Author Archives: Khashayar Hajiahmad

Should We Trust the Turbine OEM “with Closed Eyes” on Oil-Related Issues? In turbomachinery, the OEM deserves respect. The OEM designed the turbine, selected the bearing arrangement, calculated the clearances, defined the lube-oil system requirements, approved the oil type, and established the maintenance philosophy. So, when the subject is machine design limits, warranty, bearing geometry, control-systemContinueContinue reading “Should We Trust the Turbine OEM “with Closed Eyes” on Oil-Related Issues?”

Mechanical faults in turbomachinery that make oil varnishing happen faster In turbomachinery, varnish is usually not caused by one single “bad oil” event. It is a deposit-forming failure mode where turbine/compressor oil degrades, forms polar oxidation or thermal-degradation by-products, reaches its solubility limit, and then deposits on cooler or sensitive surfaces such as bearings, servo valves, filters,ContinueContinue reading “Mechanical faults in turbomachinery that make oil varnishing happen faster”

What Happens to Turbine Oil When Drums Are Stored Under the Sun Turbine oil is designed to operate in demanding machinery, but it is still a chemically active lubricant. It is usually made from a highly refined base oil plus performance additives such as antioxidants, rust inhibitors, demulsifiers, foam-control additives, and sometimes anti-wear or deposit-controlContinueContinue reading “What Happens to Turbine Oil When Drums Are Stored Under the Sun”

Below is a 100-question technical checklist for a turbine engineer. My wording is direct: if the engineer cannot answer these questions with data, trends, limits, and evidence, he cannot reliably estimate turbine oil health or remaining useful life. A proper turbine-oil life estimate must combine oil identity, operating duty, sampling quality, lab method, contamination, oxidation, additive depletion, varnish risk,ContinueContinue reading “100 Questions Every Turbine Engineer Must Answer”

Turbine Engineer asked Khash: MPC measures color intensity but Varnish can be not colorful but present How to do the analysis of MPC test correctly ? MPC near Zero is the best ? Khash answered: Yes. This is one of the biggest misunderstandings about the MPC test (ASTM D7843). MPC does not directly measure varnish mass.ItContinueContinue reading “MPC measures color intensity but Varnish can be not colorful but present”

100 Right & Wrong Turbine Oil Maintenance Actions Turbine oil does not suddenly become “bad.”It usually becomes bad because of many small wrong actions repeated over time. The oil starts clean.Then comes water. Dirt. Heat. Oxidation. Varnish. Sludge. Foaming. High wear. Bearing problems. Trips. And one day, the turbine oil is crying. The good news?WithContinueContinue reading “100 Right & Wrong Turbine Oil Maintenance Actions”

How Training in Machinery Lubrication Improves Turbomachinery Lubrication Practices Introduction Turbomachinery lubrication is not just “putting oil in a machine.” For turbines, compressors, turbo-pumps, gearboxes, expanders, generator bearings, seal-oil systems, and control-oil systems, lubrication is a reliability barrier. The oil must create the correct film thickness, remove heat, prevent corrosion, carry contaminants to filters, separateContinueContinue reading “How Training in Machinery Lubrication Improves Turbomachinery Lubrication Practices”

Why Electrostatic Filtration Fails in Oils with High Acid Number and High Water Content Electrostatic oil filtration is effective only when the oil behaves like a good electrical insulator. In a healthy hydraulic, turbine, transformer, or circulating oil system, the base oil has relatively low conductivity, so a strong electric field can be maintained acrossContinueContinue reading “Why Electrostatic Filtration Fails in Oils with High Acid Number and High Water Content”

Antioxidant Additive Packages in Turbine Oils: Phenolic, Aminic, and Mixed Systems Key point upfront In formal lubricant chemistry, phenolic antioxidants and aminic antioxidants are both usually “primary antioxidants” because they mainly stop free-radical chain oxidation. A true secondary antioxidant is normally a peroxide decomposer, such as a phosphite, sulfide, dithiocarbamate, sulfurized phenol, or ZDDP-type chemistry in fluids where zincContinueContinue reading “Antioxidant Additive Packages in Turbine Oils: Phenolic, Aminic, and Mixed Systems”

Khash was asked: What is Babbitt ? Can’t its material to be designed to attract less varnish ? discuss in details how these metals attract varnish and what changes are required to attract less , is it possible to coat them or have a metallurgy that is less polar ?  Khash Replied: 1. What BabbittContinueContinue reading “Designing Bearing Surfaces for Less Varnish”