high strength of the material and pliability to processing;
high efficiency;
affordable cost;
ease of self-manufacturing;
mobility. A metal oven is usually a separate structure that can be moved to another location if necessary;
effective heating of the room due to the high thermal conductivity of the metal;
metal cannot damp, which is important for bricks with infrequent use.
Metal furnaces "Breneran"
At the moment, metal stoves for summer cottages and houses are produced by many manufacturers. Of course, in order to make the right choice, you should familiarize yourself with all the offers on the modern heating equipment market. After all, the range of such units is quite wide. All products can be divided into high-quality and expensive, produced by foreign manufacturers, as well as local-made equipment, which has average characteristics and a fairly high cost. The choice directly depends not only on the requirements, but also on the amount that you can spend on the oven.
Products of the brand "Breneran" outwardly resemble a cylindrical container, which is surrounded by pipes of a sufficiently large diameter. It is worth noting that such a metal stove for a home is capable of operating for a long period of time after the first fuel is loaded. The large diameter of the pipes at the outlet allows, if necessary, to equip the unit with air ducts. That will allow you to heat the neighboring rooms.
disadvantages
But, despite the advantages of metal, such furnaces also have some disadvantages:
Unlike brick ovens, metal walls do not "breathe". The brick absorbs moisture, and in the process of heating it gives it back to the room. Therefore, in rooms with metal stoves, the level of humidity decreases.
Lower heat capacity. The metal oven cools down quickly. Brick analogs stay hot longer, continuing to heat the room. Alternatively, you can make a metal oven with bricks.
In this case, a metal stove is built into a brick structure. This allows you to combine the positive properties of both materials, but at the expense of mobility.
Fragility. Metal burns out over time, especially thin. If used infrequently, a metal stove will last a maximum of 20 years. But, if you use it every day, the metal will only last for 2-3 seasons.
Disadvantages of ovens "Breneran"
Such a metal stove for a home is considered ideal if you only need to heat one room. The operation of such equipment causes some difficulties if it is necessary to heat several rooms at once. In this case, large heat losses are observed.
Another drawback of such equipment is its ill-conceived design. When operating such stoves, an unpleasant smell is felt in the room, which arises as a result of condensate and other substances flowing into a separate container. This is due to the location of the chimney tee and branch pipe. In the Breneran unit, they are located on the rear wall. Experts recommend creating a forced draft in the room where such a stove is located.You can also solve the problem by installing the stove in a separate specially equipped room.
Metal selection
If you plan to make a metal stove with your own hands, you should take care of the choice of material in advance.
Different metals differ significantly in physical and chemical properties, which directly affects the quality of work and durability of the furnace.
In the photo of metal stoves, you can see different models made from different materials. When choosing a metal, first of all, one should take into account its properties, specific needs and operating conditions.
What you should pay attention to
To solve the issue of heating a private house or summer cottage, many install brick ovens. Such units are large enough and cannot be moved or moved if necessary. It is for this reason that metal stoves have become popular. When choosing such a product, it is necessary to pay attention not only to its characteristics and features, but also to the needs of those who will live in the room. Among a wide range of heating equipment, household, heating and cooking, heating and special-purpose units are in great demand.
Aluminum alloys are generally not used to make furnaces. Some craftsmen make such ovens from milk cans. The only advantage of such a can is its large capacity, sufficient for the oven.
But, unlike steel, aluminum has a significantly lower melting point. It starts to melt at 660 ° C.
To effectively burn a tree, you need a temperature of 400 ° C. And in order to exclude the formation of harmful gases, it is necessary to ensure a temperature of 600 ° C. Accordingly, aluminum is not suitable for making ovens.
Plain steel
The thermal resistance of ordinary steel is limited to 400 ° C. Usually a material with a minimum thickness of 4 mm is used.
For rare use in relatively warm climates, this option is appropriate. Although such a stove will only last 2-3 years, perhaps 5 years if used very rarely.
But, if the oven is to be used every day, this material will not work. With daily use, a plain steel stove will last no more than 1 season.
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Metallurgy of antiquity. Part I. Blast furnace in Istie
Hello dear friends! We all, one way or another, know about buildings of the past that have not been surpassed to this day, for example, St. Isaac's Cathedral, the Colosseum, or the Eiffel Tower, various palaces and fortresses, of different times.
