Arc welding, its variety and application
The history of creation, method of operation and principle of working with various metals using a welding arc were known back in the 19th century.
Russian physicist Vasily Petrov created the conditions for the functioning of a stable electric discharge (1802). Later, his welding ideas were used in practice by another of our compatriots, Nikolai Benardos. He managed to connect metal parts with an electric arc, which was created between a non-consumable carbon electrode and a product being welded by fusion (1882).
Arc welding is the basis of metal joining
Already the first welding unit provided gas supply for an efficient process where two electrodes or one electrode and the part being processed with it interacted.
Development of arc welding
The next stage in the historical development of arc welding was the experiments of the Russian engineer Nikolai Slavyanov. The non-consumable carbon electrode was replaced by a metal one, which melted and eliminated the need for a separate filler metal (1888).
These discoveries of Russian testers became the basis on which the modern production of arc welding units throughout the world is built. Everything that happened next went along the following paths:
- finding protective equipment and methods for processing metal being melted for welding;
- automation of various methods of the welding process.
Several methods of protection are currently known:
- gas,
- gas-slag,
- slag.
Welding automation, in one form or another, allows us to classify it into three main groups:
- fully automatic,
- mechanized,
- manual.
The electrical discharge used must be of the required duration. For this, a special arc power source is used (for brevity, the abbreviation IPD is used). Therefore, in the AC format, a welding transformer is used, and if the current is DC, a generator or rectifier is used.
Varieties of arc welding
Welding using coated electrodes
The entire welding process is carried out manually, by melting the surface being treated. It is assumed that consumable and non-consumable electrodes will be used. From the first group, preference is given to:
- aluminum,
- copper,
- steel
electrodes and some others, depending on the specific welding parameters. The second group is characterized by the use of:
- tungsten,
- graphite,
- coal
electrodes of various diameters.
Most often, steel electrodes are used. In this case the following is carried out:
- supplying the electrode to the area of the proposed process,
- the process of moving the welding arc along the entire length of the processed surface of the part on which a seam is formed by melting.
This method of connecting parts with an electric arc is one of the most common. It compares favorably with the others in that it is extremely simple and versatile when the welding machine is used for the manufacture of structures of various profiles. This method has proven itself to be excellent in cases where it is necessary to work:
- in a horizontal, vertical position or carry out welding work at an angle;
- in places where it can be difficult to provide normal access.
Disadvantages include:
- low productivity of this type of arc welding,
- direct dependence of labor results on the professionalism of the specialist performing this work.
Arc welding with a non-consumable electrode in argon
Welding using stick electrodes
In modern terminology, this arc welding process is called MMA. This is the English name (from Manual Metal Arc), in our tutorials and instructions the abbreviation RDS is sometimes used. With this method, electric current in a constant or alternating format is supplied to the electrode and the part to be welded.
The arc naturally melts the electrode and the surface of the part. In this case, the electrode forms separate drops of material for mixing with the melted surface of the part. The depth of penetration is adjusted by the welder and depends on what are:
- the strength of the supplied electric current,
- diameter of the electrode used,
- position (vertical, angular or horizontal) of welding,
- the speed of movement of the welding arc over the processed area of the intended seam,
- type of connection (single, double, etc.),
- shape and dimensions of the processed edge of the part
and other factors affecting the welding process.
Separately, we can consider the process of igniting and maintaining the arc, setting the necessary welding current parameters. However, in most cases, when welding, a device in the form of an inverter is used, where these functions are prescribed separately, in the attached instructions, in relation to each model and the diameter of the electrode used.
Submerged Arc Welding
This method is most often used in industrial sectors, when there is a need to weld products containing:
- various alloys,
- steel,
- non-ferrous metals,
because this way:
- highly productive
- is distinguished by excellent quality of work and stable connection of welded surfaces,
- significantly improves working conditions,
- Consumes significantly less electrical energy and materials for welding.
Submerged Arc Welding
Carbon dioxide is supposed to contain mixtures with inert/active gases to create maximum arc combustion efficiency. Experts believe that the disadvantage (and a very significant one) of this method is the limited provisions for conducting work. Since a deviation from the horizontal even by 10 degrees leads to flow of flux and metal, the welding process can only be carried out in a position from below.
This method is used in single-arc welding mode, which uses one electrode. In this case, a welding arc burns between the supplied wire (playing the role of an electrode) and the part (the surface to be welded), which is located under the flux layer. By gradual melting of the flux, a cavity is formed in the gas formed during this process (the so-called gas bubble), where the combustion of arc welding is ensured.
This type of welding is possible both in alternating current and direct current modes. Sometimes double-arc or multi-arc welding is used, and there can be one or more power supply apparatus.
Manual TIG arc welding method
This method is possible when using a non-consumable electrode in a protective inert and carbon dioxide, forming an effective mixture. The modern TIG welding method is included as one of the functions in almost all new inverter products.
Any device of the 21st century has it, in combination with other auxiliary functions. This abbreviation stands for Tungsten Inert Gas, and since the best non-melting material is tungsten, you can often find the abbreviation WIG. It stands for Wolfram Inert Gas. There is also the designation GTA, that is, Gas Tungsten Arc.
