
This limits accuracy to a small range

Here:
u1 = Velocity of the fluid in the pipeline
Δp = Dynamic pressure - Static pressure
ρ = Density of fluid
There are a few practical limitations in using a pitot tube
* If the velocity is low, the differential pressure will be very small and the probe can hardly measure accurately. Errors can be very large in measurements. Hence the pitot tube cannot operate at too low a speed.
* If the passing velocity is large (ultrasonic) It violates Bernoulli's assumptions and the measurement will not be correct. In front of the tube, a shock wave appears to change the total pressure, which can be corrected to the high speed pitot tube like an airplane.
* If the pipe is clogged or squeezed, the pressure at the pressure probe will not match the dynamic and static pressure in the pipeline, so it cannot measure the velocity of the flow properly at this time.

>> Medium pitot tube
* The average pitot tube (as shown below) is developed with a number of points for measuring the dynamic pressure on the pipe in the horizontal direction then the average value of the dynamic pressure is then compared with the static pressure. in the pipeline. from which the flow velocity is calculated.
>> Advantages of the pitot tube
* Less obstructing the flow
* Less money.
* Simple type flowmeter can be used for many pipes of different sizes.
>> Disadvantages of pitot tube:
* Limit ratio is small because of the square 2 relationship between pressure and velocity.
* If the fluid is liquid, the measuring holes or pipes may be blocked. To eliminate this, some models are installed horizontally
* The position in the pipeline must be correct
>> Application of the pitot tube:
* Used in the measurement of flow rate, flow rate

For further information about calibration service, visit our website at: https://emin.vn/en_US/calibration-inspection-service-985/pc.html