The stainless steel flue cappings on top of one of the main exhaust stacks at Victoria’s largest Power Station Loy Yang Power were suffering from extremely corroded cappings stiffeners and windshields. Absafe Pty Ltd. won a select tender to complete this work to Loy Yang Power’s specification.
This required significant welding and repair works followed by application of a high temperature tolerant paint system.
One of the main problems with this project was that all of the welding, blasting and coating work needed to be undertaken whilst the flue was active. This work needed to be completed on a very tall slender structure that is over 260m high (~70+ storey building) which is also located in a very exposed location. To re-instate the structural integrity of the flue capping a new set of stiffeners around the circumference of the capping needed to be welded in. Depending on the measured depth of corrosion and pitting a number of plates were required to be replaced.
The pitting of the capping was irregular, being far more severe where it faced the prevailing wind and the nearby cooling tower. The degradation was concentrated on the raked upper surfaces which illustrates the corrosive effects of the flue gases in combination with other local environmental effects such as local weather patterns.