Planning for your 7F plant’s future? Wondering where your rotor fits in? Penny Leahy continues her blog series on the F-class rotor with a quick rundown of things you should know about GE rotor offerings, as you’re looking to the future.
1. Rotor life management requires a healthy dose of consideration.
Planning for rotor life management begins with a few questions. In my experience these three starting questions are a great way to initiate a dialogue around developing a plan.
-What are the future operational expectations for my unit and/or my plant?
-Should the rotor life management plan encompass an individual unit or extend across a fleet of units?
-What outage constraints, scope, or timing window should be considered?
2. Start planning early…really early
Typically, our partnership with operators is the most successful when we start developing the plan three years before reaching the major outage where the rotor solution will be implemented. The first year revolves around identifying the best option that most benefits the long-term strategy of the plant. The second year is typically spent with customers acquiring various approvals. In the third year GE procures, manufactures, and tests items in preparation for delivery.
Each step is important and may take more or less time depending on the complexities of the situation. To build a quality rotor, steps like rotor forging production and material assessments, machining and assembly of the components, and validation of the assembly, like balancing, are critical.
3. Many operators are developing rotor life management plans over multiple time horizons…are you?
Our most forward-looking customers have a maintenance and rotor life management plan covering multiple time horizons. For example, sometimes their plan exceeds 10 years and cover many outages cycles. Having a rolling 10-year perspective allows better decision-making throughout the lifecycle of the plant. As the industry changes, the recommended solution may change, too.
For example, if renewables are in play, flexibility of the gas turbine and rotor can become key differentiators. Alternatively, if there’s an opportunity to monetize power, increasing power output may be something to consider. When operators share their long-term outlook, a suite of options can be considered. Also, we can plan our new production and the refurbished rotor pool to support operator goals. Speaking of which…
4. Refurbished rotors are unsung heroes in the industry…
Refurbished rotors are often called on in unexpected situations. However, they can also provide an option for rotor life management when a plant has a complex or unknown long-term future. GE refurbished rotors are GE-certified and incorporate the latest technology improvements which can help reduce downtime by improving the delivery cycle of a fully inspected and qualified rotor to site.
Planning brings distinct advantages to operators and GE. For operators it brings a level of outage coordination and decision making which is off critical path and allows for consideration of all options. For GE it brings a level of understanding about the overall fleet needs that helps us stage new production and the refurbished rotor pool. This synergy has shown to be very beneficial in reducing outage stress because we all know other things will come up.
5. It’s a delicate balance.
Rotors are heavily engineered products which require significant time to manufacture, repair, and test. GE wants to ensure we are able to meet the needs of the industry. Planning and execution go hand in hand. To this end, GE is always evaluating our abilities to deliver the quality product operators depend on. With the overall increase in rotor needs across the industry, we use the early planning stages to help meet the overall industry needs. For example, working with our ingot suppliers to have the proper capacity.
6. Materials aren’t immaterial
What’s an ingot? As I touched upon in my first blog, an ingot is the starting point for all metal rotor components. It’s a large piece of metal that is semi-processed into a rough form by pouring liquid metal into a mold. It can easily weigh over 25 tons. Each ingot must be properly shaped and formed by way of forging to ensure the right material properties are present to survive the harsh operating environment of a gas turbine. Forging is followed by a multitude of processes to get to a final production wheel. Only a few material suppliers and processors worldwide can achieve the necessary steel and nickel alloy properties to transform a base ingot into a fully capable F-class rotor wheel.
7. As you start your rotor life management plan, reach out …
Let’s collaborate to find the optimal solution and share learnings from our collective experiences. Know that even if the future is uncertain or not so well defined, we welcome the challenge.
Want more information on GE's Rotor Life Management program for the 7F fleet? Visit our webpage to learn more!
Author: Penny Leahy
Title: Senior Product Manager, Gas Turbine Services at GE Gas Power
Penny focuses on delivering F-class gas turbine rotor solutions. She holds degrees in Mechanical Engineering from Georgia Institute of Technology and Rensselaer Polytechnic Institute. She joined GE Gas Power in 2001, where she’s held roles such as product services engineer, director of performance services, and product line leader.