Mass-View® is best technology for hospitals and life sciences

Citation

(2009), "Mass-View® is best technology for hospitals and life sciences", Industrial Lubrication and Tribology, Vol. 61 No. 2. https://doi.org/10.1108/ilt.2009.01861bad.002

Mass-View® is best technology for hospitals and life sciences

Mass-View^® is best technology for hospitals and life sciences

Article Type: New products From: Industrial Lubrication and Tribology, Volume 61, Issue 2

Variable area (VA) flowmeters or rotameters are relatively low cost and simple to install, easy to read and maintain, require little or no energy and offer reasonable levels of accuracy and repeatability, which is why the technology is so widely used and trusted for gas and air flow measurement. Yet, says Cambridge-based Bronkhorst UK, for many applications, particularly in the Life Sciences and Medicine, where precision, rangeability, accountability and safety are critical, this centuries-old flowmeter principle no longer measures up. That is why Bronkhorst has developed a high technology replacement for the venerable VA meter, the Mass-View^® (Figure 1) which offers virtually the same configuration and characteristics, but with the extreme accuracy and integrity of direct thermal mass flow measurement, a digital bar graph of actual gas flow visible from all angles, an onboard menu of pre-installed gas conversions and electronic signal output to analogue and fieldbus interfaces.

Figure 1 The Mass-View^® from Bronkhorst

Aimed particularly at hospitals, research laboratories, industrial cleanrooms and the biotechnology and pharmaceutical sectors, where accuracy of the gas metering process is central to safe treatment, proper diagnosis, repeatability, accountability and quality, Bronkhorst’s Mass-View series consists of three gas flowmeters, with flow ranges of <2, 20 and 200 l_n/min, and three mass flow controllers of the same capacities, each with a built-in needle valve. Offering accuracy rates up to ±1.0 per cent FS plus ±1.0Rd, they feature pre-installed gases, including Air, N₂, O₂, CO₂, Ar and CH₄, eliminating the need to re-calibrate for different applications and thereby reducing the cost of ownership.

“VA meters, which measure volumetric flow, have been the uncomplicated choice for many years, particularly as people are familiar with the technology and their operation is simple to understand. But their relatively low accuracy and susceptibility to pressure and temperature variations means they are not really viable for many medical and life sciences applications, as they no longer represent ‘best available technology’,” says Bronkhorst UK’s Managing Director, Andrew Mangell.

“Price-wise, variable area meters are very competitive, of course, but we have costed our Mass-View flowmeters so they are comparable to a plastic or glass VA plus signal transmitter, or around the price of a metal tube rotameter,” he continues. “Besides, buying on installed price alone is not always valid, since improved accuracy and repeatability can translate into less wastage, more consistent processes, better research and diagnosis. The credibility of data is also enhanced for research purposes, legal requirements and accountability records.”

An acknowledged shortcoming of VA technology is that, during operation, flowmeter accuracy can quickly degrade once temperature and pressure deviate from standard calibration references, requiring regular recalibration and constant monitoring of T and P conditions, which in practice is rarely carried out consistently. In contrast, a thermal mass flowmeter, such as Mass-View, measures the actual mass of gas and does not require correction for changes in gas temperature, pressure or density, leading to greater accuracy, repeatability and compatibility of data; thus any applications that require precise monitoring and control of relatively low-flow gases would benefit from this measuring technique. Moreover, Mass-View’s rangeability, or turndown ratio between minimum and maximum flow rates, of up to 1:100 compares most favourably with a typical VA rating of just 1:10 or 1:12.

A potential safety hazard with many VA flowmeters occurs where a glass metering tube breaks, leading to the possibility of potentially dangerous gases leaking into the environment, and there is also the more routine problem of parallax error, when taking readings off the float from different viewpoints. The Mass-View design overcomes these drawbacks by removing fragile components from the flow path and employing an OLED screen, as used in mobile phones and MP3 players, to display an easily-interpreted bar graph and actual flow value. Giving a far brighter readout than LCDs, the display is clearly visible from all angles and in all light conditions, at the same time facilitating easy navigation through an onboard menu of pre-installed gases, flow ranges, alarm functions and other settings, using a four-way push button.

To enable straightforward replacement of existing VA meters, the Mass-View is also installed vertically and can be fitted with adapter sets for most common process connections. A plug-in power supply with universal 100-240 V input and 2 m cable is supplied, which conforms with current EN safety specifications, whilst there is also a choice of interconnection cables and free software tools for interfacing with Windows-based systems.

“VA meters fluctuate according to atmospheric conditions and most processes can’t cope with that level of variation. So we’ve taken what is good about VA instruments, notably their size, straightforward reading and affordability, then improved the accuracy, rangeability and safety, as well as adding the benefits of an output signal for data logging. We’ve also introduced multiple gas conversion capabilities to reduce inventory and recalibration costs,” concludes Andrew Mangell. “Mass-View’s modern aesthetics and digital technology bring flow measurement of this type into the 21st century.”

For more information visit www.bronkhorst.co.uk