Forge forge: design features. Making a forge for forging and melting metal Do-it-yourself forging furnace

The forge is an indispensable attribute of workshops engaged in the production of various products using the method of manual artistic forging. Only a certain number of forged elements can be made by plastic deformation of metals at room temperatures. In most cases, they need to be heated. For steel, in particular, the range of optimal forging temperatures is (depending on the steel grade) from 800 ... 900 0 С to 1100 ... 1200 0 С. The forge is the simplest type of heating device that is quite suitable for these purposes.

Invented by the ancient Khalibs for forging copper knives and scrapers (Near East, VI millennium BC), the first forge was made in the form of a primitive depression in the ground with dimensions of about 700 mm. The pit was surrounded by a stone wall, in which an opening was provided for blowing air. The injection of air (which is necessary for the sustainable combustion of fuel) was carried out using bellows. They were a cavity made of goat skins, where air was blown in by levers through an air valve. The return stroke of the lever was provided by a stone, which was installed on the top plate of the bellows, and the valve was operated due to the difference in pressures of cold and hot air.

Existing designs of forge forges are determined by the following factors:

fuel on which the device operates: coke, fuel oil, coal or gas.
by design fuel burning device.
Wanted dimensions workspace.
Appointment, since, in addition to heating for forging, forges are also used for some operations of heat treatment of finished forgings - carburizing, tempering and even hardening.

For safety reasons, forges are more likely to run on coal.

Coke is expensive, fuel oil is characterized by unsatisfactory environmental operating conditions, and gas furnaces require especially careful routine maintenance. However, gas furnaces are characterized by higher efficiency, and also allow quite convenient mechanization of some heating control processes - in particular, gas ignition in the burner or burners.

Common disadvantages blacksmith forges are considered:

Uneven heating metal placed on the surface;
impossibility practical temperature control heated workpiece;
Unwanted saturation surface layers heated metal with sulfur compounds, resulting in increased brittleness of the workpiece.

However, an experienced blacksmith is able to estimate the temperature of the metal by the color of its surface, and the problem of sulfurization is solved by using a better type of fuel.

Fuel consumption during the operation of forge furnaces is 40 ... 150% of the mass of the heated metal, with its surface waste 4 ... 7% (depending on the duration of heating). Modern forges - mostly closed type, because in the opposite case, the efficiency of the heating device drops to 5 ... 10%.

Forges working on coal

The design of the heating device of this type includes:

Code and side walls , which are laid out from refractory bricks (chamotte or dinas).
forge nest, formed by the upper surface of the arch, where the workpieces are heated.
Umbrella, supplied with folding curtains, and designed to improve natural traction in the workspace.
Back wall (firewall), which provides openings for supply of initial air.
air faucet, designed to turn on the air supply to the mountain nest.
protective box made of heat-resistant steel, which connects the inlet cavity at the air supply valve with the furnace nest.
Quenching tank(it can be steel or brick), designed to cool blanks during their heat treatment or to cool the hearth nest itself from overheating and the subsequent formation of temperature cracks.
Chimney, through which the products of combustion of fuel are removed.
Coal storage tanks and various blacksmith tools.

Schematic diagram of the work of the forge

A solid fuel forge is a rather capricious heating device, and its heating requires a certain amount of energy from the blacksmith. practical experience. It is especially difficult to light a forge that has not been used for a long time, and also if the external temperatures and air pressure are low enough. Coal, which is used in such forges, must correspond requirements of GOST 8180.

Preparing the forge for metal heating produced in the following sequence:

From their mountain nest the slags are removed, residuals forged metal, ash and scale (this should be done even when the surface has been thoroughly cleaned after completion of work);
Chimneys and air supply ducts are blown with compressed air(for small forges, you can use a vacuum cleaner);
A small layer of coal is poured onto the surface of the mountain nest, while the opening of the protective box should not completely overlap;
Top on coal put a rag dipped in flammable liquid or sawdust;
After ignition when combustion becomes stable, add the next portion of coal(the fraction may have an increased size compared to the original);
Air valve opens, and is installed in the middle position;
As it burns out, the intensity of the blast gradually increases.

The required quality of heating the workpiece for forging in an open hearth is ensured surface crust formation, which is formed during the combustion of fuel.

Inside the crust - always more heat, so the workpiece is placed inside, and the top is covered with another dose of coal. At the same time, they try not to destroy the upper surface of the crust, since otherwise the heating will be slower, and metal waste and scale formation will increase. Sometimes, to weaken the processes of carburization of the metal, the crust is sprayed with water.

IN open forges the least intense heating of the metal occurs at the periphery of the hearth nest, therefore fresh coal is poured precisely along the perimeter of the heated workpiece. If the crust layer becomes too thick (more than 5 ... 10 mm), it is broken, because. in this case, the thermal conductivity to the workpiece decreases.

The workpiece during heating periodically turn to ensure that all its parts have the same heating conditions. The flame when burning coal should have a uniform color with a minimum of soot.

hot steel colors at various temperatures are:

Dark cherry colors - 700 ... 750 0 C;
Cherry red - 750 ... 800 0 C;
Red - 800 ... 850 0 С;
Light red - 850 ... 900 0 С;
Orange - 900 ... 1050 0 С;
Dark yellow - 1050 ... 1150 0 С;
Light yellow - 1150 ... 1250 0 С.

Overheating of the metal above the specified temperatures is unacceptable. Overheated metal is characterized by a coarse-grained structure, which is less susceptible to forging, especially when forming complex forged elements.

