Condition monitoring for

Condition Monitoring for Intelligent Household Appliances J. Goschnick and R. Korber... 

An environment should have appropriate controls for temperature, pressure, and relative humidity. For aseptic production, cleanroom conditions monitored for particles and bioburden contamination are necessary. Equipment must be validated and maintained with current calibration. Processes must be developed and validated to ensure the production of pure and consistent product. 

H. Kamohara, A. Takinami, M. Takeda, M. Kano, S. Hasebe and I. Hashimoto, 2004, Produet Quality Estimation and Operating Condition Monitoring for Industrial Ethylene Fraetionator, J. Chem. Eng. Japan, Vol.. 37, No.3, 422... 

Sondermann-Woelke, C., Meyer, T, Dorociak, R., Gausemeyer, J., Sextro W. June (2012). Conceptual design of advanced condition monitoring for a self-optimizing system based on its principle solution. In 21th European Safety Reliability Conference, Helsinki (Finland), session 28, 10 pages. 

Maillart L.M. Pollock S.M. 2002. Cost-optimal condition-monitoring for predictive maintenance of 2-phase systems, IEEE Transactions on Reliability 51(3) 322-330. 

Figure 1. Scheme of condition monitoring for fault detection. 

A more sophisticated and increasingly popular method of on-condItion maintenance is to monitor the performance of equipment on-line. For example, a piece of rotating equipment such as a turbine may be monitored for vibration and mechanical performance (speed, inlet and outlet pressure, throughput). If a base-line performance is established, then deviations from this may indicate that the turbine has a mechanical problem which will reduce its performance or lead to failure. This would be used to alert the operators that some form of repair is required. 

The usual precautions must be observed around the high tension electrical equipment supplying power. The carbon monoxide formed, if collected in closed furnaces, is usually handled through blowers, scmbbers, and thence to a pipe transmission system. As calcium carbide exposed to water readily generates acetylene, the numerous cooling sections required must be constandy monitored for leaks. When acetylene is generated, proper precautions must be taken because of explosibiUty of air—acetylene mixtures over a wide range of concentrations (from 2.5 to 82% acetylene by volume) and the dammabiUty of 82—100% mixtures under certain conditions. 

Purpose Unfavourable operating conditions Fault conditions Protection Single-device motor protection relays Summary of total motor protection Motor protection by thermistors Monitoring of a motor s actual operating conditions Switchgears for motor protection Selection of main components Fuse-free system... 

Implementation of advanced performance degradation models, necessitate the inclusion of advanced instrumentation and sensors such as pyrometers for monitoring hot section components, dynamic pressure transducers for detection of surge and other flow instabilities such as combustion especially in the new dry low NO combustors. To fully round out a condition monitoring system the use of expert systems in determining fault and life cycle of various components is a necessity. 

The new purchasing mantra for the new utility plants is life cycle cost and to properly ensure that this is achieved a total performance condition monitoring strategy is unsurpassed. 

Figure 19-8. A block diagram for an on-line condition monitoring system.

A new maintenance system is introduced based on the new mantra for the selection of all equipment Life Cycle Cost. This new system especially for major power plants is based on the combination of total condition monitoring, and the maintenance principles of total productive maintenance, and is called the Performance Based Total Productive Maintenance System. ... 

Master plan development for PTPM. A master plan must be created. Total condition monitoring equipment should be designed, and equipment should be purchased. 

To determine if steady state conditions exist, the temperatures and pressures in the column can be tabulated to assure that they are reasonably unchanging. Laboratoiy analyses are usually too slow and expensive for checking lined out conditions. Monitoring reflux accumulator boiloff is often an effective way of noting concentration changes. Simply let a sample of the accumulator liquid boil at atmospheric pressure in a bottle with a thermometer inserted. This method is limited to light hydrocarbons and is not accurate enough for precision fractionation. 

Maintenance "indicators" are available to help facility staff determine when routine maintenance is required. For example, air filters are often neglected (sometimes due to reasons such as difficult access) and fail to receive maintenance at proper intervals. Installation of an inexpensive manometer, an instrument used to monitor the pressure loss across a filter bank, can give an immediate indication of filter condition without having to open the unit to visually observe the actual filter. Computerized systems are available that can prompt staff to carry out maintenance activities at the proper intervals. Some of these programs can be connected to building equipment so that a signal is transmitted to staff if a piece of equipment malfunctions. Individual areas can be monitored for temperature, air movement, humidity, and carbon dioxide, and new sensors are constantly entering the market. 

Most turbines have relatively long bearing spans and highly flexible shafts. These factors, coupled with variations in process flow conditions, make turbine rotors highly susceptible to shaft deflection during normal operation. Typically, turbines operate in either the second or third mode and should have narrowbands at the second (2x) and third (3x) harmonics of shaft speed to monitor for mode shape. 

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