Maintaining reliable and efficient machinery is the aim of the game for gas turbine users operating Australian plants, but all too often expensive reliability issues can be the direct cause of oil degradation.
Fluitec International’s Pierre Vanderkelen spoke to us about the pitfalls of lubrication varnish and the typical symptoms that might indicate evidence of varnish in your machinery.
Informa: What issues do you commonly see as a result of lubricant varnish in Australian operated gas turbines?
Pierre: Our customers experience a wide range of issues depending on multiple factors such as the oil type, the operating conditions and their maintenance practices. Varnish has an iceberg-type of profile: obvious signs are not always there and it is often too late when they materialize. Typical symptoms of varnish would be: abnormal antioxidant depletion, increase of bearing temperatures, sticky valves and let’s not forget visual evidence of varnish in the machine. The associated impacts for the plant range from earlier oil change to mechanical damages and forced outages. There are almost always financial repercussions on the plant’s bottom line. We will present some of these case studies during our presentation at the 16th Australian Gas Turbine Conference.
Informa: What role can condition monitoring tests play in improving machinery efficiency and performance?
Pierre: Oil condition monitoring, especially when performed by experienced labs, should be part of any plant’s standard maintenance practices. Most OEM’s will have their own set of tests. We usually recommend a quarterly sampling/analyses as trending will be one of the guarantor of a reliable interpretation. Another important aspect is the breadth and relevance of parameters tested. We will briefly touch this topic during our presentation.
Informa: What is the most common mis-understood fact about gas turbine varnish?
Pierre: A common misconception is that changing the oil will resolve the varnish issue. This is unfortunately not the case since varnish is a polar contaminant that sticks to the internals of the machine. Changing the oil brings some of these deposits back in solution by mechanisms that we will explain during our presentation. There are different ways to avoid varnish buildups over time as well as to mitigate it. There isn’t a one-fit-all solution and in most cases we do deep RCA (root cause analyses) to better understand the source of the contamination, which guides us to the right set of corrective actions.
Informa: You will be speaking at the 16th Annual Australian Gas Turbines Conference. What are the conversations you are looking forward to having with your peers?
Pierre: To speak frankly most of the presentations look interesting and above all we hope that there will be a lot of interaction and knowledge sharing.
Want to learn more? Pierre will be discussing “Why are gas turbine varnish related events on the rise?” when he joins the expert speaker line up for the 16th Annual Australian Gas Turbines Conference in Sydney on the 25th-26th November.