Transformer oil is a mineral based oil that is commonly used in transformers for its chemical properties and dielectric strength. This oil in your transformer acts
as an insulator and a cooling agent
. Over time, the oil will degrade resulting in the potential for faults and costly repairs.
Which oil is used in transformer?
Mineral oil and Synthetic oil
are the majorly used transformer oil. These are the petroleum products, like Naphthenic based transformer oil and Paraffinic based transformer oil. Naphthenic based transformer oils are known for their heat distribution, which is one of the main problems with transformer.
What is the importance of transformer oil in transformer?
Transformers are used by the electrical industry to transfer electrical energy from one circuit to another. The oil surrounding the coils in a power transformer
provide cooling, insulation and protection against corona and arcing
.
What is mineral insulating oil?
Abstract. Mineral insulating oil (MIO) is
the most widely used fluid for electrical insulation and heat transfer in the power industry
. EPRI has recognized the utility need for data on the chemical composition and physical properties of new and used MIOs.
What fluid is in electrical transformers?
Today, most transformers are filled with
mineral oil
. This has been the case since the late 19th century, when chemist Elihu Thomson, whose company later merged to form General Electric, patented the use of mineral oil in transformers to help disperse heat from the core of a transformer in order to prolong its life.
Is mineral oil dielectric?
Petroleum-based mineral oils have been used for liquid insulation in high voltage equipments since long time ago because they have
excellent dielectric properties
such as high electric field strength, low dielectric losses and good long term performance.
Which gas is used in transformer?
Typical gases that appear in transformers are
hydrogen (H
2
), methane (CH
4
), ethane (C
2
H
6
), ethylene (C
2
H
4
), and acetylene (C
2
H
2
)
. These gases begin to form at specific temperatures and dissolve within the insulation oil of a power transformer, as shown in Figure 1.
Is transformer mineral oil flammable?
The temperature of the mineral oil inside the transformer tank increases, forming
flammable vapour
that is suddenly released from an opening in the tank into the surrounding atmosphere. Although the probability of transformer fires and explosions is relatively low, it is not negligible.
Why do we check oil in transformer?
Why is Transformer Oil Testing Important
Identify if a certain oil is suitable for future use
.
Detect whether regeneration or filtration is needed
.
Reduce oil costs and enhance component life
.
Prevent untimely failures
and maximize safety.
What is sk value of transformer oil?
S K Value is
an index of degree of refining of oil measured by the reaction of oil sample with a volume of concentrated
sulphuric acid. S K value measurement method was covered in Annexure D to IS:335 ‘Method of Determination of SK Value’.
What is PCB transformer oil?
Polychlorinated biphenyls (PCBs) are
persistent organic pollutants in insulating oil of a large number of transformers
. A rapid and economical analytical method to detect PCB contamination is still required. … PCBs in the pretreated oil were measured using a microfluidic kinetic exclusion assay.
What are the properties of mineral oil?
Some of the key mineral oil properties include (a)
viscosity
, (b) oxidative stability, (c) volatility, (d) solvency, (e) pressure-viscosity coefficient, (f) pour point, and (g) color. Viscosity is the single most critical mineral oil property.
Is transformer oil mineral oil?
Transformer oil or insulating oil is an oil that is stable at high temperatures and has excellent electrical insulating properties. … Transformer oil is
most often based on mineral oil
, but alternative formulations with different engineering or environmental properties are growing in popularity.
What is viscosity of transformer oil?
High quality transformer oils are normally in the range of
7- 8 mm2/sec at 40°C
and even with such low viscosity, they still meet the requirement for flash point (<135°C) from the same standard.
What is Type 2 mineral oil?
Type I mineral oils are used for apparatuses where normal oxidation resistance is required, where as, Type II mineral oils are
used for apparatuses where greater oxidation resistance is required
.
Is transformer mineral oil biodegradable?
Mineral oil used in transformer for insulation is hazardous for environment because of its
non-biodegradable nature
. This paper explores possibilities of replacing mineral oil by fluids with better characteristics.
Why is castor oil used in capacitors?
Abstract: Several new liquid impregnants for capacitors have been suggested as possible alternatives to PCB’s which are being replaced in view of their harmful effects. … This paper gives a detailed analysis of the
dielectric behavior
of the oil alone and all-paper capacitors impregnated with castor oil.
What is Rogers ratio?
Rogers Ratio Method
compares quantities of different key gases by dividing one into the other
. This gives a ratio of the amount of one key gas to another. … Rogers used these relationships and determined that if a certain ratio existed, then a specific temperature had been reached.
Why dielectric is used in EDM?
Dielectric is an important parameter in EDM and plays a
crucial role in determining high material removal rate (MRR) and surface finish during operation
. The dielectric fluid behave as a medium which controls the electrical discharge and absorb heat during process.
Why nitrogen is filled in transformers?
To put out the fire in a transformer, were it to occur, we
can reduce the oxygen level by displacing it with nitrogen
gas. … The nitrogen pressure in the transformer also helps to reduce the top oil pressure and temperature which is critical for preventing an explosion.
