Hybridoma Technology ( Production , Purification , and Application )
Brick
1.
2.
3. BRICKS ARE OBTAINED BY MOULDING CLAY IN
RECTANGULAR BLOCKSOF UNIFORM SIZE AND THEN BY
DRYING AND BURNING THESE.
THEY CAN BE PROPERLY ARRANGEDAND FURTHER,
AS THEY ARE LIGHT IN WEIGHT, NO LIFTING APPLIANCE IS
REQUIRED FOR THEM ,. THUS AT PLACES WHERE STONES
ARE NOT EASIL AVAILABLE, BUT IF THERE IS PLENTY OF
CLAY, BRICKS REPLACE STONE
5. IN THE PROCESS OF MANUFACTURING
BRICKS,THE FOLLOWING FOUR DISTINCT
OPERATIONS ARE INVOLVED
1.PREPERATION OF CLAY
2.MOULDING
3.DRYING
4.BURNING
FOR MANUFACTURING GOOD BRICKS
ON A LARGE SCALE,TEMPERING IS
USUALLY DONE IN A PUG MILL. A
TYPICAL PUG MILL CAPABLE OF
TEMPERING SUFFICIENT E FOR A DAILY
OUT PUT OF ABOUT 15000 TO 20000
BRICKS.PROCESS OF GRINDING CLAY
WITH WATER AND MAKING IT PLASTIC
KNOWN AS PUGGING
6. HOFFMAN’S KILN
THIS KILN IS CONSTRUCTED
OVER GROUND AND HENCE
IT IS SOMETIME KNOWN AS
FLAME KILN.IT’S SHAPE IS
CIRCULAR IN PLAN AND IT
IS DIVIDED INTO A NOMBER COMPARTMENTS OR CHAMBERS .
ROOF IS PROVIDED ,THEKILN CAN EVEN FUNCTION DURING
RAINY SEASON.EACH CHAMBER IS PROVIDEDWITH THE
FOLLOWING:
1. CHAMBER 1 - LOADING
2. CHAMBER 2 TO 5 - DRYING AND PREHEATING
3. CHAMBER 6 TO 7 - BURNING
4. CHAMBER 8 TO 11 - COOLING
5. CHAMBER 12 - UNLOADING
7. BULL’S TRENCH KILN
THIS KILN MAY BE OF RECT-
ANGULAR,CIRCULAR OR OV-
EL SHAPE.IT IS CONSTRUCTED IN
A TRENCH EXCAVATED IN GROUND
BRICKS ARE RRANGED IN SECTIONS.THEY ARE ARRANGED
IN SUCH WAY THAT FLUES ARE FORMED.FUEL IS PLACED IN
FLUES AND IT IS IGNITED THROUGH FLUE HOLES AFTER
COVERING TOP SURFACE WITH EARTH AND ASHES TO PREVENT
THE ESCAPE OF HEA. EACH SECTIONS REQUIRES ABOUT
ONEDAY TO BURN. WHEN A SECTION IS BURNTFLUS HOLES ARE
CLOSED AND IT IS ALLOWED TO COOL DOWN GRADUALLY.
FIRE IS ADVANCED TO NEXT SECTION AND CHIMMNEYS ARE
MOVED FORWARD AS SHOWN BY ARROWS .
8. CLASSIFICATIONS OF BRICK
1. FIRST CLASS BRICK:
THESE BRICKS ARE TABLE MOULDE AND OF
STANDARD SHAPE. THE SURFACE AND EDGES
OF BRICKS ARE SHARP,SQUAR,SMOOTH AND
STRAIGHT.THESE BRICKS ARE USED FOR SUPE-
RIOR WORK OF PERMANENT NATURE.
9. 2. SECOND CLASS BRICK
THESE BRICKS ARE GROUND-MOULDED AND THEY ARE
BURNT IN KILN.THE SURFACE OF THESE BRICKS ARE SOM-
EWHAT ROUGH AND SHAPE IS ALSO SLIGHTLYIRREGULAR
10. 3. THIRD CLASS BRICK
THESE BRICKS ARE GROUND MOULDED AND THEY ARE
BURNT IN CLAMPS.THESE BRICKS ARE NOT HARD AND
THEY HAVE ROUGH SURFACE WITH IRREGULAR AND
DISORTED EDGE
11. 4. FOURTH CLASS BRICK
THESE ARE OVERBURNT BRICKS WITH IRREGULAR SHAPE
AND DARK COLOR.THESE BRICKS ARE USED AGGREGATE
FOR CONCRETE IN FOUNDATIONS,FLOORS,ROADS,etc
12. TEST FOR BRICKS
1. ABSORPTION
2. CRUSHING STRENGTH
3. HARDNESS
4. PRESENCE OF SOLUBLE SALTS
5. SHAPE AND SIZE
6. SOUNDNESS
7. STRUCTURE
13. SHAPE AND SIZE
IN THIS TEST , A BRICK IS CLOSELY INSPECTED . IT SHOULD
BE OF STANDARD SIZE AND ITS SHAPE SHOULD BE TRULY
RECTANGULAR WITH SHARP RDGES. THE BRICK STANDARD
SIZE IS 19*9*9 CM.
SOUNDNESS
IN THIS TEST , TWO BRICKS ARE TAKEN AND THEY ARE
STRUCK EACH OTHER . BRICK SHOULDN’T BREAK AND
A CLEAR RINGING SOUND SHOULD BE PRODUCED.
14. ABSORPTION
A BRICK IS TAKEN AND IT IS WEIGHED DRY . IT IS THEN IM-
MERSED IN WATER FOR A PERIOD OF 16 HOURES . IT IS
WEIGHED AGAIN AND DIFFERENCE IN WEIGHT INDICATES
THE AMOUNT OF WATER ABSORBED BY THE BRICK . IT
SHOULD NOT ,IN ANY CASE ,EXCEED 20 PER CENT OF
WEIGHT OF DRY BRICK.
15. CRUSHING STRENGTH
CRUSHING STRENGTH OF A BRICK IS FOUND OUT BY PLAC-
ING IT IN A COMPRESSION TESTING MACHINE . IT IS PRESSED
TILL IT BREAKS. MINIMUM CRUSHING STRENGTH OF BRICK
IS 35 kg/cm² AND FOR SUPERIOR BRICKS,IT MAY VARY
FROM 70 TO 140 kg/cm² .
16. HARDNESS
IN THIS TEST , SCRACH IS MADE ON BRICK SURFACE WITH
THE HELP OF A FINGER NAIL. IF NO IMPRESSION IS LEFT
ON THE SURFACE BRICK IS TREATED TO BE SUFFICIENTLY
HARD.
PRESENCE OF SOLUBLE SALT
SOLUBLE SALTS, IF PRESENT IN BRICKS , WILL CAUSE EFF-
LORESCENCE ON THE SURFACE OF BRICKS . FOR FINDING
OUT THE PRESENCE OF SOLUBLE SALTS IN BRICK , IT IS
IMMERSED WATER FOR 24 HOURES. IT IS THEN TAKEN OUT
AND ALLOWED TO DRY IN SHADE. ABSENCE OF OF GRAY
OR WHITE DEPOSIT ON ITS SURFACE INDICATES ABSENCE
OF SOLUBLE SALT
17. STRUCTURE
A BRICK IS BROKEN AND ITS IS EXAMINED . IT SHOULD BE
HOMOGENEOUS , COMPACT AND FREE FROM ANY DEFETCS
SUCH AS HOLES , LUMPS , etc