Forges powered by gas

Gas forges are brought to the design mode much easier, and this is their advantage over solid fuel heating devices. Typical design such a mountain next:

Camera, made of refractory material, and outside lined with thick heat-resistant steel.
front damper, opening with hinges or a counterweight, and equipped with a viewing window.
Under made of heat-resistant fireclay bricks.
Burner. The type of burner is determined by the calorific value of the gas used. For example, for a propane-butane mixture, diffusion combustion burners are effective, in which the mixing of air and gas occurs only after the gas and air leave the device, and the mixing of the components occurs due to diffusion processes. Such burners provide the most uniform heating of workpieces (especially long ones), and the minimum waste of metal is achieved due to the fact that there is always a protective layer above its surface.
mixing gearbox, providing mixing of air and gas (included in the structure of a cylinder with liquefied gas).
Nozzle, the configuration of which is determined by the shape of the billets heated in the hearth.
Grate, designed to improve traction and collect scale.
Fan, which ensures the injection of air in the required volume with its subsequent supply to the burner operating area.

For the operation of such furnaces, a stationary source of electricity is required. It is expedient to use gas forges for heating parts of long billets for forging: heating is much faster and, consequently, scale formation is less.

When using a gas forge, the following safety requirements must be strictly observed:

Thoroughly ventilate the forge room. Avoiding stagnant zones where combustible gas can accumulate;
Do not use oxygen and oxygen-containing mixtures near the operating device that are prone to spontaneous combustion and self-ignition;
Provide for complete afterburning of gas in the working space of the hearth (determined by a gas analyzer, which is mandatory during a test run of a gas hearth);
Thoroughly clean the grate after turning off the gas supply to the device.

In order to reduce scale formation, for heating billets for forging, they are also used and resistance heaters, But similar devices"horns" can be called a stretch.

The word "bugle" comes from the German horn. In fact, it is a "horn". They made an ancient forge with their own hands to obtain bloom iron. His appearance resembles an inverted trumpet made of horn, which served as the basis for calling it a horn. From him came the blacksmith's forge.

Note: In the forge, the device is used as a tool for heating the metal before it is processed. Therefore, blacksmith forges are items that are needed by everyone who deals with metal. With it, you can achieve high temperatures - over 1000 degrees. Therefore, he can allow himself to manufacture various metal structures. In our case, these can be boilers, pipes, decorative elements of fireplaces and other metal products.

There are two main types of equipment:

stationary;
desktop.

An important feature that blacksmith forges have is that they can be made by hand. Of course, if you build a unit that runs on natural gas, you will not be able to get a serious product, like a Damascus blade, but you can make a structure in just a few minutes. This will require some refractory bricks and steel pieces. Such a device will be enough for melting or forging.

Homemade portable desktop blacksmith forge

Compound

Consider the arrangement of traditional forge equipment:

refractory table;
hearth;
lattice;
air drainage and chamber;
umbrella;
valve;
duct;
hardening bath;
removable crucible;
window for long products;
chimney.

Operating principle

Let's figure out how to make a bugle with your own hands. After all, the traditional design for home use can be simplified without compromising the quality of the process.

The basis of functioning chemical reaction combustion of carbon, which is effectively used to work with metal. It combines with oxygen, and the metal is released in free form. The forge also uses the calorific value of carbon. By adding air to the fuel, combustion will be much faster given enough carbon. As a result, the temperature will increase, more heat will be received.

The flame of the blacksmith's forge, made by hand

The air supply to the forges is organized in such a way as to provide a slight lack of oxygen in order to prevent oxidation of the metal. If the workpiece is in the device for longer than the recommended period, the properties of the metal will be violated. For example, steel sheets can become brittle with increased hardness. This means that its properties will be closer to those of cast iron.

Fuel

Note: A conventional blacksmith's forge runs on coal. However, wood can also be used. To do this, they warm up to coals. You can simplify the device if you use, for example, butane or propane.

Their composition includes hydrogen and carbon, which, when combined with oxygen, release a lot of heat. Moreover, such mixing can occur beforehand, for example, in the burner.

However, it must be understood that it will be almost impossible to manage natural gas for such purposes, since it consists of different hydrocarbons that require different amounts of oxygen. Therefore, it will not be possible to organize an optimal air supply. In addition, natural gas contains sulfur, which adversely affects the properties of the metal. Therefore, the mixture requires pre-cleaning or can be used to process non-critical parts.

Kinds

Let's consider what blacksmith forges can be. They are the main tool of the forge. Thanks to the development and improvement, many varieties have appeared:

electric or fuel;

Portable electric blacksmith forge blue

on liquid, gaseous or solid fuel;

Blacksmith's forge on coals in action

closed or open type;

with central lance or side nozzle;

Homemade blacksmith forge of simple design with a side nozzle

Open forge with central lance in action

stationary or portable.

Stationary forge in action

Consider the most popular types.

Gas

Making such a forge with your own hands is quite difficult, but possible. The homemade version, like the purchased one, traditionally has a camera and furs. Operates on propane-butane. Gas is supplied to the mixing reducer, after which it enters the gas burner. The latter in some cases may be located on the side. This format is often used in homemade options used in forges.

You can make a gas horn yourself to warm up the ends of small-sized products. It can be used to create decorative solutions in artistic forging.

Portable

These forges are easy to use. The design uses a steel frame, on top of which there is a recess from. At its bottom there is a lance, with the help of which the air supply is organized (using a compressor or a fan). The tuyere has small slots through which air is forced in, but coal or slag is not passed through.