What is DP in transformer?
DP means
distribution panel
in a power supply system. … DP in the power supply system is different from the transformer, which can be called by different names according to construction, voltages, applications, cooling methods, etc.
What is the Colour of transformer oil?
Generally, oil that is
yellow, orange, or even somewhat red in color
is fresher and will work as intended. As oil ages, it transforms to a brown or black color and its efficacy diminishes.
Is transformer mineral oil Hazardous?
It’s also
highly flammable
. If a transformer were to leak mineral oil, it could easily start a fire. … And although mineral oil is relatively more benign than PCBs, it’s nonetheless an environmental contaminant that requires careful hazardous material removal.
What is the flashpoint of mineral oil?
Flash point:
135C (275F)
CC Autoignition temperature: 260 – 370C (500 – 698F) Combustible Liquid and Vapor!
What is crackle test of transformer oil?
The crackle test is a
standard laboratory test to detect the presence of water in lubricating oil
. A drop of oil is placed on a hotplate that has been heated to approximately 400° F. The sample then bubbles, spits, crackles or pops when moisture is present.
What is DGA test for transformer oil?
Dissolved gas analysis
(DGA) is an examination of electrical transformer oil contaminants. Insulating materials within electrical equipment liberate gases as they slowly break down over time.
What IEC 60296?
IEC 60296:2020 provides
specifications and test methods for unused and recycled mineral insulating oils
. It applies to mineral oil delivered according to the contractual agreement, intended for use in transformers, switchgear and similar electrical equipment in which oil is required for insulation and heat transfer.
Is code of insulating oil?
HS Codes
27101985
: HS Classifcations of Insulating oil for transformer and circuit breaker (transformer and circuit breaker oils) conforming to standard IS 335 or IS 12463.
Which liquid is used for transformer cooling?
Oil-insulated transformers use
mineral oil
for cooling. This oil is thin enough to circulate freely and does a good job of providing insulation between the transformer windings and the core. It is however subject to oxidation and if any moisture enters the oil, its insulating value is substantially reduced.
What is acidity test of a transformer?
The acidity of insulating oil is generally measured by
the required quantity in milligram of KOH to entirely neutralize the acidity of a specific quantity in gram of the oil
. Acidity of an insulating oil is 0.3 mg KOH / g means 0.3 milligram of KOH is required to neutralize 1 gram of that insulating oil.
What is BIS specification of transformer oil?
| Sr.No. Test Properties Specification | 1 Appearance The oil shall be Clear & Transparent & free from suspended matter or sediments | 2 Density @ 29.5, °C, Max 0.89 g/cm 3 | 3 Viscosity, Kinematic | a) at 27°C, cSt 27.00 |
|---|
Why was PCB used in transformers?
PCBs have been used as coolants and lubricants in transformers, capacitors, and other electrical equipment because
they don’t burn easily and are good insulators
. The manufacture of PCBs was stopped in the U.S. in 1977 because of evidence they build up in the environment and can cause harmful health effects.
Does mineral oil contain PCB?
Electrical insulating mineral oils in a number of transformers contain measurable amounts of
polychlorinated
biphenyls (PCBs). An EPRI project investigated four possible approaches for removing PCBs from contaminated mineral oil.
What are the qualities of good transformer oil?
Synthetic transformer oil like chlorinated diphenyl has excellent properties like
chemical stability
, non-oxidizing, good dielectric strength, moisture repellant, reduced risk due to fire and explosion.
Why is it called mineral oil?
Crude oil can be purified into several grades of mineral oil, says Athena Hewett, founder of Monastery.
Technical grade mineral oil is the least refined and is used for the lubrication of engines and machinery
. Cosmetic grade is more refined and is used in cosmetics and skin care, hence the name.
What is mineral oil called because of its importance?
Also Known As
Mineral oils are also called base oils, mineral base oils, baby oils, or lubricant base oils.
How does mineral oil work?
Mineral oil is used to
treat constipation
. It is known as a lubricant laxative. It works by keeping water in the stool and intestines. This helps to soften the stool and also makes it easier for stool to pass through the intestines.
What is ppm in transformer oil?
PPM stands for
Parts Per Million
. It is used to measure the weight of moisture divided by the value of oil. The moisture content in oil lowers the insulating system dielectric strength that permits flashover to harm a transformer. For example, for mineral oil, a generally accepted maximum moisture content is 35 ppm.
What is density of transformer oil?
| S.No. Characteristics Value | 2. Density at 29.50C, g/cm3 (Max.) 0.89 | 3. Kinematic viscosity at 27 0 C, cSt, (Max.) 27 | 4. Interfacial tension at 27 0 C , N/m , (Min.) 0.04 | 5. Flash Point , 0 0 C , Pensky Marten(closed ) , (Min) 140 |
|---|
What is the dielectric strength of mineral oil?
| Name Dielectric constant Max. breakdown strength (MV/cm) | Mineral oil 1.0 | n-Hexane 1.1–1.3 | n-Heptane | Castor oil natural ester 4.7 |
|---|
