Middle East Turbomachinery Symposium (METS)
Permanent URI for this collection
2015
Middle Eastern Tubomachinery Symposium (3rd)
Case Studies | Lectures | Tutorials | Short Courses | Discussion Groups
2013
Middle Eastern Tubomachinery Symposium (2nd)
Case Studies | Lectures | Tutorials | Short Courses | Discussion Groups
2011
Middle Eastern Tubomachinery Symposium (1st)
Case Studies | Lectures | Tutorials
Browse
Recent Submissions
Item VSD Motor Intermittent Vibrations Excursions(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Van De Flier, Gertjan; Anwar Syed, AsadItem Resolving Cavitation Problems of High Energy Water Injection Pumps(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Al-Shuhail, Yousuf; Al-Ali, Saad; Al-Qahtani, Abdulaziz; van den Berg, Nico; Bastiaansen, Tim•Introduction - Project objectives - History - Field data •Analysis method - Computational Fluid Dynamics (CFD) - Visualization test •Project results •Lessons learnedItem Advancement in Vibration Monitoring Techniques to Identify and Prevent Motor Failures on MOL Pumps at QP Offshore(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Sudardjat, Isham; Ganesh, SankarContents: Background Machine description Data analysis: • First Visit • Second Visit Initial Conclusions Machine Inspection results Final Conclusions Actions Taken Lessons LearnedItem DEVELOPMENT AND DESIGN OF ANTISURGE AND PERFORMANCE CONTROL SYSTEMS FOR CENTRIFUGAL COMPRESSORS(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Mirsky, Saul; Jacobson, Wayne; Tiscornia, David; McWhirter, Jeff; Zaghloul, MedhatThe development and design of control systems for centrifugal and axial compressors is discussed and explanations given to bring together features of control systems on varying machine designs. Potential problems resulting from such differences will be addressed and resolutions offered.Item Head-flange O-rings on Barrel Type Centrifugal Compressor Units at RasGas: Issues & Resolutions(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Shatri, Quraisy; Rajani, Rajeshkumar; Wakileh, Basel; Baldassarre, Leonardo; Cianti, Andrea; Armenzani, AlbertoRasGas is operating many centrifugal compressors from different major OEM’s. Of an OEM product-line, twenty-four (24) centrifugal compressors with a total rated power of roughly ~ 900 Mega-watt are in operation, out of which 16 are barrel type (BCL). Driven by an end-cover or Head-Flange (HF) O-ring failure during early months of operation, indicated via gas leak in to atmosphere, a series of actions were taken due to serious uncertainties of the HF O-rings reliability, for both the units already in operations and the ones under Pre-Mechanical Completion. Actions included materials properties, tests data, selection (e.g. spliced versus single piece) and manufacturing processes and O-ring makers and supplier’s traceability. A comprehensive Risk Assessment led by Project Team and supported by EM experts was carried-out to determine whether HF O-rings already installed in similar unit shall be replaced right away prior to putting it in to full operation. Test schedule to accept or reject assembled HF at site was defined. Small modifications for continues monitoring of the HF O-rings during operation was also established. This Case Study is intended to share some lessons of technical aspects reviewed including selection processes. Site challenges to replace the HF O-rings for such barrel type centrifugal compressors and the site test schedule are also covered.Item ADVANCEMENTS IN MECHANICAL SEALING - API 682 FOURTH EDITION(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Huebner, Michael; Buck, Gordon; Azibert, HenriAPI 682 is the leading document for mechanical seals in petrochemical, chemical, and pipeline services worldwide. It has combined the aspects of seal design, testing, standardization, and applications to provide the users and OEMs alike with a common source of information for mechanical seals. As seal technology has advanced, the standard has expanded to incorporate new seal designs, materials, seal selection guidance, and piping plans. The current edition, the Fourth Edition, was published in May of 2014 and is now available for purchase. This tutorial will cover the major changes introduced in the Fourth Edition.Item TUTORIAL: TRANSIENT MODELING AND ANALYSIS OF CENTRIFUGAL COMPRESSORS(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Garcia-Hernandez, Augusto; Bennett, JeffreyCentrifugal compressors are subject to transient events, such as emergency shutdowns, which can cause energetic surge events during rapid shutdown transients. Many modeling tools are used to predict the behavior of compressor systems during fast transient events. Even more, centrifugal compressor dynamic modeling is a valuable assessment tool that can help improve the design of the compressor anti-surge system to prevent harsh conditions while the unit is coasting down. Modeling of centrifugal compressor transient events requires a detailed evaluation of many system variables to obtain accurate results. Additionally, many parameters should be included and analyzed to adjust the model and obtain acceptable predictions. Those parameters can include recycle valve characteristics, the controller and actuator, suction and discharge piping volumes, aftercoolers, and operating conditions. Other parameters, such as machine coast down speed and inertia and different control response times will determine if the compressor will reach its surge limit at a detrimental high head condition, avoid it or go through it at low acceptable energy conditions. Many designs use general guidelines to select and plan the compressor anti-surge system and its main components. For example, the recycle valve type, size and actuation time are key parameters during the shutdown of the compressor unit since they directly affect the amount of flow through the compressor and its reaction time. Other factors are also relevant and should be assessed in detail to assure a proper design