Does 01 year apprenticeship training will count as a work experience? I know, many student have this doubt that whether apprenticeship training will count as a work experience or not ? and it should be. So let me tell you today and clear your doubt about apprenticeship training count as a work experience . W ell, when I also completed my apprenticeship training, I had also this doubt in my mind. Then I searched and read about it many places and finally I got the proof of apprenticeship training will count as a work experience. My finally answer is YES apprenticeship training will count or consider as a work experien ce. I share with you the proof this. Click Here (Go to http://portal.mhrdnats.gov.in > Help > Process Manual (English) > Page No. 16 > Benefits to students > Point No. 10) Note:- The apprentice which is under the Ministry of Skill Devlopment & Entrepreneurship, in which the All india level exam (AITT) is done after doing the apprenticeship tr
Ingredients of Bricks:-
- Silica: 50-60% silica in good brick earth is desirable. Silica exists in clay either free or in combined form. It prevents shrinkage, warping and cracking of bricks apart from imparting uniform shape to the bricks. However excess of silica destroys the cohesion between the particles of the brick earth and the bricks become brittle.
- Alumina: It is the principal component of the brick earth and a good brick earth must contain about 20-30% alumina. Alumina gives plasticity to the earth thereby making the moulding of brick earth easier. However excess of alumina leads to shrinkage and warping of bricks.
- Lime: About less than 5-8% lime should be present in a good brick earth. It should be in the very finely divided powder form. It prevents shrinkage of bricks. Excess of lime causes bricks to melt thereby losing its shape.
- Iron Oxide: About 3-5% iron oxide is desirable in a god brick earth. Iron oxide gives red color to bricks. Excess of iron oxide leads to dark coloration in bricks like dark blue or blackish color. However less quantity of iron oxide makes the bricks yellowish in color.
- Magnesia: A very small quantity such as 0.01-1% of magnesia gives yellow color to bricks. It also decreases shrinkage.
Manufacturing of brick process:-
These are the process of manufacturing of bricks
Preparation of clay
- Unsoiling: The topmost layer of soil (about 20-30 cm) is taken out and discarded since top clay layer is full of impurities.
- Digging: Clay is then dug out from the ground. This clay is then spread on the ground.
- Cleaning: Clay obtained from the dug hole is cleaned of stones, pebbles, vegetable matter etc. The lumps of clay are crushed to powder from.
- Weathering: The clay is then left in the atmosphere for mellowing. This period of exposure varies from few weeks to full season.
- Blending: After weathering, ingredients are added to clay and blending brings about a homogeneous mixture.
- Tempering: Here water in required quantity is added to clay and the resulting mixture is the kneaded. Tempering is done thoroughly to have a homogeneous mass.
Moulding
Moulding can either be done with hands or with machine. Since bricks shrink during drying and burning and thus moulds are made larger than the size of fully burnt bricks. During moulding, a central depression of about 1 cm - 2 cm is made which acts as a key for mortar joint and also can be used to embross the name of the manufacture.
Drying
Damp bricks when burnt show cracking burnt and their shape gets distorted. Thus bricks are dried before burning. While drying, bricks are so dried that there should be free circulation of air.
Burning
Bricks should neither be under burnt nor over burnt. Under burnt bricks are soft while over burnt bricks are brittle.
Properties of good building bricks:-
- Bricks should not have a crushing strength less than 5.5 N/mm2.
- The bricks should be table moulded and kiln burnt. Moreover they must be free from cracks and must have regular shape with sharp edges.
- The bricks must produce a clear ringing sound when struck with each other.
- These bricks when broken or fractured should show a bright, homogeneous and uniform structure free form voids.
- The bricks should be hard enough so that no impression is left on the surface when scratched with nail or finger.
- When brick immersed in water for 24 hours, the bricks should not absorb water more than 20% by weight of one meter.
- The brick should not break into pieces when dropped on a flat hard ground from height of one meter.
- The brick should have low thermal conductivity and they should be sound proof.
- When brick soaked in water for 24 hours, the bricks should not show patches of white salts when dried in shade.
Classification of bricks:-
Bricks are classified into the following categories.
- 1st class bricks: These are table-moulded, kiln burnt bricks with sharp edges and standard shape. These are burnt in kilns. These are used in superior quality permanent type constructions. The compressive strength of this class brick is 105 kg/sq.cm.
- 2nd class bricks: These are ground-moulded, kiln burnt bricks with slightly irregular shape. These bricks may have hair cracks and their edges are not so harp. These are used where a coat of plaster is to be provided. The compressive strength of this class brick is 70 kg/sq.cm.
- 3rd class bricks: These are ground-moulded, clamp burnt bricks. These are not hard and have rough surfaces with irregular edges. These are used at places where the rainfall is not heavy and for other temporary type of constructions. The compressive strength of this class brick is 35 kg/sq.cm.
- 4th class bricks: These are over-burnt bricks with irregular shape and are dark coloured. These have a compact structure. These are generally used a aggregates for concrete to be used in foundations, roads etc. The compressive strength of this class brick is less than 35 kg/sq.cm.
Test for bricks:-
- Shape, size and color test: In this, 20 bricks are stacked along length-wise, width-wise and height-wise. Measurement is then made to test whether the bricks are of required size. Bricks are also closely examined for their sharp and uniform edges.
- Water absorption: As per IS 3495 (Part-II) : 1992 bricks when immersed in cold water for 24 hours, water absorption by bricks must not exceed 20% by weight up to class 12.5 brick and 15% by weight for higher classes of bricks.
- Compressive strength test: This test is done in a compression testing machine. Bricks are tested for their compressive strength as per IS 3495 (Part-I) : 1992.
- Efflorescence: As per IS 3495 (Part-III) : 1992 bricks shall have a rating of efflorescence as moderate up to class 12.5 bricks and slight' for higher classes of bricks.
- Hardness: Here a scratch is made on the brick surface with a nail or some other hard pointed material. If it does not leave any impression then the brick is of good quality.
- Soundness test: Two bricks when struck together must produce a clear ringing sound.
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