Portable gas models blacksmith forges

Such a forge is used for processing small products. It can be carried or transported, so the place of work may be ad hoc.

Stationary

They can be open or closed type.

Device open version execution - a frame with a table in the form of a trough about 70 cm high. The hearth is lined with fireclay bricks, inside it there is a lance. For cooling the device, a water tank is provided, located in front. The fan creates pressure to supply air through the channel.

Stationary desktop forge in action

The lever allows you to adjust the volume, which makes it possible to change the temperature in the hearth. The shutter protects the tuyere from falling into it pieces of ash and coal. Flue gases are removed through an umbrella and exhaust pipe. The fuel can be charcoal or coke.

The closed device has the following advantages:

quickly reaching the maximum temperature;
high efficiency;
increased fire safety.

The only problem if you make such a forge with your own hands is that it is difficult to work with large or long products, especially if you need to warm up their middle part.

The chamber is made of fireclay bricks, located in metal frame. It has a lance, a grate, a window and a furnace hatch.

Create a stationary device

Consider how to make a bugle with your own hands of a simple design. To do this, you need six refractory bricks. Of course, a very high temperature cannot be obtained under such conditions, but it is quite possible to heat the metal, say, for forging or bending.

For the manufacture of grates, you can take steel strips with a thickness of about 5 mm. Shelves can be made from pipe scraps. Charcoal or coke can be used as fuel. A blowtorch is used for ignition. However, when exposed to heat from a forge, it may not withstand, so an asbestos partition must be placed between them. You can also use a burner (petrol or gas). Since there is no umbrella with a chimney, a homemade device is used on outdoors.

Simple DIY outdoor blacksmith mount

Create a portable device

For greater versatility, you can do it yourself and a portable version. It can be built from a goose. Pressurization can be made homemade using a fan from a manual siren, a corrugated pipe.

Self-creation of a blacksmith's forge

Of course, such homemade design has more features than the described stationary version, but there are also disadvantages:

the temperature is not very high - up to 900 degrees;
expensive operation, given the cost of carbon;
because in such homemade device there is no space for burning out, it functions on charcoal or coke.

Blacksmith's forge made from pipe

Summary

Forges are a fairly common sight today, despite the consumer attitude towards things that are easier to buy than to make. However, if you are not too lazy, make a device with your own hands, build a small forge, you can create original products from metal, which can be used to decorate private properties, create devices for providing space heating, etc. Therefore, making a forge forge with your own hands is the right decision.

DIY Forge Tips

“Horn” is a word of German origin horn, originally “horn”, then horn received many other meanings, if only the object somehow looked like a horn or came from it; one of the highest peaks of the Alps is called the Matterhorn. The ancient smelting furnace, in which flash iron was obtained, looks like a signal pipe from a horn, placed with a bell down, so it became a furnace, and from it a forge, although it no longer looks like a horn.

In the forge, the forge is used to heat the metal before forging, cementing and other heat treatment operations. The horn is a very necessary thing for everyone who works with metal: it allows you to get in artisanal conditions temperatures up to 1100 and even 1200 degrees, can be both large stationary and small desktop, but making a bugle with your own hands is not great work and complexities.

To use a traditional blacksmith forge, you need to be quite knowledgeable and skilled craftsman, especially in terms of fuel selection, which will be discussed in more detail below. Considerable experience is also required for the basis of the hearth of the hearth - the lance - and the pressurization device. The use of natural gas for heating, although it does not allow you to forge a Damascus blade or Indian damask wutz in a home forge, like a classic coal forge, it greatly simplifies the design: a gas furnace can be assembled in half an hour or an hour from 6 fireclay bricks and a few scraps of steel, and the temperature and quality of heating will be sufficient for the now so popular small art forging or smelting of non-ferrous metals and alloys for casting.

Horn device

The classic production forge is arranged as follows, see the figure on the right:

a horn table made of refractory material;
firebox (hearth) with grate;
air chamber;
air drainage;
supply air duct;
air valve;
chamber (tent) forge;
window for feeding long workpieces;
bugle umbrella;
chimney (gas outlet);
removable crucible;
hardening bath (tub, tub);
gas chamber.

The principle of operation of the forge

In order to make a bugle yourself and use it successfully, let's figure out how a bugle works, what's in it, and what can be made cheaper and simplified under conditions home use without compromising the quality of metal processing. The hearth is based on the chemical reaction of carbon combustion 2C + O2 = 2CO2 + 188.1 kcal. According to its energy yield (94.05 kcal/mol, i.e. 12 g C, completely burned, they will give 94.05 kcal of heat), it is clear that carbon is a very strong reducing agent, i.e. greedily combines with oxygen.

This property of carbon has been used since time immemorial in metallurgy for the smelting of iron and other metals: their ores are often the corresponding oxides or their derivatives. Carbon unceremoniously robs itself of oxygen, and the destitute metal has no choice but to stand out in a free form.

In the forge, the reducing ability of carbon is also used in part, as it prevents the oxidation of the workpiece. Simply, so that the metal does not burn out. But no less important here is the high calorific value of carbon: by blowing enough air into the fuel mass so that it has enough carbon, you can burn it quite quickly, and a large number of released heat and the temperature will develop high.

Blowing into the hearth is regulated in such a way that the fuel is slightly lacking in oxygen, this will completely prevent the oxidation of the metal. However, if the workpiece is overexposed in the furnace, then carburization will begin: the metal, especially steel, will become, as they say, overdried - excessively, disproportionately to the increase in hardness, brittle. An example of completely dry iron is cast iron. In metallurgy, in order to obtain structural steel from it, molten cast iron is subjected to redistribution: oxygen is introduced into it in a converter or in another way, which takes away excess carbon.

