Smithy shop (Forging) Introduction

Also Read

Introduction

• A smithy’s work involves heating of a metal stock to a desired temperature, enable it to obtain sufficient plasticity, followed by the operations like hammering, bending, pressing etc., to give it the desired shape. This is known as forging.
• The above operations can either be carried out by hand hammering, by power hammers, or by forging machines.
• Hand forging is the term used for the process when it is done by hand tools. Similarly, forging done with the help of power hammers is known as power forging, when carried out by means of drop hammers as drop forging, and when by forging machines as machine forging.
• Applying pressure for shaping the metal, the primary requirement always is to heat the metal to a definite temperature to bring in into the plastic state.
• This may be done either in an open hearth, known as smith’s forge, or in closed furnace. Small jobs are normally heated in the Smith’s forge and larger jobs in closed furnaces.
• The Hand forging process is employed for relatively small components, machine forging for medium sized and large articles requiring very heavy blows and drop forging for mass production of identical parts.

Smith’s forge or hearth:

• It has a robust cast iron or steel structure consisting of 4 leg supports, an iron bottom known as hearth, a hood at the top and tuyere opening into the hearth either from the rear or from the bottom.
• The hearth carries the coal and provided with fire bricks lining to withstand the extensive heat produced due to the combustion of coal. In the absence of this lining the heat produced, as started above, will directly effect the metal structure of the hearth, so that the body, particularly the bottom and the surrounding walls, may even melt.
• With the result, the entire structure will collapse and the hearth will no more be useful.
• Air, under pressure is supplied by the blower, suitably placed somewhere near the forge, through the tuyere opening in the hearth.
• This blower can either be hand operated or power driven. The latter is preferable, but in the absence of availability of power supply choice of the former has no alternative.
• If hand blowers are to be used, they are usually mounted at the rear of the forge itself. In case the power driven units are to be employed the blower is suitably placed in one corner of the shop and all the forges are connected with it by means of a well-laid pipe running underground all around the hearths.
• At suitable points auxiliary pipes are used to connect the tuyere with the main pipe line.
• A valve is incorporated in the auxiliary pipe, just before the place where it is connected with the tuyere, to control the supply of air to the furnace.
• The chimney provided at the top enables as easy escape of smoke and gases produced due to the burning of coal.
• A water tank is provided, in front of the forge, which carries water for the purpose of quenching.
• These hearths can also be made to have masonry construction provided with all the attachments like chimney, tuyere, blower, water tank, etc.

Smithy shop tools