Gafr Hydro, Nant Peris

Mechanical refurbishment of a Twin Jet Canyon Turbine on Gafr Hydro Scheme at Ty Isaf Farm, Nant Peris

Project overview

The client reported excessive noise and vibration being produced by the turbine generator in the powerhouse. Upon diagnosis it was found that the vibration was likely caused by miss-alignment, excessive wear on the turbine-generator coupling, generator bearings and the turbine bearings. As a result the hydro scheme was shut down to avoid further damage, but in doing so it no longer produced revenue.

The scope of these works included:

Impact

The Scheme is a 350kw hydro turbine therefore when running it produces a reasonable amount of renewable energy, offsetting carbon and contributing a sizable, diversified revenue stream for the farmer.

The challenge

Once the site team stripped down the turbine-generator they discovered that there was significant wear on the pillow block housings that hold the bearings. There were Issues with the new coupling that had been provided, meaning that the shaft had to be carefully remeasured and tolerance for interference fit specified. The original temperature sensors didn’t fit in the new bearing housings.

Our solution

The team had to use their engineering experience to redesign, modify and overcome the issues. The key was to react quickly in diagnosing the issues and to take the necessary measurements to get replacement parts ordered straight away. With regards to the temperature sensors the team had to think outside the box and locate a spare grease port, that with some modification was able to accommodate an alternative sensor that still provided the same signal to the PLC.