On other fuel

This is how the old coal furnace works. Initially, it was heated with charcoal, then with coke. Both are almost pure carbon. Basically the forge can also be stoked with firewood, allowing them to pre-burn to coals, i.e. to charcoal; how - see below.

The device of the hearth is greatly simplified if purified monogas, propane or butane is used for fuel. They consist of carbon and hydrogen, which is also an excellent reducing agent and, when combined with oxygen, gives even more heat. Moreover, the gas can be mixed with atmospheric oxygen in advance, even in the burner. How gas burners for a hearth are arranged, we will also understand further, but for now we state a fact: a gas hearth made of bricks can be assembled in haste, if only there was a burner, see fig. (You can also watch the video at the end of the section for how to make your own gas horn.)

However, this applies only to pure industrial monogases. Household natural gas, firstly, consists of a mixture of saturated and unsaturated hydrocarbons, which have different oxygen requirements and different heat release for complete combustion. That is, it is fundamentally impossible to set up the optimal air supply here for heating the metal for high-quality hardening or cementing.

Secondly, sulfur, silicon, and phosphorus are present in negligible amounts in the composition of natural gas. At least in the form of artificially introduced into household gas for immediate detection of leakage of "perfume" - mercaptan. If phosphorus and silicon, at the exact dosage, can still be useful (the first is for surface phosphating; the second is for improving the magnetic properties), then sulfur is the worst enemy of steel, completely killing its operational value, and irreversibly, complete remelting is needed to restore.

Therefore, household gas as a fuel for a furnace can be used, firstly, only after purification from sulfur-containing compounds. The simplest, but by no means free way, is to pass gas from a cylinder through a container with naphthalene before it is fed into the burner. He is as eager for sulfur as he is for oxygen. Secondly, to heat in the gas furnace only parts that are not responsible and not loaded in the future; say, decorative elements of artistic hardware.

Note: There is also enough sulfur in wood in excess to poison steel. But her and others, the so-called. alloying poisons can be burned out in advance, see below.

Video: do-it-yourself gas horn

The purpose of the parts of the forge

Now let's go back to the list at the beginning and see what's in the forge for what. And then we will already take up the manufacture of the forge according to the samples discussed below or independently, based on the materials and capabilities available.

In industry, the lining of the table is predominantly quartz refractory brick, which, under intense workload, lasts for decades. A homemade hearth is usually lined with fireclay bricks., cheaper and more affordable. With occasional use, it will also last for years.

A firebox with a grate, an air chamber with drainage and a supply pipe with a valve form the heart of the hearth - a lance. In industrial designs, replaceable lances are used under different ways heating and heated workpieces. For an amateur or an individual master, most often one is enough tightly mounted in a table with a solid perforated round holes grate.

Air drainage is necessary to accurately and quickly, without taking your eyes off the workpiece, to regulate the blowing. It will not be possible to forge an underheated part and it will not accept hardening; overheated and overdried, it will break under the hammer, and in the hardening bath it will lead at least, or even crack. And in any case, it will be unacceptably fragile. How to determine its readiness for forging or hardening by the type of a hot workpiece is a separate conversation. But experienced blacksmiths know that it takes seconds to release excess air into the atmosphere.

The purpose of the chamber, or tent, of the forge, together with its umbrella and chimney, is to remove flue gases from working area. There are plenty of them during the preparation of the coal mass (see below), and not one of them is good for health. The draft in the chimney needs a good one, because. the front (working) window of the tent and openings for long lengths (pipes, metal profiles) are constantly open.

As for the hardening bath and the gas-air chamber, they may or may not be, it's up to you. A hardening bath is a must if you are going to forge the so-called. damascus, damask steel products. They need thermal shock hardening, i.e. from the forge - instantly into the bath.

Note: about the manners of the past. Once upon a time, damask blades were considered the best, hardened in the living body of a captured strong enemy or, in last resort, muscular slave.

The gas-air chamber in the industry is used:

For additional drying and heating of air.
For purification of blast air from impurities and condensate.
For the introduction of gaseous alloying additives into the air.

At home, super-super special spawns do not get; the problem of condensate in production occurs when blowing from a common compressed air network. In a low-power hearth, the air heats up sufficiently, passing through the holes of the grate of the tuyere, and it is possible to purify household gas from sulfur by passing it through a layer of naphthalene, as mentioned above. In general, do a gas vent, don't do it, it's up to you.

Finally, crucible. This is a heat-resistant cap that expands the zone of extremely high temperature. It is set if non-ferrous or precious metals and alloys are melted in a furnace in a crucible (melting point of gold is 1060 degrees, silver is 960, copper is 1080, brass and bronze is 900), parts are cemented in a muffle, etc. It makes no sense to look for an expensive ready-made crucible; in a home forge, it will be completely replaced by a dozen fireclay bricks laid out dry in detail. In this configuration homemade bugle will replace the expensive one.

How do they heat the horn?

To finally take on your own forge, it remains to find out, but how to drown it? Then it will be easier to understand the designs.

The best fuel for a forge is fine coke. Blacksmiths call it koksik, the name was adopted by merchants. If coke is on sale, but there is coke in small package. Koksik costs, looking to the region, 3 times more expensive than coal, but it takes 1 forging with skillful handling 4-5 times less.

