Ultrasonic Flow Meter is a flow meter whose way of working to measure or calculate the flow speed of a fluid by using ultra sound for flow rate accumulation.
Pengertian Ultrasonic Flow Meter
With the known flow speed, it can be calculated flow rate by knowing the area of support of a flow path. Ultrasonic Flow Meter is widely known as a flow meter whose installation system uses a non-contact system where the sensor or transducer does not contact directly with the fluid. Because the way the installation is non contact or clamp on, ultrasonic flow meters are known as portable flow meters.
Likewise for ultrasonic insertion flowmeter installation system the way the installer is to perforate the pipe which is then installed fittings and ultrasonic sensors or transducers are inserted in fittings and pipes that have been in the hole. From the sensor by using cable is forwarded into the ultrasonic transmitter to calculate the velocity and flow rate of fluid in the pipe.
Working Principles of Ultrasonic Flow Meter
Construction of this type of flow meter can be done using upstream and downstream transducers, sensor pipes and reflectors. The working principle of ultrasonic flow meters is, using sound waves to complete the speed of the liquid inside the pipe. There are two conditions inside the pipe as it does not flow and flow. Under the first condition, the frequency of ultrasonic waves is transmitted into the pipe and its indication of a similar fluid. Under the second condition, the frequency of the reflected wave is different due to the Doppler Effect.
Whenever a liquid flows in a pipe quickly, the frequency shift can be increased linearly. The transmitter processes the signal from the wave and its reflection determines the rate of flow. The transit timer sends & receives ultrasonic waves in both directions inside the pipe. Under no-flow conditions, the time it takes to flow between upstream and downstream between transducers is the same.
Under these two flowing conditions, the waves upstream will flow at speeds smaller than downstream waves. As fluids flow faster, the difference between up and down times increases. Upstream & downstream time is processed by the transmitter to determine the flow rate.
Types of Ultrasonic Flow Meter Installations
- Portable Ultrasonic flow meter
- Clamp on fix ultrasonic flow meter
- In Line Ultrasonic Flow Meter
- Insertion Ultrasonic Flow Meter
- Open Channel Ultrasonic Flow Meter
Of the type of ultrasonic flow meter based on the way of installation that is most preferred is the type of installation clamp on because it is very suitable in application to very large pipes or on pipes that they do not want to disturb the production process.
Also Read: Use of Ultrasonic Flowmeters in Wastewater Treatment
In Line & Insertion
In accordance with its development, ultrasonic flow meters are also in production with in line flow meter installation system and also insertion ultrasonic flow meter. For the type of in line ultrasonic flow meter ultrasonic sensor or transducer is permanently framed on the flow tube which then by using kable is forwarded into an ultrasonic transmitter or flow computer. For this type of ultrasonic flow meter the type of connection or how to install it by cutting pipes that are then installed flange or made drat.
While fix clamp on ultrasonic flow meter is widely used to know the volume or flow rate or for control flow rate of closed flow system. Because it is used for continyu flow rate monitoring, the power used usually uses AC and DC power.
Portable Flow Meter
Portable flow meters began to be famous when the known flow meter type ultrasonic where the way of use and installation is quite easy and fast and can be below where.
Portable flowmeter uses a type of clamp on flow meter where the sensor or often referred to as ultrasonic transducer is enough in the clamp on the outer surface of the pipe, because the process of insatlation without cutting pipes or perforating pipes then the installation cost of the flow meter clamp on is very cheap and fast.
For the type of portable flow meter is usually equipped with a vaik data logger internally and externally and for power because of its portable nature usually uses a battery that can be charged and generally the battery is able to work at a long time above 5 hours.
Clamp On
Flow meter clamp on ultrasonic is a type of flow meter that works using ultra sound and the way it is installed is enough with clamp on the surface of the pipe. What is meant by the way of clamp on installation is when doing the installation we do not need to cut the pipe or perforate the pipe.
By cutting pipes or perforating pipes, it will hamper the production process because the flow of water must be turned off. In addition, the cost to cut or perforate pipes followed by conection welding, in the form of flange or fittings is not cheap and takes a fairly decent time. Imagine if we had to install a water flow meter on a pipe with a diameter above 12 inches, it can be ascertained that the price of flange, gasket, cutting and welding costs can be ascertained very expensive.
Also Read: Ultrasonic Flow Meter for Small Flow Without Using a Pump
Therefore there are many engineers to suggest using the type of flow meter insertion type magnetic flow meter or its type that tends to be more economical when compared to the type in line. Because the way the installation is enough to perforate the pipe continued by welding on fiiting as a place or stand insert (insert) sensor into the pipe to detect the speed of water flow in the pipe.
