MICANITE
OR BUILT UP MICA
Laminated
Mica or Mica products are employed in electrical engineering already since
the turn of the century. Micanite is the name given to sheet material
which is made up of fine mica lamellae, called "splittings",
bonded together by a variety of bonding agents such as Shellac, epoxy,
alkyd or silicone, in order to obtain particular characteristics for specific
uses. Variations can be made in the method of manufacture, the types of
Mica, and the type of quantity of bonding material used to form thick
or thin, stiff or flexible products in the form of sheets, webs or ribbons
and also moulded articles.
COMMUTATOR
MICA SHEETS
Commutator
Mica Sheets are made of natural muscovite mica splittings bonded
with a minimum amount of resins in compact, dense and rigid flat
plates by means of multiple high temperature pressing primarily
for use as insulation between copper segments or bars of commutators
used in traction motors as well as other electric motors and turbo-generators.
The resin is cured for several hours at high temperature to preclude
any ozzing or slippage of the mica. The natural cohesive forces
between the mica platelets combined with the bonding strength
of the rigid thermosetting binder makes these plates adequately
resistant to high heat and pressure encountered in the commutators.
These plates have high dielectric strength, high thermal stability,
good voltage endurance and excellent mechanical and electrical
properties. Besides they have extremely low compressibility as
is essential in maintaining the commutator's dimensional stability
under large centrifugal stresses in operation. Their other properties
are smooth surfaces, uniform thickness, great resistance to crushing
and excellent mechinability. Commutator mica sheets bonded with
shellac resins provides an excellent overall properties. Epoxy
and alkyd yield dimensional stability with ability to withstand
extreme compression stress.
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HOT
MOULDING MICA SHEETS
Hot-Moulding
Mica sheets are produced from natural muscovite mica splittings
bonded with a thermoplastic resins either shellac, epoxy or alkyd-vinyl
by applying adequate heat and pressure. The amount of bond content
range from 18% to 22% depending on type of product demanded. The
relatively high amount of bond facilitate the mica to slip relative
to each other during the moulding process as necessary in assuming
the desired contour. These sheets are rigid at room temperature
but soften when heated at temperature between 100oC to 140oC and
could easily be moulded into practically any shape upon the application
of either hot or cold process. With further cure, the sheets form
into rigid well bonded structure retaining the shape of their
moulded forms. Moulding sheets bonded with shellac provides optimum
mouldability having an excellent overall properties and have been
traditionally most popular, while epoxy or alkyd-vinyl bonded
sheets offer toughness and durability under severe mechanical
stress applications.
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HEATER
MICA SHEETS
HEATER
MICA SHEETS are produced from natural muscovite mica splittings
bonded with synthetic, epoxy or silicone resins suitable for thermal
class 'B', 'F', and 'H' into a rigis sheets under high heat, and
pressure conforming to IEC Standards 371.3.3. These sheets are
hard and dense and could readily be punched to any specified shape
and designs providing and excellent overall properties. They have
high dielectric strength, flexural strength, thermal stability,
low moisture absorption and good arc resistance properties. They
are superior product in intensity,waterproof ability, incombustibility
and electrical insulating properties.
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FLEXIBLE
MICA SHEETS
Flexible
Mica Sheets are produced from natural Muscovite mica splittings
bonded with polyester or silicone resins. The controlled low binder
content assures a throughly cured product in which the binder
will not ooze or flow from the mica structure. They possess excellent
flexibility and adhesiveness to permit winding or wrapping of
the sheets at room temperature without heating. They can be formed
or bent readily to any shape and will not become brittle and stiff.
They can be applied to unusual configuration without tear. They
remain flexible at room temperature, rigid at high temperature,
develops increased tenacity and are fully oil resistant. Besides
they do not react with copper. They have high moisture and heat
resistance, high dielectric strength, excellent chemical resistance
and electrical insulating properties. They have long shelf life
and thus eliminates inventory problems normally encountered with
conventional electrical insulating products.
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MICA
MANUFACTURING CO. PVT.LTD.
3C,
Camac Street, P.O.Box
9052,
Calcutta 700 016 INDIA
Tel: +91-33-2229-2277/2229-4505
Fax:+91-33-2229-5216/2474-7959
E-mail
:micamafco@vsnl.net
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