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Consider eddy-current inspection of refurbished S3Bs prior to next use

Gas turbine owner/operators that do not send key personnel to user-group meetings may be taking unnecessary financial and safety risks. There is, perhaps, nowhere better to learn about issues you should be aware of. Consider the recent liberation events associated with third-stage buckets (S3B) in 7FA gas turbines. This was an agenda item of great […]

Drones facilitate some HRSG inspections, maintenance decision-making

Commercially available drones have become much more than a weekend novelty. Some facility owner/operators use them to survey and inspect transmission and distribution systems, pipelines, plant boundaries, or the plant itself. And some have now moved indoors to inspect wall panels, burner systems, and critical heat-transfer surfaces of large fossil-fueled boilers.

TCT, MTU, IHI share depot findings with LM6000 users

At annual meetings of the Western Turbine Users Inc (WTUI), the technical sessions begin on Monday afternoon. Over the next two days, users participate in the breakout session focusing on their engine of interest—LM2500, LM5000, LM6000, or LMS100. In sum, about nine hours of presentations and discussions in each track dig into the nitty gritty of gas turbine O&M. No better place for owner/operators of LM aeros to learn; if you don’t understand something, there’s always a colleague or supplier willing to help.

WTUI user presentations highly valued

Users will believe their colleagues in the trenches before they’ll believe what a vendor says. Four highly regarded user presentations made during the LM6000 breakout sessions, chaired by Andrew Gundershaug, plant manager, Calpine Solanno Peakers, are summarized in this issue of CCJ ONsite:

Special technical presentations profiled here focus on LM6000 maintenance, repair

This year the WTUI President Chuck Casey and the organization’s officers and directors (sidebar) increased by 50% the number of speakers participating in the group’s popular special technical presentations session to expose attendees to more subjects of interest beyond the basic engine. The Tuesday afternoon program in Palm Springs began at 2:30, an hour earlier than had been the norm. This provided time for three one-hour sessions in series, each offering three concurrent presentations.

First-stage nozzle repair for 7F engines combines brazing, welding

Gas-turbine repair techniques continue to evolve and proliferate against the backdrop of ever-present cost pressure, machines ageing in service, and competition among repair service firms. Ultimately, the choice will depend on many technical factors, but especially the owner/operator’s approach and budget for managing risk and the life stage the unit/components are at.

Mining data to identify problems, improve performance takes perseverance, know-how

The editors corralled Bob Anderson, principal, Competitive Power Resources, Palmetto, Fla, shortly after he concluded a planning meeting for the first “HRSG Forum with Bob Anderson,” Feb 28-Mar 1 and 2, 2017 to ask how he approaches problem diagnosis using data from the plant historian.

Anderson, a former plant manager and HRSG troubleshooter for a large utility’s F-class fleet, said the value of captured data for performance and problem assessments can’t be overstated. He shows by example, below, that one data plot can tell several stories and suggest multiple corrective actions.

Windscreens improve performance, reduce O&M cost of air-cooled condensers

Air-cooled condensers depend on steady air flow created by a properly designed system of axial-flow fans, normally elevated significantly above grade. Induced by the fans, ambient air then flows vertically through the tube bundles above, condensing the steam within those tubes.

During high winds, the condenser outer shell (wind wall) deflects the ambient air, producing a jet stream below, along the fan inlet region. Jet stream conditions lead to less air flow (suction starvation), reduced pressure, mechanical stress on the fan blades and gear reducers, and increased backpressure on the system, reducing steam-turbine output. An extreme crosswind can mean greatly reduced air uptake, fan stalls, blade damage, and costly motor and gear/drive maintenance and repair.