This type of flow meter clamp on ultrasonic consists of a sensor or transducer and a flow computer or ultrasonic transmitter. The function of ultrasonic transducer is as a sensor to detoxify the speed of water flow in the pipe that is forwarded to the ultrasonic flow transmitter which is then processed by calculating the calculation of distance to the time difference from the emission of ultrasonic sura waves so that it can velocity from the siran in the pipe.
Advantages of using Flow Meter Clamp on ultrasonic:
- There is no barrier on the flow trajectory, so there is no pressure drop.
- There are no moving parts, so no parts wear out that cause low maintenance costs.
- Multi sensor models have higher accuracy
- It can be used to measure corrosive fluid flow and slurry.
- There is a type of sensor that can measure pipe dimeters of size DN15 – DN6000
- If applied to large pipe sizes above 4 inches will be more economical compared to other types of flowmeters.
- Installation costs are very cheap especially if installed on large pipes.
- No need to stop the flow process in the pipe or no need to turn off the pump
- It can be operated on all types of pipe materials (carbon steel, PVC, HDPE, SUS, etc.) and all types of homogeneous liquids.
- Can be operated on wastewater and dirty water with a maximum of 12% solid particles
- Can be installed on streams with low flow velocity up to 0.03 m/s
- Has a fairly good accuracy of 1% – 2%
- In additional available external data logger by using SD card
- Analaog ouput 4-20mA, Pulse, relay and communication RS485
- Available sensor with IP68 class (water proof)
In Line Ultrasonic Flow meter
This type that is widely circulated is used in the industrial world so far more using the type of flowmeter whose installation uses a clamp on system that is an installation that does not need to cut pipes or perforate pipes. Therefore, the assumption of most enginners if thrust with this type is always indented clamp on flow meter.
Though this is the only flow meter that has characteristics in doing installation does not need to be done by stopping the flow in the pipe for too long and identified without having to close the valve or turn off the pump. Even though ultrasonic flow meters there are also those who use the installation system must turn off the pump or close the valve and do pipe muscle. This type of installation must do pipe cutting and continue by installing flange or making threads named by the term InLine as in the picture below.
Also Read: Types of Fluids and Flowmeter Characteristics
Advantages and Disadvantages of Ultrasonic Flow Meter
Here are the advantages and disadvantages of Ultrasonic Flow Meter, let’s look at:
Advantages
- It does not block the flow path of the liquid.
- O/p meters are different for density, viscosity &temperature of liquids.
- Fluid flow is two-way.
- The dynamic response of this meter is good.
- The output of this meter is in analog form
- Energy conservation
- It is suitable for large quality flow measurements
- Very useful for adjusting and maintaining
- Flexibility is good.
- No contact with liquids
- There is no risk of leakage.
- No moving parts, loss of pressure
- High accuracy
Disadvantages
- Quite expensive compared to other mechanical flow meters.
- Design that is too complicated
- The sensor part of this meter is expensive.
- This meter is complicated compared to other meters, so it requires specialists to maintain and repair these meters.
- Cannot measure rusty cement or concrete pipes.
- It doesn’t work after a pipe contains a hole or bubble in it
- Unable to measure cement/concrete pipes or pipes with such a layer of material
How to Install Ultrasonic Flow Meter
The most popular and sought-after method of ultrasonic flowmeter installation by instrumentation equipment users is a type of clamp on installation. There are 2 types of flow meters clamp on type, namely the type of portable ultrasonic flow meter and wall monting ultrasonic flow meter. For the type of flow meter clamp on can be used on pipe sizes from DN15 to DN6000, with some transducer sizes adjusted to the diameter of the pipe. Another advantage of this clamp on flow meter is that it can be operated on all types of pipe materials and all types of homogeneous liquids.
The way to install a utrasonic clamp flowmeter on is very easy and fast, with the first step is to collect pipe and liquid data as variables that must be entered into ultrasonic flow transmitter. When the data entered is in accordance with the actual it will be obtained a good ultrasound power.
In addition to the diameter of the pipe is usually somewhat difficult is the data thickness of the pipe, because the average user does not have a thickness gauge. But we can enter the thickness of the pipe based on the table of pipe dimensions that isa downloaded through google. When we need an output from an ultrasonic transmitter that can be inserted into the plc or other, do not forget to set the output parameters, and this is usually based on the flow rate or pulse.
Also Read: Ultrasonic Portable Flow Meter to Check Machine Cooling System
Thus the Article “Ultrasonic Flow Meter: Working Principles, Types, and Advantages” Hopefully can help and answer about related articles, hopefully useful.