However, few people think about how these objects appeared, or rather because of what. Indeed, strictly speaking, without developed metallurgy, no grandiose construction is simply impossible, neither in the past, nor in our time. What is metallurgy? It is literally a ticket to the club of the elite. The people who did not subjugate metal are considered primitive. That is why our great iron past is passed off as handicraft. After all, metallurgy, so to speak, is the very first link, the foundation, of the technological development of any civilization, because without metallurgy, it is impossible to manufacture instruments of labor and production, without which, in turn, neither construction, nor agriculture, nor military operations are possible. More precisely, it is possible to fight and dig the ground, of course, with sticks, but this is no longer a civilization, but only its formation.
Moreover, only one direction in industry cannot develop: the development of metallurgy will automatically entail the development of related industries, everything is interconnected. Thus, the general level of development of industry and the state as a whole depends on the level of development of metallurgy. Accordingly, in order to state at the official level about the worthlessness of a state or people, it is enough to assert that this people, or state, did not have metallurgy at all, or its development was in its infancy.
How much do we know about the metallurgy of the past? I think many have heard about the so-called "Bronze Age", but today we will not consider the production of bronze, if only because bronze ore does not exist in nature, bronze is an alloy, and soon there will be a separate conversation about it, and we at the moment I am interested in the full cycle, from ore mining to the finished product. And what do we have about this, say the official sources? So, the first official historical note:
The production of iron in the territory of Russia has been known since time immemorial. The ancient iron, produced by handicraft methods, is called "blooming" or "swamp" iron. As a result of archaeological excavations in the areas adjacent to Novgorod, Vladimir, Yaroslavl, Pskov, Smolensk, Ryazan, Murom, Tula, Kiev, Vyshgorod, Pereyaslavl, Vzhishch, as well as in the area of Lake Ladoga and other places, hundreds of places with the remains of smelting pots, raw forges, the so-called "wolf pits" and the corresponding tools for the production of ancient metallurgy.
During excavations in Staraya Ryazan, in 16 out of 19 dwellings of townspeople, traces of "home" cooking of iron in pots in an ordinary oven were found. In fact, the Iron Age lasted for several millennia. So in Arkaim, the metal was smelted already 4000 years ago.
The Western European traveler Jacob Reitenfels, having visited Muscovy in 1670, wrote that "the country of Muscovites is a living source of bread and metal." So, for example, not far from Novgorod in the Ustyuzhna region there were so many "forges for making iron" that the Novgorod governor, who visited these places, thought that he "drove into the outskirts of a volcano." Furnaces for making iron stood everywhere, the number of living monuments of this "industrial boom" still amazes modern archaeologists who are excavating the "cultural layer" on the Russian platform.
Our people know how to cook metal, even in pots in a home stove, we can say that in our blood. Iron in Russia was smelted back in those distant, deeply pre-Christian times. The names of the Russian people literally shout to us about the prevalence of metallurgy throughout the territory of ancient Russia: Kuznetsov, Rudnev, Kovalev.
In short, there are a lot of iron traces of our past, and now, friends, I suggest you take a trip to one of these places - a metallurgical plant in the village of Istye, in the Ryazan region, and on the example of this plant, to think about metallurgy in general ...
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Location of objects
The complex itself consists of five objects, these are the remains of a blast furnace, a factory building, the Church of the Nativity of Christ, a factory pond and a dam. And they need to be considered as a whole, however, due to the large amount of information, we will talk about the Church of the Nativity of Christ in the second part of the article. About the pond, now I will just say that its shape provided a water supply to all technological links of the plant. The dam is located on the Istya River.
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Remains of a dam on the Istya river
True, in this place, the river just resembles a stream, and the platinum itself, at the moment, is just a blockage of stones and pieces of concrete slabs. However, in this rubble, there are blocks of old bricks, piled here during the demolition of ancient structures.
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Brick blocks in the dam
But the remains of the factory complex are much more interesting, and we will begin our inspection, with a blast furnace, and for complete objectivity, we read the second official historical reference, already at this place:
On the territory of the village, in the 12-13th centuries, there was a settlement in which iron mining was carried out. After the "Mongol-Tatar invasion", the settlement was abandoned.
