Introducing a New Turbine Shutoff Capability
TCB Industrial performed the installation of a new 72-inch butterfly valve to serve as the primary turbine shutoff valve for Unit 4 at a hydroelectric powerhouse. Prior to this work, the unit did not have a dedicated shutoff valve, limiting isolation capability during maintenance and emergency conditions.
Structural and Mechanical Modifications
The scope included removal of an existing penstock spool piece, installation of new flanged connections, and placement of a new concrete footing with sole plates to support the valve assembly. Expansion allowances were incorporated using a downstream dresser seal to accommodate thermal and operational movement.
New hydraulic power units and control piping were installed to support valve actuation and monitoring.
Overcoming Access Constraints
The size and weight of the valve exceeded the lifting capacity and clearance of the powerhouse’s existing monorail system. In response, TCB engineered and fabricated a custom elevator system and low-profile transport cart to safely lower and position the valve within the powerhouse.
Result
The valve was successfully installed, tested, and commissioned within the planned outage window. The upgrade significantly improved unit safety and operational control while demonstrating TCB’s ability to engineer solutions for extreme access limitations.
