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HAND TOOLS AND APPLIANCES USED FOR FORGING

The tools and appliances used and their applications in numerous forging operations are described below :

The Anvil : 

The anvil forms a support for black smith's work when hammering. The body of the anvil is made of mild steel with a tool steel face welded on the body, but the beak or horn used for bending curves is not steel faced. The round hole in the anvil called pritchel hole is used for bending rods of smaller diameter, and as a die for hot punching operations. The square or hardy hole is used for holding square shanks of various fittings. 

Anvils vary up to about 100 to 150 kg and should stand with the top face about 0.75 m from the floor. This height may be attained by resisting the anvil on a cast iron or wooden base.

The swage block :

This forge shop tool is used for mainly squaring, sizing, heading, bending and forming operations. It is 0.25 m or more wide and may be used either flat or edge wise in its stand.

Hand Hammers :

Two kinds of  hammers are used in hand forging : 

(1) Hand Hammers used by smith himself and 

(2) Sledge Hammer used by striker 

Hand Hammers may be classified as : 

(a) ball peen hammer , 

(b) Straight peen hammer , and 

(c) cross peen hammer.

Hammer heads are made of cast steel, the ends hardened and tempered. The striking face is slightly convex. The weight of a hand hammer varies from about 0.5 to 2 kg while the weight of the sledge hammer varies from 4 to 10kg. 

Tongs : 

The work to be forged is generally held with tongs. The tongs generally used for  holding work.

1. The gad tong used for general pick-up work, either straight or tapered.

2. The straight-lip fluid tong used for square, circular and hexagonal bar stock. 

3. The ring tong used for bolts, rivets, and other work of circular section. 

4. The flat tong used for holding work of rectangular section. 

Chisels : 

Chisels are used for cutting metals and for nicking prior to breaking. They may be hot or cold depending on whether the metal to be cut is hot or cold. The main difference between the two is in the edge. The edge of a cold chisel is hardened and tempered with an angle of about 60* whilst edge of a hot chisel is 30* and the hardening is not necessary. The edge is made slightly rounded for better cutting action.

Swages : 

Swages are used for work which has to be reduced and finished to round, square or hexagonal form. These are made with half grooves of dimensions to suit the work being reduced. Swages consist of two parts -- the top part having a handle and the bottom part having a square shank which fits in the hardy hole in the anvil face.

Fullers :

Fullers are used for necking down a piece of work. They are made in top and bottom tools as in the case of swages. Fullers are made in various shapes and sizes according to needs, the size denoting the width of fuller edge.

Flatters : 

Flatters are used to give smoothness and accuracy to articles which have already been shaped by fullers and swages.

The Set - Hammer : 

It is really a form of flatter. A set hammer is used for finishing corners in shouldered work where the flatter would be in convenient. It is also used for drawing out. 

The punch and the drift : 

A punch is used for making holes in metal part when it is at forging heat, and holes are opened out by driving through a larger tapered punch called a drift.


Forging Tools





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