Coke is practically pure amorphous carbon, carbon. Really clean: coke oven gas is a valuable chemical raw material, so metallurgists don't cheat. It ignites at 450-600 degrees, so double kindling is needed: coal is kindled with wood, and a layer of 150-170 m of coke is applied to it and the blast is turned on to the maximum. When the coal burns out (this can be seen from the flame), the mass of coke is raked, leaving a layer on the grate 1/3-1/4 of the height of the entire heap, a billet is introduced into the hearth and raked in burning fuel. The blast is reduced to the norm for this operation and they wait until the part matures.

To work with Damascus, you need charcoal, it lights up at a lower temperature and burns out faster, because. preserves the microporous structure of wood. And also, like activated carbon in a gas mask, it additionally absorbs doping poisons. The fact is that damask steel is forged from a bundle of wires or bars of different hardness. The product itself is obtained by their mutual diffusion during forging. The process is very delicate, and the adjustment of the blast requires jewelry, and the light porous charcoal responds instantly to the manipulation of air drainage.

If you heat with coal, you need to let it burn out to carbon, i.e. volatile components, the same coke oven gas, must burn out. This again can be seen from the color of the flame. But such a complete extraction of volatiles, as in a coke oven battery, cannot be achieved directly in the furnace, so that decorative or medium-quality household products can be forged on coal. As a rule, one load of coal is not enough and it has to be burned. An additional load for afterburning is placed on the side of the hearth on the table and, as it burns out, the resulting carbon is raked onto the workpiece.

In general, firewood is heated in the same way as coal, but only hardwood. It’s just that a bunch of firewood will burn to ash rather than completely release volatiles and form coal. In addition, it is impossible to allow unburnt chips to get on the part, there are too many impurities in the wood that are harmful to steel. Therefore, firewood for carbon in the hearth is burned in the shell, see fig. The additional load is burned out by placing it close to it, and as it burns out, the coals are transferred to the shell with tongs.

Let's take the bugle

For a novice blacksmith, to gain experience and flair, it is best to quickly make a mini-forge from 6 fireclay bricks, see fig. An ax blade to shave, or hunting knife you can’t heat it for hardening, but you can heat a trifle for artistic forging, the ends of a long length for forging or bending, or melt a precious flower in a crucible.

Shelves of the grate from scraps steel pipes, and the grates themselves are made of a steel strip 4-6 mm thick. The grates must be screwed in at an angle to capture the blast flow, as shown in fig. Fuel - coke or coal. Ignition and blowing - with a blowtorch, gas or air-fuel burner. If a blowtorch is used, an asbestos partition with a window for the nozzle must be placed between it and the furnace: the furnace radiates intense heat and the lamp reservoir may explode. They use this mountain only in the open air, because. there is no umbrella with a chimney.

Note: more interesting option- a small bugle in haste of the minimum cost, see video:

Portable

The next design is a portable horn from ... goose. The design is clear from Fig. Lining - fireclay marl mixed with fireclay sand (ground fireclay bricks, commercially available). Roasting of the lining after drying - in the course of work.

Pressurization is not necessarily a fan from a manual siren, as in fig. You can use any suitable one, see below, by attaching it to the metal corrugated. This, by the way, will make working with a long length more convenient. In this case, at the dead end of the duct, air drainage is necessary, like for a mobile forge, which will be discussed later.

The capabilities of the hearth from the goose are wider than those of the 6-brick one, because. the workspace is larger and open at the top. But there are also significant flaws:

Non-separable design: when cleaning the lance (see below about the stationary hearth), the soot falls down and clogs the perforation of the air duct, even if its holes are oriented sideways or downwards. For cleaning it is necessary to break the lining.
Works only on coke or charcoal, tk. there is no table with space for burning out.
Expensive operation: carbon consumption is comparable to that of coal in real forges.
Low operating temperature, up to 900 degrees, because a lining that has not been burned properly will crack at a higher temperature.

About cavalry and sewing machines

Once upon a time, every cavalry squadron of all the armies of the world had a portable forge on the farm with a foot drive from a crank mechanism for forging horseshoes and horseshoe nails. He was called the cavalry, see fig. If we talk about non-volatile bugles, then this is much more convenient than a fan from a siren: both hands are free. Moreover, savvy horsemen taught horses to put pressure on the pedal with their hooves.

Now the cavalry horn can only be seen in the Museum of the Red Army. But - we will show ingenuity - the old Sewing machines with a foot drive are still in operation and sold. And this is the same crank with a drive pulley of a suitable diameter and a solid bed for the table. Plus wheels on which you can roll the bugle.

What kind of fan do you need?

Below we will move on to designs that are already quite functional, which require a full-fledged blast. And electricity for the fan is everywhere. But what kind of fan is needed for a forge? Once upon a time, horns were blown with bellows; who are curious about how the bellows are arranged, see fig. on right.

Note: it was from the remains of bellows of ancient times that archaeologists established that metallurgy among primitive peoples had a mystical and sexual meaning - from Scandinavia to South Africa the clay fitting of the forge was made in the form of male genitalia, and the nest under it in the forge - female.

As for productivity, 200-250 l/min will be quite enough for a stationary furnace on coke. That is, the power of the fan motor is sufficient from 80-100 watts.

More importantly, we need to push air through a rather dense mass of sintered fuel. Therefore, when choosing a fan, first of all, you need to pay attention to the pressure it creates at zero performance, the so-called. limit pressure. The meaning of this parameter is simple: the fan will create the maximum pressure by forcing air into a closed cavity.