to avoid such transient events as a sudden shutdown of a compressor from a full load or high head operating conditions resulting in damaging surge events. In order to refine the simulation approach of the transients in centrifugal compressors, an extensive assessment has been conducted of the main parameters that will affect the modeling predictions. Parameters such as recycle valve size, type, actuation time, after-cooler volume, friction factors, unit speed coast down predictions, compressor map, isolation valve control, acting time, as well as placement of the discharge check valve influence the modeling predictions considerably. Therefore, parametric studies of some of those variables have helped to refine and adjust the modeling technique while improving the accuracy of the results. Moreover, computational predictions have been compared against high fidelity – high accuracy data collected in a full scale compressor system. Initial comparisons indicated reasonable results while adjustments in the technique and main assumptions improved the modeling predictions considerably. A generic methodology to improve modeling predictions and main considerations are part of the analysis. In addition, a comparison of the modeling results and experimental data are presented and complemented with parametric studies of different variables. In general, this work should provide guidelines for advancing the modeling of centrifugal compressor transients as well as showing the application of a valuable tool for designing surge control systems for centrifugal compressors.Item Large Gearbox Vibration Monitoring Techniques(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Ramsekar, Dakshina Murthy; Muchaweck, FranzItem BABBITTED BEARING HEALTH ASSESSMENT(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Whalen, John; Hess, Thomas; Allen, Jim; Craighton, JackWithin most plants there is often a desire to extend the time between outages. Several factors determine this but one to consider is the bearings ability to run for the extended time. This Tutorial will address common bearing failure mechanisms, tools available to diagnose these problems and ways to use that information to make decisions on continued operation. Evaluation consists of analysis of Condition Monitoring information coupled with rotor dynamic analysis and computerized bearing modeling. A case study will be presented that details the evaluation of a distressed bearing. Analysis allowed the user to determine they could slightly reduce running speed (to limit vibration to a certain level) and continue to run to the scheduled outage date. There will then be a discussion on bearing robustness and ways to design bearings for long life. A case study will be presented where an Ethylene plant desired to extend the time between outages but the existing bearings prohibited that. The determination was made that upgrading the bearings to a more robust design would allow the extended time between outages.Item TUTORIAL: GAS TURBINE PERFORMANCE(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Kurz, Rainer; Brun, KlausThe power and efficiency characteristics of a gas turbine are the result of a complex interaction of different turbo machines and a combustion system. In this tutorial, we will address the basic characteristics of each of the components in a gas turbine (compressor, gas generator turbine, power turbine) and the impact of typical control limits and control concepts. The goal is to provide explanations for the operational characteristics of typical industrial gas turbines, emphasizing the interaction between the gas turbine components. The concept of component matching is explained. Additionally, methods are introduced that allow the use of data for trending and comparison purposes. The impact of component degradation on individual component performance, as well as overall engine performance is discussed, together with strategies to reduce the impact of degradation In particular, the following topics will be discussed: · The gas turbine as a system · Thermodynamics and aerodynamics · Component matching · Off-design behavior of gas turbines · Low fuel gas pressure · Accessory loads · Single-shaft versus two-shaft engines · Variable inlet and stator vanes · Control temperature · Transient behavior · Thermo dynamical parameters of exhaust gases The topics presented should enhance the understanding of the principles that are reflected in performance maps for gas turbines, or, in other words, explain the operation principles of a gas turbine in industrial applications.Item TUTORIAL: SURGE CONTROL AND DYNAMIC BEHAVIOR FOR CENTRIFUGAL GAS COMPRESSORS(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Kurz, Rainer; White, Robert; Brun, Klaus; Winklemann, BernhardThis tutorial discusses the design and function of surge control systems, or more precisely, surge avoidance systems on the basis of the behavior of centrifugal compressors when they interact with compression systems. Therefore, the control system, as well as the phenomenon of surge and stall is discussed. The paper emphasizes the interrelation between the process system and the compressor. Regarding the compressor, different methods of controlling the compressor are discussed, together with different operating regions like stall and choke. The differences between stall and surge are explained. Additionally, the impact of the process and how the process dynamics interact with the compressor is analyzed, categorized, and explained. Based on the above, process control and in particular, surge control systems are discussed. Critical features of surge control systems are explained, and options for different arrangements are given.Item END USER’S APPROACH TO CALCULATING COMPRESSOR PERFORMANCE(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Khader, Ameer; Deshpande, Atul; White, Nicholas; Abdelghafour, MohamedOil and Gas industry end users have generally approached the topic of centrifugal compressor performance estimation with