Category: Process Plants Instrumentation
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How Redundancy is Achieved in Process Plants
In similar way to electronic systems, redundancy is extensively employed technique for enhancing the reliability of many industrial plants and processes. Because many process plants units such as pumps, valves and compressors involve moving parts, they are prone to wear and therefore require periodic inspection and maintenance. Where the plant is required to operate continuously,…
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NAMUR NE 107 Standard for Modern Instrumentation Diagnostics
NAMUR NE 107 is a standard adhered to by manufacturers during the design and fabrication of instruments. NAMUR NE 107 provides status signals that communicate clear messages and remedies. These status signals or diagnostic codes are categorized into four standard icons and colors making it easier for users to comprehend them irrespective of the manufacturer…
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Steam Conditioning Valves – Features, Advantages & Applications
The Work of Steam Conditioning Valves & Why they are used in Industrial Processes Typically in an industrial set up, it may be necessary downstream of the main process application of superheated steam to reduce its pressure and temperatures to enhance the process efficiency, protect the equipment or perform other processes. This can be accomplished…
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Steam Traps – Basic Features, Types & Applications
A steam trap is a control valve whose basic function is to allow condensate to flow, while preventing the passage of steam until it has given up its heat by condensing back to water; in other words, a steam trap is a self-contained valve which automatically drains condensate and discharges air and non-condensable gases from…
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Testing, Pre-commissioning & Plant Commissioning Requirements
Introduction A new installation must be fully tested to ensure that the equipment is in full working order prior to its being started. This testing is typically divided into three phases: Pre-Installation Testing This is the testing of each instrument for correct calibration and operation prior to its being installed in the field. Such testing…
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What is the Function of a Steam Desuperheater?
Whereas superheated steam offers an excellent source of energy for mechanical power generation, in most cases, steam at greatly reduced temperatures, near saturation, proves a more desirable commodity especially for most heat-transfer applications. Precise temperature control is required to enhance heating efficiency; eliminate unintentional superheat in throttling processes; or to protect the downstream product or…
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Control Valve Selection Guide
Valves are manual or automatic fluid controlling elements in a piping system; in other words, valves isolate, switch, and control fluid flow in piping systems. They are constructed to withstand specific range of temperature, pressure, corrosion, and mechanical stress. Valves can be operated manually using levers or gear operators or remotely using electric, pneumatic, electro-pneumatic…
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Volume Booster: Function, Operation & Application
Function of a Volume Booster A volume booster is a device that amplifies or boosts the volume of air supplied to the actuator, that is, it takes an input signal and produces an output of a large volume flow of air to the actuator; to be precise, a volume booster is a pneumatic device made…
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Electro-Pneumatic Valve Positioners: Function & Features
Valve positioners are motion-control devices that are made in such a way to actively compare valve stem position against the control signal, adjusting the actuator diaphragm or piston till the correct stem position is achieved, that is, in a nutshell a valve positioner’s goal is to ensure the mechanical valve’s position matches the command signal…
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Instrument Grounding: General Guidelines
Specific attention must be paid to instrument grounding, especially where field instruments are connected to a computer or microprocessor based control system. Where cable screens are used, ground continuity of screens must be maintained throughout the installation with the grounding at one point only such as that in the control room. At the field end…