The modern village of Istie owes its revival to the iron foundry, built in 1715 by decree of Peter I, which the Ryumin family of merchants began to build, taking advantage of the fact that ore deposits were discovered near the village of Zalipyazhye (now a village). / On the question of the presence of ore on the Ryazan land, I suggest recalling the Drunken Forest. ]]> Link to article here.]]> /
In 1717, the Istyinsky plant gave the first melting. In the same year, 1717, a needle factory appeared in the village of Kolentsy, and in 1718 - a second one, in the neighboring village of Stolptsy. From that time on, throughout Russia, the dress-down shirts of the peasants and the magnificent outfits of the nobility were sewn with Ryazan needles.
In 1773, the entire complex was bought by the plant owner Pyotr Kirillovich Khlebnikov, the owner of the Blagoveshchensk copper-smelting enterprise in the Ufa district. His son Nikolai Petrovich Khlebnikov began to reconstruct the factory complex he inherited, he invited the chief architect]]> Vasily Petrovich Stasov]]>. In his memoirs, Stasov describes what he built in the Ryazan possessions of Khlebnikov, a quote: “two vast estates with gardens, a large house, services, greenhouses, a menagerie, a theater, an arena and various recreational activities. On the same lands of the same nobleman, there are two buildings for two manufactures: one for iron and the other for the production of needles, with two dams on two rivers, with a three-span bridge made of hewn stone, with various other buildings for work and warehouses ”, end of the quote.
Both manors looked more like small palaces than work buildings. Even the meager remnants of the Ist'insky complex that have survived long ago, which have long lost their former splendor, nevertheless testify that it was once one of the most outstanding Ryazan district estates.
After the death of Nikolai Khlebnikov in 1806, all possessions were transferred to his sister Anna, married to Poltoratskaya. During her reign, the construction of the grandiose Nativity of Christ Church was completed, the architect of which was also Vasily Petrovich Stasov.
In the late 50s of the 19th century, the Poltoratskys owned an iron foundry, an iron-making, machine-building factories in the Pronsk district, two needle factories, one pin factories and one wire factories. They employed about 1200 people.
At the present time, the two-storey main house and two outbuildings of the 1790s have been preserved from the whole complex; the Church of the Nativity of Christ, built by Anna Petrovna Poltoratskaya in 1816; an abandoned factory building and the oldest blast furnace in Eastern Europe, recognized as a historical monument. All the surviving buildings are made in the style of "classicism" by the architect Vasily Petrovich Stasov.
Read more about Stasova, if anyone is interested,]]> read it yourself here]]>, there are a lot of non-joins by dates.
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Blast furnace, view from the complex
According to official information, it is the oldest blast furnace in Eastern Europe. Now I will not touch upon the question of whether there was Peter I or not. We are now interested in the age of the blast furnace, because, even according to the official history, it is more than 300 years old, and this is not officially hidden. It is simply not advertised. Here I want to note that in my opinion, the stove is much older, but even 300 years old is a good age.
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Blast furnace, view from the pond
I want to clarify right away that this structure is just a remnant of the furnace. She had at least a pipe, and there were two more chambers on two opposite sides.
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Approximate pipe height
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Broken walls
Friends, I ask you to pay attention to details such as soot and the thickness of the screeds.This whole structure was a furnace, but there are practically no traces of soot, soot is visible, mainly only in places of later alterations, I will also tell about these alterations further.
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Ties size
And the thickness of the screeds, you can see for yourself, in comparison with Mikhail's palm, and this particular screed is not forged, it is rolled, and it was laid during the construction of the furnace, and it was officially built in 1715.
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Screed-rolled
Green glass is fused brick.
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Fused brick
This is what a brick looks like when it is melted in a metallurgical furnace. The glazed layer is very thick. The melting temperature of iron is one and a half thousand degrees, so even chamotte, that is, refractory, brick was fused into a single structure, and already under it, ordinary brick was fused, from which the load-bearing walls were laid.
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Fused brick
The quality of the masonry of the stone walls on the outside is much worse than the brickwork, as well as the masonry under the arches.