For a forge, you need a maximum pressure of 220-230 mm. rt. Art., which corresponds to approximately 0.3 ati. Axial fans (impellers) are created only by industrial ones, such as VN-2 or its analogues. Household exhaust and industrial cooling systems are not standardized at all in terms of maximum pressure and, as a rule, they do not create the necessary.

In addition, they bring air up to the maximum pressure slowly, in minutes, and for fine forging and forging work, the blast must be changed in seconds. It is useless to install a receiver: when the valve is opened, the air in it will expand along the adiabat, which at 0.3 ati will only give a zilch.

Total output: needed to inflate the forge centrifugal scroll fan . You don’t have to look at the specification, any centrifugal fan will give the required maximum pressure according to the very principle of its operation. It is best to take snails from radiation protection systems military equipment and they have high performance. True, the power supply is 12, 24 or 27 V direct current, so you need a transformer and a rectifier of the appropriate power.

Any old household vacuum cleaner will work fine, but here you need to consider that its power will almost always be excessive. You should not reduce it with a LATR or a thyristor regulator: the motor will work in the heavy mode of excessive slip of the rotor and the resource of an already worn out old man will be small. It is best to make a wide air drainage in the tuyere, as in the stationary furnace described below.

Mobile

Here in fig. - drawings of a deservedly popular design: a fully functional mobile forge designed for outdoor use. It was this kind of device that was meant when thinking about cavalry and sewing machines.

Pay attention to the node marked with the number 1. This is a fine blast control drain. The drainage tube slides in and out, and at the bottom a longitudinal row of small holes, 1-2 mm in diameter, is drilled into it. By passing air into the drain, you can very accurately adjust the boost.

Stationary

Stationary bugles make experienced craftsmen according to their anthropometric data. A piece of red-hot orange iron weighing several kilos in tongs is an extremely traumatic object, so the ergonomics of a stationary forge must be perfect.

Note: in the novel by A. N. Tolstoy "Peter the Great" a case is vividly described, how the still young tsar-worksman received a decent scolding from a forced blacksmith for awkwardness when welding the anchor paw. Only huge physical strength Petra then prevented an industrial emergency.

We take sizes

Approximate dimensions of the stationary hearth are shown in fig.

It is approximate, but the height of the table and its dimensions must be determined exactly:

We become straight, feet shoulder-width apart. We bend the right freely lowered arm at the elbow.
The assistant measures the distance from the elbow to the floor. Add 5-7 cm to it, this will be the height of the table.
Now we take the largest ticks in the same hand, the assistant measures the distance from the stomach to the ends of their sponges.
We add 10-12 cm to it, we got half the length of the diagonal of the table.
We take the length of the side of a square table equal to 1.4 of the length of the half-diagonal (0.707 of the full diagonal).

Note: it is not necessary to make the table round, because. parts with pliers will have to be taken differently. And rectangular - you can, if you work together with an assistant.

Design

The sequence of manufacturing a stationary hearth is visible from fig. It is better to lower the air of the lance with a pressurization from a vacuum cleaner or a snail of an auto-stove, and at the same time make the air drainage damper (items 4 and 5) retractable forward. It turns out air receiver a sufficiently large capacity, and the damper can be pushed in and out with the toe of the shoe.

Also pay attention to the one-piece grate, pos. 2. In this case, it is special for bugles. The secret is in the intersecting hollows dividing the slab into squares. They accumulate soot. If holes are drilled in a smooth plate, then after each forging they will have to be cleaned with a steel bar.

But why can't the grate be made of slats, like in an oven? Because the mass of fuel is not sintered uniformly. In the gaps between the slats, the air flow will jump to where it is freer for it to exit. In that place, the temperature will be higher, and the entire workpiece may be overdried in spots. An amateur master will not notice this by sight, but under load, local fragility will affect. And passing air through a two-dimensional regular structure (one-dimensional furnace grate) reduces the unevenness of air distribution by an order of magnitude. If the grate is three-dimensional, as shown in fig. with a hearth device at the beginning, then the uneven distribution of air has practically no effect.

But what if there is no place to take a special grate? Then an acceptable output is a completely homemade lance with a concentric arrangement of holes with a diameter of 8-10 mm, see fig. on the right, such a system does not clog so quickly and blowing over the area provides more or less uniform. According to the principle of operation, it is similar to a shower diffuser.

It is impossible to pressurize the air shower with a vacuum cleaner, the fuel will blow out. You need to take a snail from an auto-stove or the like. In this case, it is also undesirable to regulate the blowing by drainage, the boost optimal for blowing uniformity is rather weak. It is necessary to build a throttle valve into the air duct, and make the bottom cover of the lance removable only for cleaning.

Gas-burners

And in the end we will give drawings of several burners for gas furnaces. For artistic forging, they are quite suitable, and, whatever you say, it is the most demanded of blacksmithing. All these burners are direct-flow injection burners. Much more efficient and versatile vortexes are too complicated for self-production.

The first one, in Fig., is the most difficult. To do it, you need to be a turner-miller of at least 5 real ranks. But it works on any gas (except acetylene, see below!), gasoline-air mixture and gives a very powerful boost: it can also blow a large stationary hearth, described above.

The next one (see the figure) is simpler and contains fewer details, although even here it is necessary to accurately sharpen shallow cones. The blower is also great, but it only works on propane. For butane, a very narrow nozzle is required, and butane is used little.

It is necessary to grind clean the outer surface of the D1 injector and drill the nozzle in one setting. The nozzle is drilled with a carbide drill and run clean with a reamer. This is the main drawback of the design: a small, precise tool is required, which is not always and not always available.

