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 ENAMAL 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 :
1. TOLERANT TO COPPER & IRON CONTAMINATION RESULTING IN THE
ELIMINATION OF RED SMUT.
2. LOWER DRAG OUT & TANK SPRAY BECAUSE OF EFFECTIVE SURFACE
ACTIVE AGENTS.
3. LOW SLUDGE FORMATION RESULTING IN THE ECONOMY OF HEATING.
4. SUITABLE TO WIDE RANGE OF IRON ALLOYS,CARBON STEEL,CAST &
MALLEABLE IRON.
5. COATING THICKNESS UP TO 2-3 MICRONS CAN BE OBTAINED.
BATH SOLUTION : MAKE UP :
BLACKODIZING SALT MS 152 – TAKE 900 GM OF SALT PLUS
650 ML WATER TO GET 1 LIT.
SOLUTION.
OPERATING CONDITIONS :
TEMPERATURE – 135-140* C
TIME – 3-20 MINUTES
MAINTENANCE :-
TO GET DESIRED RESULTS THE SOLUTION SHOULD BOIL WITHIN THE OPERATING TEMPERATURE OF 135-140* C. IF THE SOLUTION BOILS, BELOW 138* C. BLACKODIZING SALT MS 152 SALT SHOULD BE ADDED TO INCREASE THE BOILING POINT. FOR EVERY 1* 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 142*C.WATER SHOULD BE ADDED TO MAINTAIN THE BOILING RANGE OF 135-140*C.THE TEMPERATURE OF THE SOLUTION SHOULD NOT BE ALLOWED TO RISE ABOVE 145* 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 MINIMISE 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.