Which Insulation Materials Are Used In Transformers? Miracle Electronics

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Which Insulation Materials Are Used In
Transformers? Miracle Electronics
Insulation is one of the most important qualities
that a transformer has, which is responsible for
providing better performance when the transformer
is operated. In fact, the durability and
stability of a transformer highly depend upon the
proper utilization of the insulation materials
present within it. This means that other than
metallic components like silicon steel and
copper, there are also other important
insulating materials used in power transformers
for better functioning. You must get in touch
with a reliable transformer manufacturer in India
like Miracle Electronics so that you can rest
assured that the transformers you buy will be of
top- class quality with the best materials, both
metallic and insulating, installed within. Now,
let us take a look at the list of insulating
materials present in a transformer, along with
their uses and applications.
Insulating oil Insulating oil is one of the most
important components within a transformer that
acts as both an electrical insulator and coolant
to dissipate heat losses. This oil is seen in
11kV or higher voltage transformers, placed in
the tank where the transformer core is placed. It
is not required
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• in low voltage transformers as the heat
  dissipation in such transformers is very low.
  Insulating oil is obtained by fractional
  distillation and subsequent treatment of crude
  petroleum.
• Insulating paper
• Insulating paper is made up of vegetable fibers
  that are felted together to form a sheet. The
  fibers are obtained from plants like cotton,
  straw, hemp, manila, and coniferous trees. When
  this insulating paper is put into the insulating
  oil under vacuum, it attains extremely high
  electric strength.
• Insulating tape
• As the name itself says, insulating tape is used
  for various taping purposes. These are available
  in a variety of forms like cotton tapes, woven
  tapes, glass woven tapes, and phenol laminated
  paper base sheet. These tapes are used in areas
  where high strength is required. They are also
  used for banding of transformer cores.
• Pressboard
• Used in the electrical, mechanical, and thermal
  designing of transformers, the pressboard is
  also made up of vegetable fibers that contain
  huge amounts of cellulose. These pressboards can
  be moulded into any shape to be used in
  transformers the most commonly seen shapes being
  angle rings and caps.
• Wood-based laminates
• Wood-based laminates are made from selected
  veneers that are obtained from various timbers.
  The veneers are first dried, and then are
  partially/completely saturated naturally. Such
  laminates are used in areas that require higher
  mechanical and lower electric strength. They are
  used in making a variety of components like coil
  clamping rings, cores, yokes, and supports.
• All these insulation materials used in
  transformers are based on their temperature
  withstanding capacity. They are classified into
  classes A, B, C, E, F, H, and Y. Let us
  understand all these classes in detail.

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• Class C materials are those whose maximum hot
  spot temperature is 180C. These include glass,
  mica, asbestos, porcelain, and quartz with or
  without an inorganic binder.
• Class E materials are those whose maximum hot
  spot temperature is 120C. These include wire
  and enamel.
• Class F materials are those whose maximum hot
  spot temperature is 155C. These include glass,
  mica, and asbestos with suitable binding
  impregnation or coating substances.
• Class H materials are those whose maximum hot
  spot temperature is 180C. These are a
  combination of materials like glass fiber,
  asbestos, and mica suitable bonded together.
• Class Y materials are those whose maximum hot
  spot temperature is 90C. These include cotton,
  silk, paper, and wood without impregnation.
• For more details, please visit Miracle
  Electronics