Below in fig. two burners are simpler. On the left - chiseled universal for household gas or propane. A small mobile forge can blow through at most, but turning parts can be done by an average turner. You just need to master the technology of landing parts in a hot fit. Which, however, is not difficult.

On the right is a homemade burner. Most of the parts, including the nipple, are from a bicycle. From the lathe, you only need to grind the smallest sprocket from the bicycle gearbox to size. This burner is omnivorous: propane, butane, household gas cocktail, gasoline air. But it can only heat the small closed brick hearths shown at the beginning.

Note: never feed these burners with acetylene! You will burn the metal in the furnace and it will not take long before the explosion!

Finally

Well, now we know how to make a bugle. And what to do with metal in it is a separate big topic. Blacksmithing from the forge is just beginning.

Updated:

2016-09-12

Making a blacksmith's forge with your own hands is far from the most difficult task. At the same time, you will get the opportunity to create metal masterpieces at home. Of course, making a forge with your own hands makes sense only if you are going to work with metal, forge some products.

Photo of a forge

Forged elements are actively used in industry and everyday life. It can be as huge complex structures, and the simplest small crafts.

To be able to forge metal, it is necessary to have a forge and a device that will heat the metal to the required temperature of 1000-1300 degrees. How to achieve this at home? That's right, you need to build a forge with your own hands.

The device of the forge is just designed to heat metal blanks to high temperatures.

Forges have the same principle of operation, and the devices differ only in the type of fuel used. This affects the type of construction.

Modern blacksmiths who prefer to work at home use coke as fuel. This is due to the fact that coke provides a high temperature at low consumption, emits a minimum of waste.

The nuances of self-production

How can you make a homemade blacksmith forge? To do this, you will need drawings of the model of the heating device that suits you and the room where the equipment will be located.

Horns differ in the types of heating chambers.

Closed heating chambers. They are the most efficient, as they minimize fuel costs, providing excellent heating of the workpieces. But the blanks themselves are limited in size, since they depend on the dimensions of the chamber.
Open chambers of a warming up. This design provides that fuel is poured onto the grate, and air is supplied from below. The metal blank is placed on the fuel. Although the fuel consumption is somewhat higher, larger blanks can be used.

How to make a blacksmith's forge in order to be able to forge iron at home? Consider each stage of the construction of the structure.

Photo of a blacksmith's forge made by hand

Table. The table is the basis of a homemade forge. The drawings show that it is quite simple to build this element. Usually the height of the table is up to 80 centimeters, and 5 millimeters thick metal is used for the cover. Working surface became can have different sizes. It all depends on what kind of metal blanks you are going to work with. Another option for building a table is to use the corners to create a frame. A brick and a grate are laid inside it. The grid should be centered.
The grid is mounted in a hole made in the table. Then refractory bricks are closed on all sides. Select the height of the table directly to your height so that the structure is at waist level.
Blowing. In order for the forge device to work effectively, it needs high-quality air blowing. Due to oxygen, the temperature rises, the metal begins to melt. Traditional horn designs used a foot-operated blower. But now everyone has the opportunity to use electricity, so the best solution is an electric fan or old vacuum cleaner. The vacuum cleaner delivers the right amount of air. With a speed controller, you get a chic homemade bugle.
Now all structural elements are assembled into a single system - a home-made metalworking forge.
Pour on the grate required amount fuel. First, use wood chips and medium wood, after which it is the turn of coke. Turn on the blower, place your workpiece over the fuel. A small amount of coke may be sprinkled on top of the iron. If there is no coke or there are large stocks of wood taps, you can use them.

This is a model of a simple blacksmith's forge. If there is a desire or opportunity, you can significantly improve your own blacksmithing equipment, bringing it closer to the features of an industrial forge.

What has an industrial forge

Professional blacksmiths use industrial forges, which differ increased efficiency and high reliability. It is almost impossible to make an industrial forge on your own. But somehow get closer homemade model to the ideal is quite real.

What is the difference between an industrial forge, and what components are included in its design?

Air nozzle. Homemade forges use the hose of an old vacuum cleaner to supply air instead of a nozzle;
Refractory brick. There is a complete analogy between home and industrial devices;
Grate. Most homemade forges involve the use of a grate. Many people make it from old thick-walled pans;
Nest for solid fuel. This socket allows you to conveniently load the required amount of solid fuel. It will not be a problem to equip a homemade horn with a similar element;
Frame bricks. It's already stationary devices which are laid with bricks. For a simple forge, such elements are already superfluous;
Air supply fan. We considered an example with a conventional vacuum cleaner, which does a good job of pumping air. If you like, you can use fans or other similar devices;
Metal carcass. On its basis, the table is held;
Air chamber. Homemade forges do not have it, but if you need professional equipment, equipping the device with a camera will not be superfluous;
Ash pan. If you intend to regularly use your forge at home, we advise you to equip it with an ash pan. So it will be easier to take care of the device;
Horn casing.

What exactly to complement your blacksmith device - decide for yourself. At the same time, we advise you to follow a few recommendations in order to increase the efficiency of the device.

The fuel can be coal, wood and coke. Although coke is more expensive, it consumes 5 times less than coal, emits less soot and waste. Fine coke is the most efficient type of furnace fuel.
An alternative type of fuel for the forge is gas. And from cylinders or lines. When using gas, you do not need a grate. The advantage of gas is the ability to control the heating temperature and its availability.
An exhaust hood should be installed above the mountain, consisting of metal 4-5 millimeters thick.
If the horn runs on gas, holes for the burner must be made on the sides.
Forging devices need smoke removal systems. This is a pipe with a height of 5 millimeters, the cross section of which is 30 by 30 centimeters.
A good replacement for a vacuum cleaner is a stove fan that is installed on cars.
If done in back wall hole, ventilation will be much more effective.

