The new year is upon us, and the time for reminiscing has passed. As such, flow control users must now look forward to prepare for new things to come in the 2005 campaign.
Engineers are constantly under pressure to achieve faster time to market, minimize costs, and generally do more with less. Technology should help facilitate such efforts, but unfortunately changes in technology often bring about integration issues and other unforeseen circumstances. Therefore, understanding the latest trends and how they impact existing processes is crucial to success.
Currently, there are several key technology trends afoot that impact the design, operation, and implementation of flow control components in broader control systems. Even though some of these trends are not entirely new, it’s still important to keep them in mind and be aware of their impact. The following provides a look at some of the trends that figure to have significant influence on the way design engineers, plant engineers, and engineering managers do their jobs in 2005.
Trend 1: Going Mini
Global competition is forcing plants to shrink costs by building smaller, more efficient facilities. As a result, plant equipment needs to have a smaller footprint. Power and communications equipment has steadily gotten smaller and more compact. Consequently, control components are following a similar path.
Flow control components have been able to shrink in size thanks in large part to advances in silicon technology. Specifically, the physical size of electronic components and processors has enabled control component manufacturers to shrink package size and combine functions that formerly were spread out among several separate devices. This reduces component count, increases reliability, and saves space.
One example of the impact miniaturization has had on flow control is highlighted by a flow switch that was recently implemented aboard an aircraft carrier to sense jet-fuel flow. The system uses laser contaminant sensors to analyze the purity of the carrier’s jet fuel. A laser sends out a beam that passes through the fuel, and the reflections are then analyzed to determine the amount of contamination in the fuel and thus assess fuel purity.
One problem engineers were running into in this application was that the lasers stayed on all the time and would burn out, making for a costly repair. Since the laser sensors could only analyze jet-fuel contamination levels with the fuel flowing, the engineers decided to insert a flow sensor in the pipeline to sense when fuel wasn’t flowing, allowing the lasers to be turned off to prolong life. Prior to the advent of miniaturized flow sensors, this solution would not have been possible, as the sensor would have been too large to insert into the fuel line.
Trend 2: Intelligence at Device Level
The continual scaling of silicon has resulted in ever-shrinking and more powerful electronic circuits. Smaller electronic processors are increasingly more powerful and can fit in places where they couldn’t before, such as inside flow control components.
In closed-loop control systems, users require decision making at the point of application, not at a distant PC or logic controller. So components are being designed to not only sense conditions, but also control them.
Some flow control monitors now come with added intelligence to control the processes they’re monitoring. For instance, a recent application included a flow monitor in a pneumatic system that could detect leaks or shut off pumps when they weren’t needed.
Since electricity rates are based on peak usage, an intelligent monitor can save energy costs. Such flow control monitors can also be programmed to have compressors share loads and rotate demand, which also can cut energy costs. Intelligent devices can also store data, including usage, current, and time. The data can then be used at a later time to generate analysis reports.
In a process gas-flow monitoring application, a flow control device inserted into a pipe can provide an analog signal proportional to mass flow rate. Such devices are programmable and can also store high and low flow rates and temperatures, which can be recalled at any time for further analysis.
Trend 3: The Need for Speed
The ongoing push for increased productivity requires machines that run faster and more efficiently. But faster machines also require more responsive controls, as improving response times by even a few milliseconds can dramatically increase throughput.
At the component level, the trend toward speedier machines translates into faster microprocessors. With faster microprocessors, control components can respond to events more efficiently. Also, since many microprocessors now have signal processing capabilities, users can add intelligence at the component level and let control components make decisions that were once solely the function of logic controllers and PCs.
Trend 4: Remote Control
As recently as a decade ago, plant workers would collect data by walking up to a meter, reading a value, and recording it on a sheet of paper. Not any more. Distributed control systems have changed all of that. And with processing plants spread out around the globe from the Arctic Circle to Iraq, some of which have poorly trained or no on-site personnel, the need to remotely monitor and control events and processes in these plants is crucial.
No longer is it adequate to just sense conditions and sound an alarm. Nor is it enough to do a manual reset. Systems now require the capability to be remotely controlled and programmable. Increasingly, networks of wireless sensors and controllers are being put in place to do that job. These systems typically communicate over satellite transceivers or the Internet
Trend 5: Increasing Communications
The increased demand for remote control and monitoring requires reliable communication networks. Flow control components need to communicate with other control or monitoring systems to indicate and report on status and to take control actions when necessary. This communication can take place over a variety of network interfaces, including Ethernet, FOUNDATION Fieldbus, HART Protocol, PROFIBUS, or a number of other systems, including an ever-increasing array of wireless networks.
Communications are essential for plants located in remote sites such as refineries and pump stations. Some facilities have no personnel on site. In such a scenario, a remote operator can communicate wirelessly or via an Internet connection to turn pumps or valves on and off and check the status of plant operations.
Trend 6: Sensors Everywhere
Another key trend is the increasing use of sensors throughout processing plants. Sensors let plant operators know more and more about the processes they’re running and controlling. Plus, more data from sensors allows for tighter control over batch quality, as well as more efficient use of raw materials and energy, which ultimately increases production speed and just-in-time maintenance.
However, the ability to compile, analyze, and respond to the data received from this myriad of sensors can be quite a challenge. For increasingly intelligent flow control components, this means users must have the ability to do several things, such as store data, communicate effectively and reliably with interconnected control systems, and take control actions when necessary.
Taken together, the six trends outlined in this article are influencing how flow components are being designed and implemented in control systems across a broad range of industries. Knowing what’s happening in each of these areas can help users be more responsive to customer needs as the latest trends continue to impact the way plants and manufacturers do business.
About the Author
Kenneth Cybart is a senior applications engineer at E-T-A Circuit Breakers and Control. During his 15-year professional career, Mr. Cybart has worked as a design engineer, sales engineer, and applications engineer for manufacturers of electrical and electronic components and systems. He is a member of various technical committees including the UL standards work group, SAE, and the ABYC (American Boat and Yacht Council). Mr. Cybart can be reached at [email protected] or 847 827-7600.
For More Information: www.e-t-a.com
Courtesy of Flow Research
