The key to precise metering and control of gases is ensuring that the equipment installed to perform the task is accurate, reliable and capable of integrating with other system controls. Bürkert Fluid Control Systems has perfected the art of gas handling, with a range of monitoring and control products that has now been extended by the introduction of two new gas flowmeters.
Bürkert has considerable experience and expertise in gas handling technology and has developed a number of products that can be applied to a wide range of gas applications. The latest additions are the Type 8007 and Type 8008 flowmeters, which are designed for measuring especially large flow rates.
The main issue with measuring the flow of gas is that the accuracy can be reduced by changes in temperature and pressure. By using the calorimetric principle of flow measurement, the accuracy of these new flowmeters can be assured since it is unaffected by changes in temperature and pressure. Both of the new products use this method of measurement which requires no moving parts, thereby not only increasing the overall reliability but also providing relatively high accuracy at low flow rates. Both meters provide a 4-20mA analogue output signal which can be used to control a huge range of components such as process control valves and solenoid valves either directly or via a PLC.
The Type 8008 is designed for pipe sizes up to 2" and can be used to monitor air supplies as well as for measuring other gases. The flowmeter has an integral display which can be configured to display the measured flow in a variety of units as well as maintaining a value for the total volume measured. As standard, the maximum flow is 825 Nm3/h, with special flow ranges available on request, while the maximum operating pressure is 16 bar.
The Type 8007 flowmeter can be used in pipe diameters ranging from 0.5" up to 12" (DN300) and it features a depth scale that ensures that the sensor is correctly positioned within the pipe. It is available in three versions: Basic, Extended and Maximum, each calibrated for a velocity range, 85.2m/s, 170.1m/s and 206m/s respectively. The capacity of this product type ranges from 41 Nm3/h for 0.5" pipe up to 44,030 Nm3/h for a Maximum version installed in a 12" pipe, with a maximum operating pressure of 50 bar.
Clearly, to ensure the accuracy levels specified, it is essential that the flowmeter is correctly installed and that it is located in an undisturbed gas stream. This is determined by the design of the pipework both upstream and downstream of the sensor location; precise details can be found in the product datasheets, which can be downloaded from the Bürkert website.
