Criteria for Assessing the Quality of Fire-Resistant Fluids

To date, in the regulatory and technical documents containing requirements for the quality of fire-resistant fluids, there is no unified concept of the rejection indicators of oil, upon reaching the limit values of which the use of the oil is prohibited. In this regard, difficulties arise in making decisions about extending the service life of fire-resistant fluids. Some facilities use oils with an acid number of 3 mg KOH/g and higher, which significantly reduces the reliability of the oil-filled equipment of the power plant, up to the development of emergency situations. The article examines in detail the processes of destruction of fire-resistant fluids based on triaryl phosphates and the conditions for phosphating metals. The results are presented from studies of the surfaces of steel plates after conducting an analysis to determine the corrosion properties of oils in accordance with FR.1.31.2010.08899 Methodology for Measuring the Anticorrosion Characteristics of Samples of Mineral and Fire-Resistant (type OMTI) Turbine Oils (certificate of certification no. MVI 60-09 dated November 17, 2009). It has been shown that, when using oils with a maximum acid number, a film consisting of iron phosphates is formed on the surface of steel coupons, with the simultaneous occurrence of a polycondensation process of oil-decomposition products. Taken together, this leads to an incorrect definition of such an oil quality criterion as corrosion on steel plates. The results of studies of deposits taken from various units of the turbo unit lubrication system are presented, indicating an inevitable decrease in the reliability of the oil system when using oil with a high acid number.