Some important foundry tools and equipments are shovel, riddle, rammer, slick, lifter, swab, bellow, trowel, gate cutter, gaggers, moulding boxes and moulding machines.
1. Hand tools
The following hand tools are commonly employed in preparing the mould in foundry:
(a) Shovel
A shovel consists of a square pan fitted with a wooden handle. It is used for mixing and for moving the sand from one place to another in the foundry.
(b) Riddle
A riddle has a standard wire mesh fixed into a circular or square wooden frame. It is used for cleaning the moulding sand.
(c) Rammer
A hand rammer is made of wood or metal. It is a short rammer and is used for packing and ramming the sand for bench moulding. The floor rammer is similar in construction, but have long handles. It is used for floor moulding or for ramming large moulds. The peen rammer has a wedge-shaped end and is used for setting into corners and pockets of the mould. The pneumatic rammer is an automatic rammer operated by compressed air. It is used in large moulds saving considerable labour and time.
(d) Slick
A slick is a double ended tool having a flat on one end and a spoon on the other. It is used for repairing and finishing the mould surfaces after the pattern is withdrawn.
(e) Lifter
A lifter is made of thin sections of steel of various width and lengths with one end bent at right angles. It is used for smoothing and cleaning out depressions in the mould.
(f) Swab
A simple swab has a small brush having long hemp fibres. A bulb swab has a rubber bulb to hold the water and a soft hair brush at the open end. It is used for moistening the sand around the edge before the pattern is removed.
(g) Bellow
A hand operated bellow is used to blow loose particles of sand from the cavities and surface of the mould.
(h) Trowel
It consists of a metal blade with a wooden handle. The small trowels of various shapes are used for finishing and repairing mould cavities as well as for smoothing over the parting surface of the mould.
(i) Gate cutter
It is a U-shaped piece of thin sheet. It is used for cutting a shallow trough in the mould to act as a passage for the hot metal.
(j) Gaggers
These are iron rods bent at one end or both ends. These are used for reinforcement of sand in the top of the moulding box and to support hanging bodies of sand.
2. Moulding boxes (Flasks)
The sand moulds are prepared ·in a specially constructed boxes called flasks, which are open at the top and bottom. They are made in two parts, held in alignment by dowel pins. The top part is called the cope and the lower part as drag. If the flask is made in three parts, the intermediate part is called a cheek. These flasks can be mad of either wood or metal.
3. Moulding machines
The various types of moulding machines are as follows:
(a) Jolt machine
It is used for ramming of sand in the mould . This machine rams the sand harder at the pattern face with decreasing hardness towards the back of the mould.
(b) Squeezing machine
This machine rams the sand harder at the back of the mould and softer on the pattern face. It is very useful for shallow patterns.
(c) Jolt-squeeze machine
This machine produces uniform hardness of sand in the mould.
(d) Sand slinger
It is used for uniform packing of sand in the mould.
(e) Diaphragm moulding machine
It is used for uniform ramming and hardness of the sand in the flask.
(f) Stripping plate machine
It is used to draw the pattern from the mould.
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