Purge and pressurization is an alternative hazardous location protection concept that allows lesser rated equipment to be used in hazardous areas by segregating the equipment from the hazardous material.
The WORM goes where no other temperature sensor has gone before, literally! With its flexible design, it is able to fit in places that rigid sensors can't. It provides accurate readings while being extremely easy to maintain. Read this white paper to learn how the WORM provides a "one size fits all" solution to temperature sensors that saves you time and money.
Analyzing "Big Data" provides decision makers with tools to make better operational decisions impacting efficiency, costs, security, and ultimately contribute to greater profits. Download this white paper to learn the role of smart instrumentation, and find out how data is not only shaping business but changing the future of instrumentation
Without measurement there is no control. As with any type of measurement, results need to be expressed in a defined and clear way to allow everyone to interpret and apply those results correctly. Accurate measurements and good measurement practices are essential in industrial automation and process environments, as they have a direct effect on the success of the desired outcome.
Pressure, the measure of a force on a specified area, is a straightforward concept, however, depending on the application, there are many different ways of interpreting the force measurement. This white paper will identify the various units of pressure measurement, while discussing when and why certain pressure measurements are used in specific applications.
For decades, process instrumentation specifiers have faced the decision whether to use a mechanical switch or a continuous transmitter for a given application. Either type of instrument can be used to effectively control industrial processes and protect equipment and personnel -- and each has associated pros and cons. Application specifics typically drive decision-making, dictating which approach is most effective from performance, cost and lifecycle support perspectives.
The BLH Industrial Weighing Systems Handbook has been a primary reference since its first printing in 1967. This third edition presents vital information on weighing system performance, design and implementation tools.
Understanding the accuracy of a given flowmeter is an important field but it can also be misleading as different specifications are used to explain how accurate a flowmeter measurement actually measures. This paper discusses the different specifications and interprets the impact of them.
Why deal with accuracy?
The reasons for dealing with flowmeter accuracy specifications are many-folded. One important reason is from an economical point of view. The more accurate a flowmeter can measure, the more money you will save as the medium is measured with only very little inaccurately.
Another reason is in terms of dosing, where a given amount of a medium is added. This must be done with a high level of precision and the accuracy is thus important in order to dose correctly. This is critical in certain industries such as in pharma or chemical.
A third reason is in terms of billing purposes. By performing with good accuracy, you know exactly how much fluid flows into the process. Thereby, you are able to determine the right price of the product and thereby bill the customers correctly.
Therefore, knowing how much that flows through your system is paramount in order to make a profitable and solid business. You need to rely on a precise measurement with good accuracy. However, good accuracy must be obtained not only in one measurement, but in all measurements independent of the time.
Differential pressure (dP) sensors with electronic signal processing are increasing being used to monitor flow, filter condition and level. Since these devices offer linear and accurate output, they are also replacing the differential pressure switch that only support on-off condition and useless for closed loop control system. These dPs are often configured with expensive valves and fluid filled remote seals for added protection against corrosive media, radiation and/or extreme media temperature ranges when operating in demanding environments. In cold ambient environment specially operating in temperatures below -4 deg F (-20 deg C), the sensor need to be heated either by trace heater or within a heated enclosure to maintain the operation of the dP sensor. In addition to being expensive, these valves and seals tend to be bulky and require time to install and maintain. In many critical applications such as food and pharmaceuticals, filled fluids are a serious concern due to process contamination. In gaseous systems such as hydrogen and oxygen and semiconductor applications, fluid filled sensors are being banned since the leakage of fluid into the process could lead to an explosion and serious safety issues.
A new series of LVDT (linear variable differential transformer) based oil-less dP sensor with dual channel ASIC (applications specific integrated circuit) have been developed that can operate in a wide range of corrosive materials, radiation and temperature without any oil filling and bulky sealing systems. By encapsulating LVDT proven technology with digital compensation, the pressure sensors combine the benefits of friction-free operation, environmental robustness and unlimited mechanical life. By selecting the diaphragm thickness and material properties, Table 1 show the dP ranges that can be produced using the LVDT technology.
