Turbine Testing

Since 1999, ILD Inc. has been the authority on off-critical path small steam turbine overspeed testing. Two series of devices are currently in service in nuclear power stations across the United States as well as Japan. The key advantage afforded by both devices is the operator’s ability to negate the use of process steam or compressed air during required turbine overspeed testing. The ease of use and removal from the critical path allows the completion of overspeed tests during one shift at any time during operation or unit shutdowns. The ILD Terry Turbine Overspeed Device (TTOD) and its operating methods are accepted by EPRI/NMAC in their Terry Turbine Maintenance Guides. ILD’s systems are suitable for overspeed testing of auxiliary turbines associated with Reactor Core Isolation Cooling (RCIC), Auxiliary Feedwater (AFW) and Emergency Feedwater (EFW) systems, as well as larger High Pressure Coolant Injection (HPCI) systems. The TTOD has provided successful support in testing of Terry GS-1, GS-2 and ZS-4 turbines, as well as equivalently sized Worthington and Elliot turbines. The Turbine Controls Test Device offers the ability to test both the aforementioned small turbines in addition to Terry CS and CCS turbines.

Terry Turbine Over-speed Test Device™ (TTOD)

Overspeed Trip Test Device for Steam Turbines < 750 HP

The Terry Turbine Overspeed Device (TTOD) is comprised of proprietary logic control systems coupled to a variable frequency drive, which is all conveniently mounted on a heavy duty cart for easy transport. Monitoring and control functions implement solid state controls, which ensure longevity of equipment as well as pre-programmed user defined interlocks for positive control at all times. The TTOD powers a three-phase alternating current motor that is mechanically coupled to the turbine to be overspeed tested by one of two methods: the ILD Half Coupling Drive Adaptor (HCDA), or the ILD RCIC/AFWTransfer Case.

Half Coupling Drive Adaptor

The HCDA provides an economic power transmission solution which uses only the turbine end half coupling as an attachment point. A synchronous drive belt and pulley system provides a simple connection between the HCDA and the TTOD motor. All new HCDA units are manufactured from a single AISI 4140 pre-heat treated billet and case hardened to a Brinell hardness of at least 370. There are multiple units across the United States and Japan using ILD HCDA units on their Terry or equivalent turbines, with several more planned or under construction.

Transfer Case

The ILD RCIC/AFW Transfer Case provides a more consistent and maintenance free testing apparatus in comparison to the HCDA. While using the same synchronous belt and pulley system implemented in the HCDA, the transfer case is shipped pre-tested and documented such that no maintenance on the transfer case itself is necessary throughout its lifespan. The ILD Transfer Case provides a solid mounting point both at its motor mounting plate as well as on the pump half coupling of the turbine to be tested, resulting in reduced vibration and radial loading on the turbine shaft. The transfer case fully encloses the synchronous drive belt system for increased operator and spectator safety during overspeed trip testing.These characteristics provide for exceptional repeatability and increased ease of setup and take-down of testing apparatus, all while maintaining consistent and proper turbine shaft bearing temperatures.

Turbine Controls Test Device™ (TCTD)

Overspeed Trip Test Device for Steam Turbines > 750 HP

Building on the tremendous success of the ILD Terry Turbine Over-speed Test Device™, ILD has developed the next generation of scalable turbine controls testing equipment, the Turbine Controls Test Device™ (TCTD). The TCTD incorporates ILD’s patented technology to allow larger auxiliary turbines, such as HPCI turbines and feedwater pump turbines, to be over-speed tested without steam, saving costly outage time.

HPCI Transfer Case

The TCTD implements a larger transfer case for BWR HPCI Terry CS and CCS turbines. The HPCI transfer case is designed by Emerson Power Transmission Corporation with quality in mind. It is constructed from mild steel for strength and safety for overspeed trip testing of larger steam turbines. This transfer case implements a high velocity steel chain similar to that of an automotive timing chain for strength and durability, making it suitable to meet the demands of HPCI system turbines. Five units in the United States currently own TCTD and HPCI Transfer Case devices for the overspeed testing of their HPCI systems.