This is an important detail, by which we can conclude that outside, this is a later alteration, strengthening of the furnace, its repair. The stones in the wall are different, some are natural, some are cast.
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Built-in top
The top of the service building is visible. These offices are currently located on both sides of the forge, but judging by the remains of the walls, such premises were located on all four sides.
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Plan: top view
These rooms are needed to cool the furnace body and heat the air that is blown into the furnace.
Here you need to understand that the air was supplied into the furnace not just by natural draft, but forcibly, under pressure, through the side arched openings, in which the tuyeres stood.
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Lances
This is how any blast furnace works, even nowadays. And for air supply, a whole system of pipes and compressors is used, which were located in these rooms, as well as outside.
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Niches
By the way, outside at some height, there is a niche, really, for statues? This is precisely a niche, there are no passages in it, neither to the sides nor down, the floor in it is lined with stone.
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Punched hole. 18th century stamping?
Here is another interesting screed, a hole in it is punched out by stamping. How and with what was it pierced? With a hammer and a chisel? I emphasize that there are a lot of screeds.
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Screeds
All the walls are pierced with them, and from the outside, all the screeds are tied into a single reinforcing frame. But such forged loops, at the ends of the ties, we have repeatedly seen in places associated with a certain religious cult.
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Tie hinges
About the fact that this stove, initially, was higher, and now, it is filled up by about 1-2 meters, I think you have already guessed for yourself, by low and disproportionate arches.
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Backfilled arch
But this is not all the evidence of a backfilled stove. According to the technology of the blast furnace, the forge, with liquid metal, is located below the tuyeres, and the flyers, along which the molten metal flows out of the furnace, is located at the very bottom of the forge, which is actually logical, since the iron flows by gravity.
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Blast furnace diagram
And now we see the level of the ground, approximately at the level of the tuyeres, through which the air was supplied to the furnace. Accordingly, everything else is below ground level. This is all that remains of the blast furnace, but we will return to it later today, and now let's take a look at the factory building, or rather, at what remains of it.
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Factory building
Inside the building, a forest grows. Here the trees, apparently, are not cut down on purpose, so that everything would fall apart faster. For example, the Church of the Nativity of Christ, which stands a little further away, and about which there will be a story in the second part, they began to restore it. The money was found for this. Naturally, the church is needed, but our iron past is not needed, and the trees, gradually, with their roots, break down the stone walls, and soon the complex will collapse on its own.
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Backfilled arch
The fact that the building is filled up can be clearly seen from its end, from the side of the pond.The height and width of the arch are not proportional, and the door is pierced above the arch. On the back of the door, there is a single hinge, and judging by the width of the arch, the second, somewhere lower, is two meters.
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Hinge under the arch
And these are counter-force friends, the real one. Remember where we saw them before? ]]> Here's a hint]]>.
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Buttress
Just do not write in the comments that counter-forces are put for beauty. It is quite possible that this is a later renovation, since the counter-force is not tied to the main wall, but, nevertheless, it is made with the same brick and with the same mortar.
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Embroidered seams
By the way, the seams of the main wall of the building are embroidered, so it was not planned to be plastered.
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At this angle, it seems that 105, or even 104, but if you look directly, then 106 cm
The thickness of the walls is 106 cm, therefore, laying an arched passage between adjacent rooms inside a single building, two brick plugs were simply built here, on both sides, flush with the main wall, and between these plugs there is a lot of space where debris gradually accumulates.
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Blocked passage
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Rubbish between the walls
Due to such a thickness of the wall, this opening was not even clogged so that the material would not be wasted. I repeat, this is an internal load-bearing wall, between adjacent rooms of the same building, therefore, the thickness of this wall has nothing to do with heating and cold winters, which, in my opinion, did not exist. Why there were no winters,]]> is explained in this article]]>.
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Ground level
Here, the ground level is outside, flush with the windowsills, but the level is lower from the inside. Has this building subsided? Or was it how they built it?
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Columns, at the entrance to the former cinema
What exactly was built, these columns, from modern ceramic sewer pipes, because in Soviet times there was a cinema here.