This gas analysis kit allows accurate measurement of highly reactive components such as NH3, HF, HCI or water, as well as O2, CO and CO2, directly in extremely dusty or corrosive samples, where an extractive sampling system would quickly fail or require constant maintenance.
ABB's Flow Measurement Handbook has helped generations of instrumentation practitioners navigate the application ins and outs of industrial flow measurement devices. Its latest edition entitled "Industrial Flow Measurement -- Basics and Practice," is available here in manageable chapters, downloadable as PDFs; this week we feature "Operating principles and application of flow instrumentation based on positive displacement, turbine, vortex and swirl phenomena."
Some control loops cannot be improved by tuning. In fact, you might even make matters worse by tuning them. This white paper discusses four types of PID control loops that you absolutely should NOT tune. Download the white paper to discover how you can save time and get better results by NOT tuning.
This paper will address the application of Guided Wave Radar (GWR), also known as Time Domain Reflectometry (TDR), in your steam loop. Included will be discussions of how this technology functions and differs from more traditional forms of level indication.
The heart and soul of any boiler based power generation system is the steam loop or circuit. Without the proper availability of water in this system, efficiency suffers. In more extreme circumstances damage to other components from either too much water (carryover) or too little water (low water condition) will occur and shorten a boiler's lifespan. In the most extreme situation a dry fire accident could occur resulting in severe damage and personal injury.
Level indication in the steam loop is critical, yet the methods employed to measure it have been slow to evolve or change. Some of that has been due to code requirements (PG-60 of the ASME Boiler and Pressure Vessel Code) or a simple lack of confidence in "new" technology. It has only been in the past 15 to 20 years (recent in terms of boiler/steam loop history) that technologies such as magnetic level gages or differential pressure devices have been used in place of direct reading glass gauges on applications such as feedwater tanks, high pressure preheaters or hotwells. These same devices are now utilized for drum level indication as well. The most recent addition to the technology basket for steam loop applications has been Guided Wave Radar. Used in conjunction with other technologies it is seen as a reliable cost effective choice for redundant level measurement in all steam loop applications, including drum level.
Optofluidics is a relatively new interdisciplinary technology that combines optics and fluidics. It extends to both the realization of optical effects and components and the analysis of fluids in motion. Fluids comprise liquids and gases, but also bulk solid materials that flow through pipelines and their fittings.
This technology furnishes diagnostic and analytical methods in which certain characteristics, constituents or parameters of fluids in motion such as density, volume, colour, or content of noxious substances are detected and evaluated. For this purpose, the fluid is charged with information that can be subsequently read by optical components. The fluid thus becomes a medium that carries in itself the code for optical analysis. Devices such as cameras and sensors visualize the diagnosis in real time, without the process flow having to be interrupted. In future, optofluidic analysis methods could replace time-consuming sampling and stabilize process flow, while reducing the number of components required and maintenance costs.
In many control loops, we use 2-wire transmitters to convert various process signals representing flow, speed, position, level, temperature, pressure, strain, pH, etc., to 4-20mA DC for the purpose of transmitting the signal over some distance with little or no loss of signal. This paper reviews the operation and advantages of the 4-20mA transmission standard and the use of loop-powered transmitters.
From push buttons to touch screens, operator panels have become smarter, easier to use, and much more capable than ever before. In this white paper, Advantech takes a detailed look at what makes an operator panel work best, what you should know about buying smart operator panels and what to do with one once you have it.
Equipment designers frequently must incorporate miniature solenoid valves into their pneumatic designs. These valves are important components of medical devices and instrumentation as well as environmental, analytical, and similar product applications. However, all too often, designers find themselves frustrated. They face compromise after compromise. Pressure for increasingly miniaturized devices complicates every step of the design and valve selection process. And missteps can wreak havoc. How do designers balance the needs for reliability, extended service life, and standards compliance against often-contradictory performance requirements such as light weight, high flow, and optimum power use?
This report consolidates the expert views of designers and manufacturers with wide experience applying miniature solenoid valves for myriad uses across multiple industries. It presents a true insider's guide to which requirements are critical for common applications. It also highlights new valve technologies that may lessen or eliminate those troubling compromises.