Foundry Shop and tools

Foundry Shop and tools

The place where jobs are prepared by melting and pouring the molten metal into moulds is known asfoundry. 

A mould is a cavity so prepared that it can be used to make castings by molten metal into it. 

Pattern is a model of anything which is used to prepare moulds by placing it in sand. 

The molten metal poured into mould, on cooling is known as castings. 

The capacity of a metal to get forge is called forgability.

TOOLS USED IN FOUNDRY SHOP

Shovel: 

It consists of iron pan with a wooden handle. It can be used for mixing and conditioning the sand and then transferring the mixture in some container.

Trowels: 

These are used for finishing flat surfaces and corners inside a mould. They are made of iron with a wooden handle.

Lifter: 

A lifter is a finishing tool used for repairing the mould and finishing the mould sand. Lifter is also used for removing loose sand from moulds.

Hand riddle: 

It is used for ridding of sand to remove foreign materials from it. It consists of a wooden frame fitted with a screen of standard wire mesh at the bottom.

Strike off bar: 

It is a flat bar, made of wooden or iron to strike off the excess sand from the top of a box after ramming. It’s one edge made bevelled and the surface perfectly smooth and plane.

Vent wire: 

It is a thin steel rod or wire carrying a pointed edge at one end and a wooden handle or a bent loop at the other. After ramming and striking off the excess sand it is used to make small holes called vents in the sand mould to allow the exit of gases and steam during casting.

Draw spike: 

It is a tapered steel rod having a loop or ring at its one end and a sharp point at the other. It is used to tap and draw patterns from the mould.

Rammers: 

Rammers are used for striking the sand mass in the moulding box to pack it closely around one pattern. Peen rammer it consists of a metallic rod with a projection in the front, it is used in packing the sand at the corners of the boxes. Floor rammer it consists of a long steel bar with a peen in the front portion. It is heavier in weight and used in floor moulding for ramming and in very large moulds. Hand rammer, one end is called peen and the other end is called butt. It is used in bench moulding. 

Slicks: 

They are used for repairing and finishing the mould surfaces and the edges after the pattern has been withdraw. The commonly used slicks are heart and leaf, square and heart, spoon and bead and heart and spoon. The above nomenclature of slicks is largely due to their shapes.

Smoothers and corner slicks: 

They are also finishing tools used for repairing and finishing flat and round surfaces, round or square corners and edges. These tools find a special favor in dry sand and loam sand work.

Mallet: 

It is similar wooden mallet as that used in the carpentry work. In foundry work it is used for driving the draw spike into the pattern and then rapping it.

Swab: 

It is a hemp fibre brush used for moisturizing the edges of sand mould, which are in contact with the pattern surface, before withdrawing the pattern. It is also used for coating the liquid blacking on the mould faces in dry sand moulds.

Spruce pin: 

It is a tapered rod of wood or iron which is embedded in the sand and later withdrawn to produce a hole, called runner through which the molten metal is poured into the mould.

Spruce cutter:

 

It is also used for the same purpose as that of spruce pin, but there is a marked difference between their use in that the cutter is used to produce the hole after ramming the mould. It is in the form of a tapered hollow tube which is inserted in the sand to produce a hole.

Clamps, cotters and wedges: 

They are made of steel and are used for clamping the moulding boxes firmly together during pouring.

Nails and wire pieces: 

They are used to reinforce their projections of the sand in the mould or cores made in two halves.

Bellow: 

It is used to blow the loose or unwanted sand from the surface and the cavity of the mould.

Draw screws and rapping plate: 

It is a long mild steel rod with a ring in one end and threaded at the other, there is a plate known as rapping plate consisting of several tapered holes.

Pyrometer: 

It is a device which is used to measure the temperature of molten metal from the burner.

Moulding boxes or flasks: 

The moulding boxes or flasks used on sand moulding are of two types:
a. CLOSED MOULDING BOXES
b. OPEN TYPE OF SNAP FLASKS

These boxes are used in sand moulding may be made of wood, cast iron or steel. They consist two or more parts. The lower part is called drag and the upper part is called cope and all the intermediate parts (if used) is called cheeks. All the parts are individually equipped with suitable means for clamping during pouring.

Wooden flasks are generally used in green sand moulding. Dry sand moulds always requires metallic boxes because they are heated for drying. Large and heavy boxes are made from cast iron or steel and carry handles and grips as they are manipulated by cranes or hoists etc. The closed metallic flasks may have a rectangular or round shape.

A snap flask is hinged in one corner and it is rectangular in shape and it is made of wood. It is used for bench moulding and number of moulds can be made from same set of flask.

Ladles: 

They are used to receive molten metal from the melting furnace and pour the same into the mould. Their size is designated by their metal holding capacity. Small hand shank ladles, used by a single moulder, are provided with only one handle and are made in different capacities upto a maximum 20Kg.

Medium and large size ladles are provided with handles on both sides to be handles by two moulders. They are also made in different sizes with their capacity varying from 30-150Kg. 

Extremely, large sizes with capacities ranging from 250-1000Kg are found in crane ladles can hold even more than 1000Kg of molten metal. They facilitate a better pouring control than the ungeared ladles and ensure more safety for workers.

All the ladles, irrespective of their sizes, consist of an outer casing made of steel or plate bent in proper shape and then welded. Inside this casing is provided a refractory lining. At its top the casing is shaped to have a controlled and well directed flow of molten metal.

Crucibles: 

They are made refractory material and are similar in shape to the ladles. They are used as metal melting pots. The raw material or charge is broken into small pieces and placed in them. They are then placed in crucible or pit furnaces which are coke fired. 

In oil fired tilting furnaces they form an integral part of the furnace itself and the charge is put into them while they are in position. After melting of metal, the crucibles placed in coke-fired furnaces are taken out and received in handles. Pouring is generally done directly by them instead of transferring the molten metal to ladles. But in the case of an oil fired furnaces the molten metal is first received in a ladle and then poured into the mould.