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Columns of pipes
Friends, now I propose to think a little about what you saw. Any metallurgical plant starts with raw materials, so the very first thing to think about is the extraction and delivery of ore and fuel, ore dressing, as well as the dispatch of finished products. In short, let's talk about logistics.
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Ore waste heaps
To make it clearer for you, I will literally tell you in a nutshell how the blast furnace works. The main condition for the operation of a blast furnace is a continuous smelting process. Actually, the blast furnace differs from the same cupola, which, in fact, works on the same principle as a blast furnace, but only with smaller volumes, and the cupola itself is smaller and its walls are thinner, and the cupola works according to the scheme: fired up, melted how much you need and repaid. This is not the case with a blast furnace, a blast furnace is a continuous process.
According to the technology, the blast furnace is loaded from above. Naturally, there were lifts.
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Lifting mechanism
Do not ask me where the remains of ancient mechanisms are, they are approximately in the same place as the remains of mechanisms from the 90s of the 20th century. And so, the furnace is loaded from above, as it is melted, molten iron, or cast iron, as it is more convenient for you, flows down the hearth, where a certain amount of it gradually accumulates, which is drained for further processing or immediately into molds.
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Blast furnace operation diagram
Depending on the volume of the hearth, the release of cast iron occurs every 2-3 hours. As the metal flows into the hearth, a new charge is charged into the blast furnace from above, and the cycle continues.
The recipe, which was found by many metallurgists at different times and in different countries, was simple and understandable: "You cannot extinguish the furnace." About the technical details, why the constant burning of the blast furnace is more profitable, how it improves the properties of the metal being smelted and why in this case less efforts of blacksmiths are required, during subsequent processing, I suggest reading about all this, friends,]]> here is a link to a good article on metallurgy]]>. In the meantime, just accept it as a fact: economically and technologically, the constant operation of the furnace is more profitable. Now let's get down to the calculations.
Our blast furnace has an inner diameter of 4 meters, the height of the working area, judging by the proportions of the furnace, is at least two meters, and possibly even more.This gives us a working area of 25,000 liters. It is easy to calculate by the formula: V = πr2h where V is the volume; π = 3.14; r is the radius of the furnace; h is the height of the working area.
For comparison, the weight of 1 liter of pure water is 1 kg. Iron ore is much heavier than water, due to its higher density, therefore 1 liter of ore weighs much more, depending on the type of ore, 2 or more times. Fuel, in our case, can be both coal and wood. Stone, is also heavier than water, but wood is lighter. But in comparison with stone, wood burns out faster, therefore, it needs to be added to the furnace more often, and accordingly, its volume increases. Also for smelting, a flux is required - limestone, which is also heavier than water.
It turns out that one load of this furnace requires 50 tons of ore and about 50 tons of coal and flux. That is, for this furnace, only for one load, raw materials, you need to bring about 100 tons. Considering that the local ore is still poorer than on the Kursk Magnetic Anomaly, we will assume that the cast iron is drained not after 2-3 hours, but after 8-12 hours, that is, only twice a day, which means the daily supply of raw materials, is 200 tons.
At the same time, the exit from the furnace of all solid materials is also a wagon and a small cart, since it is necessary to take away the resulting slag and send the finished metal for further processing.
Thus, we came to the conclusion that it is simply physically impossible to carry out all these transportation by carts, since an ordinary cart pulled by one horse can carry about 700 kg, on a more or less flat and strong road. In the case of uneven or muddy roads, it is not recommended to load the cart, more than the weight of the horse itself.
That is, to ensure the continuous operation of the furnace, only for the delivery of raw materials you need: 200 tons / 700 kg = 285.71 that is - 286 horses, 286 carts, and 286 cabmen. It seems that not a lot, considering that one of the owners of the plant, Nikolai Petrovich Khlebnikov, was engaged in breeding horses, but 286 carts of raw materials per day, this is only 5 minutes for unloading. Is it a lot or a little? I don’t know, but apparently, you really need to be an epic hero in order to throw 700 kg of stones in 5 minutes.
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Cargo cart
Well, or the carts were dump trucks. And then, how were the carts loaded in quarries and mines in 5 minutes? But that is not all.
