1. Lubricating system cleaning methods.
At present, to remove post-operational contaminants (deposits), the following methods are applied:
- The chemical removal of oil ageing products (without eliminating ferrous oxide deposits) and then the washing
of the entire oil system. This technology's drawback is that it is impossible to remove corrosion products from
pipeline surface.
- The chemical cleaning of oil system by tempering and etching with mineral acid solutions. Applications have
not yielded the desired technical results in several applications. When using oils in turbines cleaned this way,
it has been observed that contaminants occur for a long time with the dominance of hydrated ferrous oxides.
If orthophosphoric acid is used, it has been noticed that black contaminants increase in oil, which proves that the
formed phosphorus-ferrous layer loosens from the surface, which also deteriorates the working conditions of
abrading nodes.
- The mechanical cleaning of oil system elements (cleaning rods and cleaning agents). This method, apart from
immense labour-consumptiveness, results also in major cleaning inefficiency and should not be used on important
machinery and equipment.
- The hydrodynamic removal of contaminants and deposits and then the washing of the entire system with oil at
high flow speeds at the same time filtering it fully is a technology that is attaining rising popularity.
Comprehensively connected hydrodynamic loosening and contaminant washing with properly matched pumping and
filtering units is a method, which does not destroy protective (magnetite) layers formed on pipeline surfaces.
As a result, we achieve very high cleanliness of the oil operated in a turbine and very low wear of filters
when operating the equipment.
The above statements allow to draw a conclusion that the hydrodynamic cleaning of operated oil systems
is the most efficient and safest method that is characterised by the minimum advancement of corrosion. It is also
the most effective method of overhauling the system oil in sets of turbines operated for many years.
According to statistics run at the end of the 80's in the USA, the technology consisting of the combination
of high-pressure water spray and high-flow-rate washing is faster and more productive than other conventional
methods. When washing in normal conditions (e.g. using stationary pumps from the system), impurities may appear
endlessly (if proper flow turbulence stimulation is not ensured, all impurities cannot be removed).
In the method described above, contaminants are directed immediately towards filters of the external
pumping and filtering unit with high flow rate and it allows to obtain excellent results within the time
shorter than 120 hours. Find details on the hydrodynamic cleaning of oil systems in the offer.
