Time filter

Source Type

Knoxville, TN, United States

Hashemian H.M.,Analysis and Measurement Services Corporation
Annals of Nuclear Energy | Year: 2011

In 2008-2009, the High Flux Isotope Reactor (HFIR) at the Oak Ridge National Laboratory (ORNL) tested the potential of predictive or condition-based maintenance techniques to reduce maintenance costs, minimize the risk of catastrophic failures, and maximize system availability by attaching wireless-based sensors to selected rotating equipment at HFIR. Rotating equipment is an ideal "test case" for the viability of integrated, online predictive maintenance strategies because motors, bearings, and shafts are ubiquitous in nuclear power plants and because the maintenance methods typically performed on rotating equipment today (such as portable or handheld vibration data collection equipment) are highly labor-intensive. The HFIR project achieved all five of its objectives: (1) to identify rotating machinery of the types used in research reactors and determine their operational characteristics, degradation mechanisms, and failure modes, (2) to establish a predictive maintenance program for rotating equipment in research reactors, (3) to identify wireless sensors that are suitable for predictive maintenance of rotating machinery and test them in a laboratory setting, (4) to establish the requirements and procedures to be followed when implementing wireless sensors for predictive maintenance in research reactors, and (5) to develop a conceptual design for a predictive maintenance system for research reactors based on wireless sensors. The project demonstrated that wireless sensors offer an effective method for monitoring key process conditions continuously and remotely, thereby enhancing the safety, reliability, and efficiency of the aging research reactor fleet. © 2010 Elsevier Ltd. All rights reserved.

Hashemian H.M.,Analysis and Measurement Services Corporation
Nuclear Engineering and Design | Year: 2010

Pressure to improve plant efficiency and maximize safety and the increasing age of existing NPPs are forcing the global nuclear power industry to confront the challenges of aging - caused by stressors such as temperature, humidity, radiation, electricity, and vibration - in key instrument & control (I&C) components like pressure transmitters, temperature sensors, neutron detectors, and cables. Traditional aging management methods, such as equipment replacement, required the process to be shut down. Recent aging management technologies, collectively known as online monitoring (OLM), enable plants to monitor the condition and aging of their installed I&C while the plant is operating. Developed through R&D initiatives worldwide, such OLM techniques include low- and high-frequency methods that use existing sensors, such as noise analysis; methods based on test or diagnostic sensors, such as for vibration-measuring accelerometers; and methods, such as the power interrupt (PI) test, based on active measurements made by injecting a test signal into the component under test. A review of these aging management methods, their effectiveness, and their interrelation provides a foundation for understanding the next stage in the evolution of OLM: truly integrated hybrid OLM systems capable of robust condition monitoring in both novel and familiar operating conditions. © 2010 Elsevier B.V. All rights reserved.

Analysis and Measurement Services Corporation | Date: 2013-05-21

A pitot tube diagnostic system including a data acquisition unit to acquire an output signal of a pitot-static system, the output signal having a static component and a dynamic component, and a processing unit to monitor the dynamic component for one or more characteristics that deviate from one or more predetermined reference characteristics to indicate impairment of the pitot-static system.

Analysis and Measurement Services Corporation | Date: 2014-08-07

A temperature detector and method of measuring temperature to obtain temperature readings in environments, such as fluids and gasses, by measuring electrical characteristics of the temperature detector that are influenced by the temperature. The temperature detector can be arranged such that a plurality of measurements can be obtained to provide sufficient diversity and redundancy of the measurements for enhanced diagnostics to be performed, such as optimization for fast dynamic response, calibration stability, in-situ response time testability, and in-situ calibration testability.

Analysis and Measurement Services Corporation | Date: 2013-06-18

Systems and methods of monitoring a rod control system of a nuclear power plant, including calculating impedance of at least one coil of a rod movement mechanism non-intrusively while the system is operating, comparing a measured impedance to a reference impedance, and determining if the measured impedance deviates from the reference impedance value by a predetermined amount to indicate degradation of the rod control system.

Discover hidden collaborations