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A string of carts
Friends, now just imagine this endless line of carts. What if one of the horses twists its leg, or the cart's axle breaks? Considering the width and quality of the roads, the question immediately arises: how did they leave on the roads?
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A string of carts
In addition, carts sometimes need repairs, horses and cabbies, need food, sleep, rest. This means that there were at least 2 times more such carts. And how much did a horse cost in the 18-19 centuries? Do not know? - take an interest, it will be interesting. But that's not all, now we have calculated only the supply of raw materials for the blast furnace itself, moreover, in good weather. And in addition, logistics includes accounting for muddy roads, dispatch of finished products, slag, delivery of tools and auxiliary cargo. Also, for the operation of a blast furnace, water is required to cool it. Plenty of water.
But that's not all. To obtain a good smelting result, it was necessary to pre-enrich the mined iron ores. The beneficiation operation has always been a very important technological condition for the production of iron. The enrichment process consists of several stages:
flushing;
drying;
burning;
crushing;
screening.
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Ball mill
Obtaining a highly concentrated ore could not be limited to only one or two operations, this process required systematic processing with all the specified methods. The local museum keeps such "cannonballs", which apparently were used to "shoot" the mills.
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Balls in the museum
As you can imagine, firing also required high-quality fuel, and in considerable quantities. Therefore, in addition to the whole industry of smelting iron ore, there was an equally large-scale industry for its enrichment. Let me remind you once again that this is not a city, but a simple village.
And now friends, I ask you, do we really have to take on faith that the logistics was organized only on horse-drawn carts? Or was there a railway? How was the operation of the blast furnace ensured in the 1700s, if officially, the first railway in Russia was built only in 1837?
Thus, the presence of metallurgy and the level of its development determines the level of development of the state. That is why, "Western partners" need to distort, deny and dispute the fact of developed metallurgy in our country in every possible way. Wherever possible, the officials are trying to prove that there was no metallurgy at all, where the fact of the presence of metallurgy is already irrefutable, its artisanal origin is explained to us, such as it was cooked in potted stoves. However, in our time, a lot of people, in their garages and in personal plots, are engaged in self-smelting of metals - aluminum, copper, and even iron. The Internet is full of videos on this topic. And what if, after 200 years, archaeologists find their homemade stoves, then they unanimously decide that the entire modern industry was so developed?
Yes, our people know how to cook metal, even in pots at home, we can say that in our blood, but this does not mean at all that there were no medium and large industrial enterprises.
High quality photos (no registration required),]]> link here]]>.
Film by article:
Friends, in the next article, the topic will be continued, and it will be about the Church of the Nativity of Christ in Istia, which is literally 300 meters from our blast furnace. And enough for today, thank you for your attention, all the best to you, goodbye!
Cast iron
Cast iron is also suitable for making a metal furnace. It is very fragile.
In terms of thermal conductivity, it is somewhat inferior to steel. But, at the same time, it has a significantly higher heat capacity. Therefore, the cast-iron stove will continue to heat the room for some time (about 3 hours) after the combustion process stops.
Cast iron metal furnaces are made from a material with a thickness of 6-25 mm. These are very heavy structures. As a rule, they are used to heat compact rooms.
Due to its low thermal conductivity, cast iron is not able to heat large spaces, but is well suited for small spaces due to its high heat capacity.
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Cast iron does not "breathe", but in terms of chemical resistance it is close to ceramics. In comparison with steel counterparts, cast iron stoves do not deteriorate with prolonged disuse.
As a rule, greenhouses, rabbitries, poultry houses and similar utility rooms are heated by means of cast-iron stoves.
Getting to know the equipment
The hearth is able not only to heat the home, but also to make it especially cozy. But old brick ovens are not effective enough, they heat only one room in which they are located and it will take several hours to warm it up.
And a completely different matter is metal samples, which within half an hour are able to heat a room with a significant area. Such a furnace can be used as a backup or additional heat source and, if necessary, can be easily dismantled and moved to another place.
A metal stove for a home belongs to long-term combustion units and can work for several hours without additional fuel consumption. It is subdivided, depending on the material of manufacture, into:
Steel
Cast iron
And depending on the purpose, they can only be heating or heating and cooking.