little consideration to the effect of process gas conditions. This is customary since end users depend mostly on OEM methodologies. This tutorial argues that performance curves are dependent on process gas conditions. The tutorial touches on key gas properties and how they are used in compressor performance calculations. An explanation of the effect of process gas conditions is discussed, and how to develop and make use of invariant performance curves and therefore, estimation results are improved. Finally, dimensionless analysis laws are applied using an end user developed performance calculation tool. The tool has been successfully implemented in plant conditions with proven results.Item Shop Rotordynamic Testing -- Options, Objectives, Benefits and Practices(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Kocur, John; Cloud, C. HunterItem Premature Dry Gas Seal Failure on a Sales Gas Centrifugal Compressor(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Vidal, SergioIndex •Introduction •Mechanical findings •DCS findings •VMS findings •Analysis •Conclusions •Recomendations •References •CommentsItem STABILITY CONSIDERATIONS – A SIMPLIFIED APPROACH(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Baumann, UrsIn many cases it is necessary to judge the stability behavior of a specific compressor. This might be the OEM checking the feasibility of a proposed compressor layout or it might be the user judging one of his machines which causes troubles in operation. API 617 suggests a stability level I or level II analysis. The shortcoming of the level I analysis is that it considers only the global cross-coupling stiffness of the entire stages neglecting the actual seal design of a compressor. Thus the damping of a machine is always decreasing with increasing load which is not reflecting the true stability behavior of modern turbo compressors. On the other hand a level II analysis requires detailed insight into the machine design which might not be defined at that time or which is not known to the user. To overcome these problems this tutorial proposes a different kind of stability check which only requires a minimum of operational and design data and delivers a comprehensible and (relatively) reliable picture of the stability behavior of the investigated compressor. This tutorial derives the used stability criterion and explains the effect of the circumferential speed of the gas in the seal gap on the rotordynamic behavior. Finally it presents example calculations for different seal configurations and compares the resulting stability judgments to the results of the classical API level II analysis and to the results of experimentally determined rotor damping.Item MATERIALS SELECTION AND DEVELOPMENT FOR CENTRIFUGAL COMPRESSORS OPERATING IN EXTREME SOUR & ACID GAS SERVICE(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Cappuccini, Filippo; Giannozzi, Massimo; Romanelli, Marco; Pietrangeli, Emanuele; Di Pietro, Domenico; Buccioni, MassimilanoThe rising demand for oil and gas has led us to exploit oil fields and gas reservoirs with increasing amounts of contaminants. Reserves of natural gas are abundant, but about 40% of the fields contain high concentrations of hydrogen sulfide, carbon dioxide, and chlorides. The harshening environment represents a challenge for the suitability of common classes of materials used for design and manufacturing of centrifugal compressor components. According to NACE MR0175/ISO15156, a fit-for-purpose approach has been extensively used to prove the steel’s resistance in simulated field conditions and characterize the environmental limits of most martensitic and precipitation hardening stainless steels in terms of partial pressure of carbon dioxide, hydrogen sulfide, and chlorides. The literature available on the subject generally agrees that the contaminants’ concentration levels exceed the possibility of risk presented by stainless steels to turbo-machine reliability, and in worst cases to operators’ safety. Nickel-based alloys are the most robust solution to overcome the above limitations, guaranteeing high mechanical strength and resistance against stress corrosion cracking mechanisms in expected compressors’ environments. This paper describes the advance in nickel-based alloys’ application and production of centrifugal compressors (CC) for extreme sour and acid conditions, with work that reveals the development of alternative manufacturing routes for rotor and stator components in turbomachinery. A detailed explanation of nickel-based alloys’ metallurgy, application and manufacturing capability is also given, along with recent developments of new alloys to bridge the gap between iron-base and nickel-base alloys, providing cost effective materials with enhanced corrosion resistance.Item Reciprocating Compressors 101(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Machu, Gunther; Andre Eijk, Ing.Item Combustion, Fuels and Emissions for Industrial Gas Turbines(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Welch, Michael; Igoe, BrianIt is important that gas turbines used in Oil & Gas applications can burn a wide variety of fuels with the minimum impact on the environment or economics. Many types of gaseous and liquid fuels that can be used in Gas Turbines are discussed, as will be the two basic types of combustion system employed – ‘conventional’ and ‘Dry Low Emissions’ – along with the flexibility of these systems to accept different types of fuel. Some of the common contaminants found in fuels are discussed along with the impact these have on the operability and maintenance of industrial and aero-derivative gas turbines.Item Root Cause Failure Analysis for Machinery and Piping Part 1: Introduction to RCFA(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Allison, Tim; Chirathadam, Thomas; Ransom, David; Delgado, HectorItem Introduction to Industrial Gas Turbines(Turbomachinery Laboratory, Texas A&M Engineering Experiment Station, 2015) Kurz, Rainer; Winklemann, Bernhard