Zeballos Lake Refurbishment Project

Statistics:

During trip tests, the runner was destroyed by foreign objects that came through the penstock. The surfaces of the wicket gates on the runner side as well as the head cover and discharge ring close to the runner inlet were also damaged. The damaged parts are shown in the pictures below. The damaged areas on the head cover and discharge ring were built up by welding and then machined to finish. The runner blade inlet edges were machined to remove the damaged sections. Then each blade was restored by welding a piece of stainless steel plate to the machined inlet edge followed by grinding and polishing to finish. The finished runner was checked for dynamic balance. The wicket gates were ground to remove most of damaged areas. Larger dents and gouges were welded, ground and polished to finish. A new set of wicket gate bearings was also supplied.

Damaged Headcover