Summary
Combined cycle and conventional steam plants are being asked to start more often, cycle harder, and sit longer in hot standby than their original designs anticipated. Many of the equipment failures that follow trace back not to the metal itself but to how the plant is configured, instrumented, and controlled. Undetected water collecting in an offline heat recovery steam generator or motive steam line, for example, can set up water hammer or steam turbine water induction the next time the unit comes online. Structural Integrity Associate’s (SIA’s) Gas and Steam Plant Operability Assessments are designed to find those risks before they become damage.
Each assessment is custom tailored and takes a whole-plant view, covering steam turbine generators (STGs), gas turbine generators (GTGs), heat recovery steam generators (HRSGs), high energy piping (HEP), and critical balance-of-plant components. Depending on the plant’s needs, SIA’s multidisciplinary team identifies operating risks, determines the cause of equipment damage that has already occurred, and recommends changes to operating procedures, control logic, and equipment design.
The work begins on site with an equipment and controls orientation, operator interviews, a walkdown against Piping and Instrumentation Diagrams (P&IDs) or the as-built configuration, and a physical review of control system cabinets. The team collects P&IDs, O&M manuals, control logic and schematics, operating procedures, electrical one-line diagrams, Management of Change records, and maintenance history. Engineers then review equipment configuration and site historian data for startups, shutdowns, load changes, steady-state operation, hydraulic trips, STG-to-GTG operating transitions, and overspeed testing when available. A controls review examines startup, shutdown, trip, and overspeed protection logic, along with the plant’s alarm management program and quality assurance effectiveness. The final phase evaluates how protection and continuous control logic is physically implemented, from instrument installation and calibration settings to hard-wired logic and instrumentation redundancy.
The result is a clear picture of where configuration, controls, and operating practice put equipment at risk, with recommendations that help operators optimize equipment life, reduce unplanned outages, and improve operational safety. Findings connect directly to SIA’s broader turbine and generator services, including root cause investigation in the Metallurgical Laboratory and online attemperator and water induction monitoring through PlantTrack™, so risks identified during the assessment can be tracked long after it is complete. Contact SIA to scope an assessment for your plant.