CCJ Archives: 3Q 2007

Detailed presentations on DLN-1troubleshooting, ZLD solutions, varnish prevention identify outage actions to improve plant performance

The 2007 meeting of the 7EA Users Group, October 9-11, in San Francisco, was the largest in recent memory with 110 owner/operators attending and 78 products/services suppliers participating in the vendor fair on Wednesday evening. The technical program developed by the steering committee (Sidebar 1) was top-notch. more

Replacing jaw clutches with automatic ones can improve operating flexibility, reduce maintenance

By Morgan Hendry, SSS Clutch Company Inc

Gas-turbine (GT) manufacturers work continuously to improve their product lines. Likewise, users take steps at the plant level to reduce their O&M costs, extend maintenance intervals, and enhance the operation of their machines— often growing revenue in the process. Many equipment upgrades/ retrofits can be made at relatively low cost and can be accomplished during a short, planned outage. more

GE Roundtable highlights fall meeting with meaningful discussion of issues/solutions for Frames 7B-FA

South Shore Harbour Resort & Conference Center, League Ci ty, Tex, whi ch ho s t e d CTOTF’s 32nd annual Fall Turbine Forum and trade show, September 16-20, is a superior meeting location: easy access to the airport, close to many gas-turbine-based powerplants, a stone’s throw from Houston’s many repair shops, firstclass accommodations, and good food. more

How to conduct an objective investigation of a gas-turbine event

Gas turbines (GTs) truly are engineering marvels. Their sophisticated design, materials, and operation challenge the limits of modern technology. When one of these machines ‘breaks,’ understanding what happened, and why, is a demanding exercise requiring the participation of experts in equipment forensics

By Ron Munson and John Malloy, Mechanical & Materials Engineering LLC (M&M Engineering) more

User networks provide valuable guidance for outage planning

The first 10 to 15 years or so of a gas-turbine (GT) user group’s existence usually are focused on resolving outstanding issues with the “new” engine model. When a proactive group of knowledgeable owner/operators sits across the table from the OEM’s engineers, divideand- conquer and other avoidance tactics become ineffective; finding solutions becomes everyone’s goal. Issues are identified and prioritized, and programs to resolve them are planned and implemented. Periodic web-based conferences and faceto- face meetings are conducted to keep customers apprised of progress and one-by-one the deficiencies are corrected. more

How to get more power from your generator

By William G Moore, PE, National Electric Coil

Gas-turbine (GT) manufacturers offer what appears t o be a never – ending stream of product improvements for their installed fleets, many aimed at boosting performance and/or reducing emissions. Such improvements generally are accompanied by an increase in power output; the promise of higher revenue often justifies buying the upgrade. more

Incorporate lessons learned into specifications for new units

By Brent Cosgrove, PE, HRST Inc

Next to the gas turbine (GT), the heat-recovery steam generator (HRSG) has the greatest impact on combinedcycle system performance. Failure to address industry lessons learned in the specification for a new unit can put your plant at a competitive disadvantage. In the unforgiving world of merchant power generation, this can mean a balance sheet with red ink. For example, if your new boiler is susceptible to fouling and you have not provided a means for dealing with it, heat rate will increase—and so will gas consumption. Because fuel accounts for more than 80% of the life-cycle cost of a typical combined cycle, even a relatively slight increase in fuel use can have a significant impact on the price of power. more

Key elements of successful PM programs for turbine bypass systems

By Steve Freitas and Jason Moore, CCI—Control Components Inc

Steam-turbine bypass systems are used in combinedcycle plants during startup, shutdown, and load rejection. The most common arrangement is configured with a high-pressureturbine bypass to cold reheat and an intermediate-/low-pressure-turbine bypass to the condenser. The service life of a bypass system can be shortened dramatically by installation and control problems that cause severe thermal stresses conducive to metal fatigue. Cracking attributed to thermal fatigue has occurred in valve trims, bodies, desuperheaters, and downstream piping, and is most acute in plants cycling daily. more