Gas Turbine Condition Monitoring Research Articles

TIGER: knowledge based gas turbine condition monitoring

Given the critical nature of gas turbines in most industrial plants, their availability is of prime importance. Asso ciated maintenance costs can also be extremely high and hence, it is a high priority to find ways of reducing maintenance costs and increasing the availability of the gas turbine. Routine preventative maintenance techniques have been used for many years t o minimise major problems by routinely checking and taking care of small problems. This has produced some good results, but it is desirable to do even better. As a result, as a major move towards condition based maintenance and condition monitoring of gas turbines, the goal is to monitor the turbine on a regular basis in order to establish when maintenance actions need to be performed based on the condition of the turbine rather than a fixed number of operating hours. The core task of condition monitoring includes two elements: the first is regular and consistent data collection; and the second is the interpretation or analysis of that data. Two of the major approaches to condition monitoring are performance monitoring and vibration based condition mon itoring. The TIGER gas turbine condition monitoring system [1] addresses the performance monitoring aspects. It has the capability to be integrated with vibration based condition monitoring, but its primary focus is continuous real -time performance ass essment. TIGER can be considered the most advanced software tool for condition monitoring of the performance of gas turbines available today. It runs continuously on-line to the turbine, sampling the key operating parameters at once per second intervals, it performs a wide variety of checks including limit checking, dynamic response and consistency with model based predictions. It also provides extensive graphical user interface displays to help view the state of the turbine. TIGER includes an extensive trending support system to allow the user to select sets of data and view long -term trends. The TIGER condition monitoring system has been in continuous use at the Exxon Chemical Fife Ethylene Plant for over two years. It has been instrumental in identi fying the underlying problems for a number of situations, one of which resulted in considerable cost benefit to Exxon [2]. This paper gives an overview of the TIGER functionality and its use at Exxon Chemical.

Tiger: real-time situation assessment of dynamic systems

Industry is dominated by dynamic systems such as process control of chemical plants or steel plants and power generation, ranging to areas such as ecological systems and traffic systems. A challenging problem is to perform real-time monitoring and diagnosis of such dynamic systems. The paper describes the work of the TIGER ESPRIT Project in performing real-time situation assessment of dynamic systems. The goal of TIGER is to monitor a complex dynamic system in real time and make an assessment of whether it is working properly. If it is not working properly, it is desirable to identify the cause of the problem either from a set of known faults or to characterise an unknown fault. This work is applied in the application domain of condition monitoring of gas turbines. The project is developing and demonstrating its techniques on two industrial gas turbines; a 28 mW gas turbine used as the prime power for a chemical plant and a small auxiliary power gas turbine used in aviation. The Project is investigating a variety of tools and techniques for real-time situation assessment. These include a high-speed rule-based compiler, a situation assessment tool able to monitor dynamic responses over time, qualitative and numerical prediction of turbine response, and model-based diagnosis to help identify unknown faults. A prototype system is currently in use at a chemical plant performing monitoring and diagnosis in real-time.

Marine Gas Turbine Evaluation and Research at the Admiralty Test House, RAE Pyestock

The Admiralty Test House (ATH) at the Royal Aerospace Establishment Pyestock has provided test bed facilities for evaluation of marine gas turbines and ancillary equipments for Royal Naval use since 1952. While the ATH is presently undergoing an extensive refurbishment program in preparation for trials of the Rolls-Royce 20MW Spey SM1C, research continues on a number of innovative gas turbine condition monitoring techniques. This paper presents a brief history of the Marine Gas Turbine Section and describes the facilities of the ATH following major refurbishment. The capabilities of the steady-state and transient data gathering facilities are outlined, together with the automated engine and test control systems, which provide cost-effective engine evaluation in both endurance and minor equipment trials.

The application of ferrography to the condition monitoring of gas turbines

The use of ferrography to allow gas turbines to be operated with safety and economy is outlined. Direct reading ferrographic trend analysis appears to be potentially attractive. Automation of the process has been established. Gas stream analysis may be rewarding. Analytical ferrography provides essential information on specific vital components to supplement information from other techniques to allow more accurate decisions concerning machinery condition and maintenance action. User experience is reviewed.

Condition monitoring of gas turbines — An exploratory investigation of Ferrographic trend analysis

To aid the application of Ferrogaphic analysis to machine condition monitoring, a programme of trend analysis of gas turbine engines of the same type in the fleet of a single operator was carried out using the direct reading Ferrograph. The most informative method was found to be cumulative plots of the total wear and severity of wear on the same graph. Convergence of the curves gives an early warning of uncharacteristic trends which should be investigated by full Ferrographic analysis; a cross-over of the curves indicates that urgent action is required.