Machinery Lubrication magazine published by Noria Corporation
Issue link: https://www.e-digitaleditions.com/i/229047
TURBINE LUBRICATION is not enough. Immediate cleaning of the entire interior of the oil system with subsequent turbulent flushing should be performed. Often, if the oil doesn't meet specific requirements, oil replacement (exchange) is also required. Because proper cleaning of an oil system is not easy within an overhaul process or when assembling a new system, a variety of technologies and strategies have been used, such as mechanical cleaning with ramrods, chemical cleaning (with solvents, oil additives, etc.), steam blowing or utilizing different oil flushing procedures. In dirty oil systems, most of these practices do not produce the desired results within a reasonable amount of time and money. Frequently, positive results do not last long but diminish, resulting in the need for additional cleaning. With the cost of operating dirty lubrication systems in turbines far too significant to neglect, more efficient solutions have been developed. One effective method of preparing new oil systems and restoring operated oil systems for future reliable operation involves the technology of hydrodynamic cleaning and flushing of oil systems. This alternative to obsolete or inefficient methods has become a preferred choice of many original equipment manufacturers (OEMs) and power-generation repair companies. The Problem of Dirty Oil Systems One of the most expensive and underestimated problems associated with the use of machinery is the inadequate cleanliness of the oil system. It results in low oil cleanliness, thus leading to most maintenance problems and to related extra expenses (production outages, repairs, penalties and loss of customers). Impurities can enter the oil system during assembly, upon execution of overhauls or simply from the immediate surroundings. They also are created during operation due to oil degradation and corrosion processes. In process machinery, compressed gas often carries different impurities and can interact with the base oil or oil additives while entering the oil system through wet seal glands. These contaminants accumulate in the oil system interiors, creating different deposits. Impurities are the main cause of premature wear and can lead to equipment breakdown. The most vulnerable parts include bearings, hydraulic actuators and controllers, gear- 20 November - December 2013 | www.machinerylubrication.com boxes, drive-shaft seals, pumps, oil coolers, filters and reservoirs. The most common impurities are metal debris from machining, welding slag, sealants or other materials used during assembly or repairs, oil system corrosion products (mainly rust), solid impurities, wear metal particles, and water from oil coolers or steam gland leaks and from ambient humidity. Impurities sometimes A dirty oil pipeline (sludge and include gases (e.g., light corrosion in the return line) hydrocarbons or ammonia) and cooling liquids. Other troublesome impurities involve oil degradation products from aging and thermal stress, which create insoluble chemical compounds that are responsible for varnish and sludge formation. An oil cooler covered by sludge from oil-aging products