Another Cool Step For MHPS

Newest model in J-Series air-cooled gas turbine range designed for high output, efficiency and reliability

Mitsubishi Hitachi Power Systems (MHPS) has released the newest model in its J-Series gas turbine line, the M501JAC, an air-cooled gas turbine that is designed to delivers a combination of high output, efficiency and reliability for commercial operations.
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Mitsubishi Hitachi Power Systems (MHPS) has released the newest model in its J-Series gas turbine line. The M501JAC is an enhanced air-cooled gas turbine that is designed to delivers a combination of high output, efficiency and reliability for commercial operations.

The MHPS JAC, which the company said provides a combined cycle output of 540 MW and efficiency exceeding 63%, debuted at the Power-Gen International conference in Orlando, Florida, USA.

“No competitor has demonstrated the reliability of a gas turbine of this size,” said Paul Browning, president and CEO of MHPS Americas. “Mitsubishi Hitachi Power Systems has led the way in ACGT technology and reliability for 15 years by offering proven products with game changing performance.

“And now MHPS is revolutionizing the Advanced Class one more time with an air-cooled J-Series that’s larger and more efficient than any other turbine. Utilities and IPPs around the globe have technically selected seven JAC turbines recently, signaling they recognize that only one turbine on the market today can provide the lowest cost of electricity and the lowest investment risk.”

MHPS said it has already sold 45 steam-cooled J-series turbines, with 21 turbines currently in operation having racked up more than 335,000 hours of commercial operation with 99.3% reliability. The enhanced JAC gas turbine adds an air-cooled combustor to the steam-cooled J-series. This follows up on the company’s steam-cooled and air-cooled G-series gas turbines

To convert the J-series from steam cooling to air cooling, MHPS said modifications were made to the combustor and thermal barrier coatings were enhanced in the turbine section to allow for the higher firing temperature.

At MHPS Takasago Machinery Works in Japan, the highly instrumented T-Point facility conducted full-speed full load testing of the JAC, followed by thousands of hours of reliability verification in commercial operation. The air-cooled version has now accumulated more than 11,000 hours of commercial operation at 99.5% reliability, the company said.

“Our fundamental approach at MHPS is to use a combination of highly instrumented short term testing at different speeds and loads, followed by long-term reliability verification at T-Point before we release a first of kind product enhancement,” said Akimasa Muyama, head of Turbine Products Headquarters for MHPS. “This differentiates us from other turbine manufacturers.

“There are a number of potential reliability issues, such as creep, low cycle fatigue and thermal barrier coating deterioration that require thousands of operating hours before they start to become apparent. We’re the only turbine OEM to have research and development, design, manufacturing, short term performance testing and long term reliability verification in a single location. That’s why the G-series is so successful, and why the J-series is the most reliable gas turbine in the world.”

MHPS JAC units are being built and shipped from the Savannah Machinery Works in Georgia, USA, as well as the Takasago Works in Japan. The JAC maintains the long standing features of a compressor shaft end drive, two-bearing rotor structure, axial flow exhaust, bolt-connected discs with torque pins on the compressor rotor and curvic couplings on the turbine rotor discs. When turbine servicing is required, horizontally split casings help facilitate field removal of the blades and vanes with the rotor in place, the company said.

MHPS J-series turbines are digitally enabled, designed to provide customers with real-time adaptive control and actionable knowledge by utilizing sensor and control system data, the company said, helping optimize plant performance, avoid unplanned downtime and enable predictive maintenance.

“We’re enabling the power plant of the future,” Browning said. “The latest JAC is further proof of the reliable approach MHPS brings to creating a brighter future.”