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BLACKODIZING SALT MS-152
Blackodizing Salt
MS-152 produces
adherent, non
flaking and
corrosion resistant
black coating on Iron and steel by
immersion process. Sealing of the black coating is neccessary and can be achieved
by Oiling, Waxing or Lacquering.
Finish
depends upon
the preparation of base metal
and final
oiling, waxing or
lacquering. Bright finish can
be achieved
by polishing the surface to fine degree and by giving a
coat of high bodied
glossy clear baking enamel on untouched black finish.
Non reflective finish
can be obtained by shotblasting, polishing
with greasless composition or etching the basis surface.
Blackodizing Salt MS-152 has
the following advantages :
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1.
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Tolerant
to Copper & Iron contamination resulting
in the elimination of red smut. |
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2.
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Lower
drag out & tank spray because of
effective surface
active agents.
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3.
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Low
sludge formation resulting in the economy of heating.
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4.
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Suitable
to wide range of Iron alloys,
Carbon steel, Cast &
malleable Iron.
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5.
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Coating
thickness up to 2-3 microns can be obtained.
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Bath solution : |
make up : |
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Blackodizing
Salt MS-152 |
Take
900 gm of salt plus
650 ml water to get 1 lit
solution.
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Operating conditions :
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Temperature
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135-140º
C
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Time
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3-20
minutes
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Maintenance
:-
To
get desired
results the
solution should
boil within
the operating temperature
of 135-140* c. If the
solution boils,
below 138º C. Blackodizing
salt ms 152
salt should be added to
increase the boiling
point. For
every 1º C
rise 15 gm/ litre of
salt is required.
Water
evaporates from
the bath and the boiling point
of the
solution slowly
increases. If the boiling point of
the solution
increases more then 142o C. water should be added to
maintain the
boiling range of 135-140o C. The
temperature of
the solution should not be
allowed to
rise above 145o
C. As the
bath constituents
will get
destroyed. Since operating
temperature of the solution is above the
boiling point of water, addition of water should be made
very carefully to avoid spattering and eruption of the solution.
Equipments :-
Steel
or stainless
steel tanks, heaters etc.
are
suitable for
Blackodizing Salt MS-152 process. For addition of water
3/8" water pipe should be fitted just
above the normal
solution level. The end of the pipe should be
capped
And 1/8" holes should be
drilled in the pipe on the side facing the tank
wall. Also
the end of the pipe should be
covered with
a splash guard
to minimize the spread of solution spray when the cold
water comes in contact with solution.
Preparation
of solution :-
Clean
the tank
free of grease, rust and scale. Fill half
of its
capacity with clean cold water. Slowly add the salt by
stirring. Dissolve the salt and make up the level with
required quantity of
water. Heat the
solution to the required temperature and use
the bath.
Sequence of
operation :-
1. Surface
preparation
2. Degrease
3. Rinse
4. Pickle
in acid or alkaline solution.
5. Rinse
6. Dipin
Blackodizing Salt MS-152.
7. Rinse.
8. 0.5%
hot chromic acid dip
9. Dry.
10. Oil
wax lacquer.
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