To ensure the safe and reliable operation
of steam turbine generator sets, the function of steam turbine oil is very
important. So it must have the performance that can meet the following aspects:
(1) The viscosity of the oil can be
maintained within the specified operating temperature range and the oil quality
(2) It can ensure that all lubricated parts
form a thin oil film, minimize friction, resist wear, and extend the safe
operating life of the equipment.
(3) Through the oil circulation, the heat
generated by the journals, bearings and other heat sources can be transferred
to the oil cooler for cooling through the oil.
(4) Because the lubricating oil runs under
non-sealed conditions, it must be able to resist oxidation and deterioration in
the presence of air, water, hydrogen and high temperature environments.
(5) It can inhibit the generation of
bubbles and entrained air.
(6) The water entering the lubrication
system can be separated quickly and discharged from the bottom of the oil tank.
(7) It is also necessary to protect the
quality of equipment components from corrosion and rust.
(1) Temperature. It has a great influence
on the oxidation reaction speed, and the reaction speed increases when the
temperature rises. Generally speaking, the influence is greater when the
temperature is above 60℃. At this time, the oxidation speed will double for every 10℃ increase,
that is, the oxidation speed at 70℃ is 60℃ At 80°C, it is
twice as high as at 70°C, which is 4 times as much as at 60°C. Lubricating oil
has a thermal load during operation. Different units and different operating
conditions (such as whether the unit is running at full load, etc.) produce
different heat, and the temperature rise of lubricating oil is also different
(that is, the thermal load is different), and the heat load is different. It
will be uniform, and there will often be local "hot spots" in the
lubrication system, which will accelerate the oxidation process of the oil and
cause thermal oxidative deterioration.
The oil will crack at high temperature,
forming unstable compounds, which will be further polymerized into various
resins and sludge. Above 100°C, the sludge will be carbonized to form a
coke-like mixture, which is more harmful.
(2) Contamination. Same as transformer oil degrades, moisture, metals and
particulate matter are very important contamination in turbine oil during the long term operation. Their presence will promote the deterioration of oil
quality and also contribute to the formation of foam, fouling and sludge. And
these impurities quickly enter the running turbine oil. In operation, the
turbine oil contains more or less impurities, so pay attention to timely
(3) The structure and design of the oil
system also affect the rate of deterioration of oil quality. Such as an oil
tank, it is not only a reservoir for all the oil in the lubrication system, but
also can separate the air, moisture and impurities in the oil from the oil
during the residence time in the tank. Therefore, the structural design of the
fuel tank (such as the size of the volume, the location of the components in
the tank, the flow route of the oil in the tank, etc.) has a certain influence
on the deterioration of the oil quality. For example, if the design of the fuel
tank volume is too small, the oil staying time in the tank will be reduced, the
number of cycles (same time) will be more, the precipitation of impurities from
the oil and the demulsification time of emulsified oil will be shortened, and
the result will be no separation or separation of air, moisture, etc. If the
separation is not good, a part of it will continue to circulate in the oil
again, which will accelerate the deterioration of the oil. Secondly, the oil
pressure and flow rate are also related to the deterioration of oil quality.
The oil in the oil inlet pipe should maintain a certain pressure and flow rate
(about 1.5~2m/s). There is no pressure on the oil in the oil return pipe, and
the oil flow rate must be small (about 0.5~-1.5m/s) to avoid splashing of oil
in the oil tank, forming foam, causing residual gas in the oil, and
accelerating the deterioration of oil quality; at the same time, the flow rate
is large, which may make the oil tank When the oil is stirred vigorously, the
water-containing oil may become emulsified and accelerate the deterioration of
(4) Radiation. This is mainly for nuclear
power plants. The degree to which the steam turbine oil in nuclear power plants
is affected by radiation depends on the composition and additives of the oil
itself. Alkanes and cycloalkanes are more affected than aromatic hydrocarbons.
After radiation, the C-C and C-H bonding bonds are split, and H2 can be released
at the same time. The release amount is less. As the composition changes, of
course the physical and chemical properties and lubricating properties of the
oil also change. The prominent reaction is: gas evolution, increased viscosity,
reduced corrosion resistance and oxidation stability, increased acid value,
darker color, sludge, unpleasant odor compounds, and decreased flash point. But
generally speaking, the above phenomenon will only occur when the radiation
dose is greater than 106J/kg.
(5) Internal factors: the chemical
composition of oil. It is a mixture of hydrocarbons. The relative proportions
of paraffinic diameter, naphthenic hydrocarbons and aromatic hydrocarbons in
the base oil are different, and the physical properties such as viscosity index
and pour point are also different; aromatic hydrocarbons affect the stability
of the oil and its structure and in the oil. The content is related, so when
new oil is generated, it is often taken to increase the depth of base oil
refining, reduce harmful substances in the oil, and add additives to improve
the quality of the oil. However, the compatibility of additives has a certain
effect on oil stability. Therefore, if the additives are not well selected, it
will be counterproductive and make the oil performance worse. Therefore, a
small test should be done before adding.
6) The quality of oil system maintenance is
not good, especially the pipelines of leaking units. There are often rust,
emulsion, sediments, etc. in the oil. If the maintenance cannot be completely
removed, the quality of the oil will definitely be reduced. For example, when
cleaning the pipeline, in addition to mechanical methods, cleaning agents such
as washing powder should be used, and more attention should be paid to
cleaning, and there should be no residual cleaning agent, otherwise it will
contaminate the oil and accelerate the deterioration of the oil.
PureTech Oil Filtration provides you with following equipments which are suitable for turbine oil treatment:
And among above Turbine Oil Purifiers, the thermal-vacuum turbine oil purifier is most widely used in power generation companies. It can work online and perform 24 hour online oil cleaning service. What's more, with thermo-vacuum technology, the water content in turbine oil will be reduced to lower than 50 ppm after purification.
Welcome to contact PureTech Oil Filtration for more information about steam turbine oil filtration. And if you want to know transformer oil filtration or other oil filtration plants, please visit our website.
PureTech Oil Filtration | www.cqpuretech.com | firstname.lastname@example.org | +8617815389416
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