The manufacturing process of Piston
Rings has changed considerably since
the inception of internal combustion
motor. Modern piston ring is automated
with little or no human intervention.
This is not the case with BAR International.
Our
strength lies in our ability to
manufacture very low number of piston
rings with quality & reliability
, but mass production is undertaken
for large buyers. We use many modern
manufacturing processes but also
older in methodologies which ensures
us as a niche manufacturer of quality
product having ISO-9002 certification.
SUBJECTS
FOUNDRY
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The
foundry is the starting
point for piston rings
in Grey Iron, SG Iron
/ Ductile Iron and so
on. A Induction furnace
is used to heat pig iron,
along with chemicals to
operating temperature,
for about one hour. The
process allows the die
to readily accept the
material when it is poured,
so as to get perfect micro
structure and composition
of castings. |
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THE
MATERIAL
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Here,
utmost attention is paid
to the raw material used
in manufacturing. High-grade
pig iron is used with
an inoculation of alloy
chemicals. An eye is kept
on the dies used in manufacturing.
These are usually made
of cast iron. |
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THE
DIE
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The
dies used are made of cast
iron. |
THE
PROCESS
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The
process starts with heating
the material to high temperatures
of 1500 - 1800 degrees
Centigrade, depending
on the type of castings.
The material is scooped
up with a ladle from the
pot and then poured into
stacks of pillars, created
from special sand prepared
from moulding, as created
from die. This is allowed
to cool in air or in an
oven overnight, depending
on type of casting. Thereafter,
runners & risers are
removed to make individual
casted rings, machinable.
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MACHINING
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The
ring casting is treated
from both sides after
deburring on OD. The
rings are grinded to
a specific accuracy
on axial width and sorted
out for blowholes. Thereafter,
they are turned for
OD and ID on lathes.
The free gap is created
with / without heat
treatment. Following
which, gap sizing, chamfering,
OD, grooving, slotting,
I.D. grooving scrapper,
bevelling, keystone
making or one side tapering
is done, in accordance
with the drawing or
samples as per the specifications
on compression rings,
oil control rings. |
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CHROME
PLATING
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Hard
chrome plating is done for
many hours, depending upon
the plating thickness specified.
The focus is on delievering
a good job the first time
, every time. This drastically
improves wear resistance and
provides low friction and
good thermal conductivity.
It also gives extremely high
hardness ( Vickers hardness-800
to 1000 ) and a high melting
point. |
HONING
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The
plating on OD is honed
for super finish and 100%
light tight rings. This
is to ensure world class
product finishing and
consequently, more satishfaction
by the end user. |
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LAPPING
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This
is the fine process for
final control of axial
width with closest tolerances
of 5 to 10 microns. |
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PHOSPHATING
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The
chemical phosphating is done
if required by buyer as rust
preventive If to be sent without
phosphating, then high grade
rust preventive oil coating
is done |
INSPECTION
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All
parameters of the piston
ring are checked at each
machine ensuring in process
control but still finally
100% rings are checked
after completion to double
ensure the perfect quality
of each piece of ring
sold by us. The markings
of the top and other markings
are done as needed with
oversize and sent for
Despatch |
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DESPATCH
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The
piston rings are finally packed
in required packing of the
buyers and Despatched by sea
or Air to the customer. (Sea
worthy packing containers
if sent by sea.) |
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