Beijing Quansan Energy Technology Co., Ltd. was the first to carry out energy-saving retrofit work on domestic steam turbines from the early 1990s, and applied full 3D technology to the steam turbine flow design. In October 1996, the first 200MW steam turbine retrofit design was completed in China, and the results passed the national appraisal.
Starting from the flow design of 200MW units in early production, the technology has been applied to the transformation of domestic 300MW, 125MW, 100MW, and 50MW units, so that the main steam turbine products below the subcritical level in China have adopted advanced multi-stage steam turbines. Pneumatic thermal design system, and it is fully used in the design of the flow passage of high, medium and low pressure cylinders of steam turbines. Under the premise that the size of the turbine body structure is unchanged, the heat consumption value of the unit is greatly reduced by replacing the stationary blade (baffle) and moving blade (rotor). In terms of structural design, a number of measures have been adopted such as moving blades with their own shrouds, connection of the entire circle, elimination of stiffeners, change of cast iron partitions to welded steel partitions, and reasonable adjustment of dynamic and static gaps. Unit operation efficiency and safety and reliability have been greatly improved.