What is a flowmeter ? Simply a device that can monitor and measure the actual amount of ‘product’ being sent through it. Typically flowmeters in industry are used for monitoring use of water, chemicals, ingredients, etc.
Text of Compressed Air Flowmeters
1. An Introduction to Testo Compressed Air Flowmeters -6440 and 6446/6447 series
2. What / why / how ? What is a flowmeter ? : Simply a device that can monitor and measure the actual amount of product being sent through it. Typically flowmeters in industry are used for monitoring use of water, chemicals, ingredients, etc. Some flowmeters have a basic indicator built in to show value, more sophisticated will have outputs that can be fed into measurement & control systems. Why use a flowmeter ? : To accurately determine how much of something is being used for cost/performance reasons. Often they are used as part of a overall process plant control system. How does a flowmeter work ? : There are many technologies used depending upon the product to be monitored and its physical variables, common types for airflow would be insertion pitot, turbine/vane, variable area, venturi, etc. All technologies have good/bad points it is usually a case of matching the best technology to the required application.Testo Limited2/2 3. Testo compressed air flowmeters basic info We have a range of flowmeters marketed for use within the compressed air industry these have been designed around specific requirements found within compressed air systems, however with a correction factor applied they can be used for nitrogen (N2), carbon dioxide (CO2), and argon (Ar). Why use a flowmeter to monitor compressed air ? : Unlike all other utilities used in a factory or production line, compressed air is usually NOT metered, so usage is unknown. The compressed air comes from having a compressor somewhere in the facility, and this compressor is using electricity. Also you may have leakage within the air system. Compressor systems typically represent between 5%-40% of total facility energy consumption. Surveys have found that on average 20% of the compressed air produced on a system is wasted through leakage. At 7 bar (100psi) : 3mm hole = 12 l/s = 3,260 per annum. 6mm hole = 47 l/s = 12,770 per annum. A 2 l/s leak is to small to hear but would still cost 590 annually.Testo Limited 3/2 4. Typical compressed air system Diagram below shows a basic schematic for a typical industrial compressed air system. The flowmeter must be placed after the dryer so that the air flowing through is as dry and as clean as possible.Note the amount of condensate drains in a typical system this is due to the fact thatwhen ambient air is compressed there is a huge amount of moisture generated. Thisneeds to be removed by a dryer system otherwise this wet air will destroydownstream equipment. Testo also make specialised sensors for measuring tracehumidity in compressed air systems.Testo Limited 4/2 5. Testo compressed air flowmeters basic info What can we offer : 2 main versions of product. 6441 6444 suitable for most small bore pipework. 6446/6447 for larger plant pipework and also special feature of replacement sensor whilst system is under pressure. Common process conditions for both series are : 0 to 60C 16 bar max (PN16)