After looking at the photos of the bugles and studying the video guides to their self-manufacturing, we can conclude that there is nothing complicated in the construction of such units. Another question - do you need it?

In blacksmithing, a forge is used to warm up and heat up metal blanks before heat treatment. The operating temperature in this device rises to 1200 degrees. By design, the device can be stationary and mobile (that is, it can be placed directly in a specially equipped forge or transferred to a place convenient for work). Equipment for industry is completed different devices, For domestic use the bugle is made in the simplest version.

Features of a household blacksmith forge

Due to the high cost of melting plants, not every user can buy such equipment for special purposes. For domestic needs, it is not difficult to assemble a gas forge forge with your own hands subject to the correct determination of the form, power and structure of the pressurization system. A simple household forge for artistic forging or casting from non-ferrous metal can be assembled from several fireclay bricks and sheet steel.

Making a horn at home for working with ferrous metal is not difficult. The simplest design can be made from a metal container, in the side of which it is necessary to make a hole for a gas burner. The fuel supply system can be assembled from a piece of pipe and a coupling, for supporting structure long bolts will fit under the container. The lining of the gas chamber is carried out by filling a solution of alabaster or gypsum, sand and water.

Horn must be equipped protective cover, a ceramic tube or a suitable bottle. After lining and drilling a gas supply hole, the device is installed in a convenient place, but at a distance from flammable materials. The advantages of the design include the ability to move the furnace, adjust the degree of heating of the workpiece, which is especially convenient when working with different forging materials.

The principle of operation of the installation

Before proceeding with the assembly of the thermal installation, you need to understand the principles of operation of a homemade forge for forging metal to simplify the design of the stove for home use. The operation of the device is based on the energy yield during the combustion of a mixture of carbon and oxygen, the percentage of metal release in molten form. During the smelting process, carbon stops the oxidation reaction of the metal, the constant blowing of gas into the fuel quickly increases the temperature in the hearth.

The process of heating metal requires certain skills and specific knowledge. It is not enough to assemble a mini-forge with your own hands, you need to learn how to control the supply of oxygen to the fuel, the volume of which should be no more than 95%. If the workpiece overheats, carburization of the metal occurs, the steel becomes brittle, turning into cast iron.

Designing the Blueprint for the Future blacksmith fixture, Special attention should be given to the type of energy substance that affects the design of the hearth. By type of fuel for the furnace is:

gas (butane, propane);
liquid (diesel oil, fuel oil);
solid (charcoal, coke);
mixed (gas-liquid).

Depending on the planned work and the size of the workpiece, the thermal furnace can be with an open or closed hearth zone. Home master it should be remembered that household gas can be used in the hearth only after preliminary purification from sulfur by the method of "running" through liquid naphthalene. Products from heated gas burner metal cannot be used as loadable parts.

The main requirement for the safety of the master is the installation of a powerful forced ventilation system, even if a household soldering machine powered by bottled gas is used for the forge. The device will allow you to engage in the manufacture of decorative elements of the interior and exterior in own garage.

Making a stove from a blowtorch

Making a hearth for forging with your own hands, blowtorch you need to install in a recess, around the perimeter of which lay fireclay bricks with a grate. When laying refractory bricks, it is necessary to observe the distance between the enclosing elements in order to ensure the entry of air masses into the combustion chamber. The angle of the blocks relative to each other building material determined by the master.

Charcoal or coke is poured into the recess, equipped with bricks on the grate, a pipe is put on the blowtorch, which is brought under the grate. The blank for forging is placed in the gap between brickwork, coal concentrate is ignited from below. To remove smoke, a probe, tent or chimney is installed above the grate.

Solid propellant forge device

The simplest model of a solid fuel device for a private forge is an outdoor open oven, which does not require the installation of a ventilation system. The construction of the structure provides for the pouring of a reinforced concrete base; a wall brick must be laid at the base of the structure. The table is set on comfortable height , a hole for the blower is left in one wall.

The mountain hearth is laid out from fireclay bricks supported by steel corners; a cavity for the grate is left in the middle part of the structure. A chimney or a probe will help to ensure sufficient draft in the hearth, the air supply system is mounted at the final stage construction works. Installation in the chimney will help to strengthen the draft electric fan or installation of bellows.

In a home forge, a container for hardening parts and a gas-air chamber are not mandatory elements. They can be useful in the case when, in the process of working with damask steel, it is required to carry out thermal or shock hardening. In the gas-air chamber is carried out:

drying and heating of oxygen;
filtration of oxygen from condensate and impurities;
mixing air with filler substances for steel alloying.

To melt precious metals and create an alloy of non-ferrous metals, it is necessary to make a crucible from a heat-resistant material. Made in the form of a cap, the device allows you to increase operating temperature in the oven without the risk of overheating the workpiece and the formation of soot.

Home forge on gas

For the manufacture of a simple home forge on gas, you can use parts from an old bicycle. If on lathe to turn the "asterisk" from the gearbox, the device can operate on butane or propane, heat closed small-volume horns. An important condition use portable design is a ban on the operation of the burner with acetylene, since the high temperature of the flame can burn the former "asterisk", and the furnace will simply explode.

It is not difficult to assemble such a device, while a home-made forging forge is not much inferior to industrial ones, but it is much cheaper. The main thing is to observe the safety rules in the manufacture and use.