Heavy-duty gas turbines have been referred to as the “crown pearl” of the equipment manufacturing industry, due to the very limited number of countries able to independently produce them over the past several decades. These nations were previously largely limited to the US, Japan, and Germany.
Recently, a comprehensive load test was completed for the “Class-F 50 Megawatt Heavy-Duty Gas Turbine” major national technological innovation and industrialization project. The MTG470F high-speed gearbox independently developed by Nanjing High Speed & Accurate Gear (Group) Co., Ltd. (NGC) served as a core component of the tested heavy-duty gas turbine. During the operations of the test, all of the high-speed gearbox’s indicators, including vibration, temperature increase, and stability, all reached internationally leading standards. This achievement highlights the technological advantages that NGC has continuously developed in the field of high-speed drives and its increasing and steady pace of innovation and development.
Assuming Heavy Responsibilities with Rapid Delivery
The independent research and manufacture of 50 MW Class-F heavy-duty gas turbine serves as a major technological innovation and industrialization project for the Chinese state. At a key project stage, NGC assumed the heavy task of developing and manufacturing the high-speed gearbox, the core drive system for the full-power load test of this national project. Beginning with the acceptance of the project in January of 2020 to the delivery of the device in April, the full length of time elapsed from research to manufacturing to delivery only took three and a half months. This fully manifested NGC’s corporate spirit of “climb up the summit step by step, strive for perfection bit by bit”, as well as its outstanding international competitiveness.
Making Bold Innovations in Pursuit of Perfection
During its test, the Class-F 50 MW heavy-duty gas turbine had to be started up frequently. The high-speed gearbox needs to bear force on both sides during these frequent starts, which were conducted under varying working conditions and high-amplitude external stimulus input during the acceleration test.
The MTG470F high-speed gearbox adopts an innovative coaxial layout design to achieve more balanced load distribution. Through brand-new modifications and the application of advanced technologies, key technical issues have been resolved in terms of providing cross-support to the high-speed rotor. This unique rotor stabilizer technology has met the usage requirements for operation under extreme working conditions, and can guarantee that the entire drive system runs reliably and stably.
Precision Manufacturing Produces Outstanding Performance
With the support of advanced manufacturing technologies such as high-precision gear processing, dynamic balancing of composite axes, and precision control of large-scale gearboxes, all parts and components totally meet the quality requirements for turbine usage. After assembly, it has passed the entire test in a single round, with each performance indicator reaching the design requirements.
Under the conditions of installing extra-long spans, the coaxiality between the equipment’s input axis and output axis remains smaller than 0.02 mm. With the addition of the high-precision connections at the axis ends, seamless connections have been ensured for the entire system, so installation can be completed in a single stage.
Excellent Application Performance
The MTG470F high-speed gearbox was installed and commissioned at the customer site at the end of April of 2020, and resulted in the smooth completion of the heavy-duty gas turbine’s load test. For more than four months since the turbine was put into operation, each of its performance indicators, including vibration, temperature increase, and stability during accelerated loading, all met the system’s operating requirements and reached an advanced performance level compared to similar products from around the world, and won high recognition from its users.
After more than 50 years of technical and organizational refinement and development, this company built around the creation of high-speed gearboxes has grown into a champion enterprise in this challenging and specialized sector of the manufacturing industry (Ministry of Industry and Information, 2017-2022) and a highly influential enterprise in China’s gear industry (Gear and Electric Drive Branch of China Machinery Component Association, 2019). NGC will continue to uphold its mission of promoting high-quality development of advanced equipment manufacturing, put the utmost effort into the field of high-speed drives, promote technological progress in the industry, and provide its customers with superior high-speed drive solutions and comprehensive services.