MHI has successfully completed work on the KOSEP (Southeast Korea Power Company) YEOSU Power Plant #2 steam turbine generator system equipment replacement project (Capacity after new equipment installed: 328.6 MW) and final delivery to the customer has been completed within the scheduled period.

At the time of the test operation phase, after the entire system had been delivered, the performance surpassed the guaranteed level and this high performance and high reliability steam turbine generator system equipment met the customer's expectations.

This difficult project, to meet the customer's needs, involved replacing a 4 casing steam turbine, generator and some boiler feed water heater system made by another manufacturer with a new MHI 3 casing steam turbine and other equipment. A diamond wire saw, as a new method, was used to cut away the top deck part of the turbine foundation and this approach helped to shorten the time required for the project.

MHI will continue to provide turbine generator system upgrading and replacement project services ever for other manufacturer's equipment in order to meet customer needs.

• Reconstruction of turbine foundation
In a case where both the equipment model and the number of casings of the turbine to be replaced differ from the equipment that will replace it, the configuration of the foundation and the embedded metal parts must be changed so that changes must be made to the foundation upon which the turbine sits.
In this situation, an inspection of the viability of the existing turbine foundation and the degree of correspondence of the existing turbine foundation and the new turbine foundation is carried out. The usual approach is that any part that extends beyond the mat base (See the diagram below) is removed before the installation of the new equipment begins.
However, the removal and replacement of concrete structures causes a high level of vibration, noise and dust in the vicinity of the work. In the case of the project described above, where the work area was surrounded with many pieces of equipment and it was important to carry out the work as rapidly as possible, only the existing top deck was removed and replaced by a new deck. To remove the existing deck rapidly, a method involving the use of a diamond wire saw applied.
The figure below shows the portion of the turbine base foundation that was replaced

1. Existing machine dismantling 2. Removal work of foundation 3. Construction of new foundation 4. New machine installation

Before replacement Removal of the base After replacement