With this method, a wire is fed manually or automatically, playing the role of an electrode. In any case, one of the inert gases, most often argon, is mixed in carbon dioxide. Therefore, such welding is also called argon-arc welding (ARA). In addition to argon, the following are also used:
- all kinds of gas mixtures,
- nitrogen,
- helium,
and sometimes atomic hydrogen welding, similar to TIG welding, is used. Since the discovery of the advantages of welding in carbon dioxide and its mixtures with inert gases, this method has become widely used in industrial sectors.
In this case, arc welding by fusion of the treated surface with a non-consumable electrode can be carried out in all three of the above modes, ranging from manual mode to automatic mode.
The welding machine used allows the use of all types of electrodes, from the thinnest to the thickest.
Arc welding in MIG/MAG mode. This is welding using a consumable electrode. It is also produced in carbon dioxide with all sorts of inert/active gases:
- nitrogen,
- helium,
- oxygen,
- argon
and others.
At the same time, combining in carbon dioxide, these additional components form the most effective mixture for fully maintaining arc welding, which occurs by melting the electrode and the workpiece. This modern method also supports any welding inverter available on the Russian market. The use of various mixtures with carbon dioxide must be correlated with the specific parameters of the proposed technical specifications.
Source: http://zavarimne.ru/texnologiya/dugovaya-svarka-ee-raznoobrazie-i-primenenie/
Welding history
The historical development of welding can be traced back to ancient times. The earliest artifacts date back to the Bronze Age. The small gold boxes housed in the Irish National Museum were actually produced by pressure welding, which is known to require no heat and is produced by plastic deformation at room temperature. It is assumed that these boxes were made more than 2 thousand years ago.
During the Iron Age, the Egyptians and the eastern Mediterranean learned to weld pieces of iron together. Many of the tools that have been found were made during the period around 1000 BC.
In the Middle Ages, the art of blacksmithing reached its dawn and many products that appeared at that time were welded by forging, until welding as we know it today was invented in the 19th century.
1800 g
It is believed that acetylene was discovered by the Englishman Edmund Davis. But the first to obtain an arc discharge was another English chemist, one of the founders of electrochemistry, an honorary member of many scientific organizations, including the St. Petersburg Academy of Sciences, Sir Humphry Davy. He received an arc electric discharge between two graphite rods, which were connected to the poles of an electric battery composed of 2 thousand galvanic cells.
Since the mid-19th century, the electric generator has been invented, and lighting using an arc discharge has been gaining popularity. And by the end of the 19th century, gas welding and cutting, arc welding with carbon and steel rods, and electrical resistance welding appeared.
1880
Auguste de Meritan, conducting research in the Cabot laboratory in France in 1881, used the heat of an electric arc to fuse the lead plates of rechargeable batteries. At that time, his student was the young Russian scientist Nikolai Nikolaevich Benardos, who worked with de Meritan in a laboratory in France and became, in fact, the father of welding.
The patent for the “Electrohephaestus” electric arc welding method was awarded to Nikolai Benardos and Stanislav Olshevsky. The British patent was issued in 1885 and the American patent in 1887. Bernados also developed the first electrode holder and so on. And although welding with a graphite rod was limited in its capabilities, already in those days it was possible to weld iron and lead.
The method began to be widely introduced at the end of 1890 - beginning of 1900.
1890
N.G. Slavyanov presented his version of the idea of metal transfer through an arc (through a steel rod), and also adapted this method for casting into a mold and received a Russian patent for the method of electric steel casting.
At the same time, in 1890, the founder of General Electric, C.A. Coffin of Detroit patented in the United States exactly the same process of electric arc welding with a steel rod that was melted by the force of the arc, followed by metal transfer into the weld pool and crystallization of the weld.
1900 g
Around 1900 A.P. Strohmenger, whose name is unknown in the post-Soviet space, introduced in the UK the first steel electrode with a thin coating of clay or lime, which stabilized the arc.
But the electrode with flux coating was invented by the Swede Oscar Kjellberg, who was at the origins of the ESAB company. Work on the creation of coating was carried out from 1907-1914. Piece electrodes were made by drawing and cutting solid metal wire into rods, followed by immersion in solutions of carbonates and silicates. After drying, they were ready for sale.
At the same time, British engineer Elihu Thomson invented resistance welding.
In 1903, the German Goldschmidt (literally “goldsmith”) invented thermite welding, which was used to connect railway rails.
Gas welding and cutting also developed during this time. The production of oxygen, and later the liquefaction of air, along with the invention of the gas burner, contributed to this. Before 1900, attempts were made to weld in an oxygen-hydrogen flame, with the mixture contained in one cylinder.
The blowback could lead to a powerful explosion, so the chemist Sainte-Clair Devilleme decided to separate the gases and mix them in a burner. The process became safer, but at the exit St. Clair received a low-temperature torch of 2200 degrees. And only in 1901
The French Edmond Fouché and Charles Picard invented an oxygen-acetylene burner, the drawings and characteristics of which have not changed significantly to this day.
The First World War triggered the militarization of factories and a “golden age” began for welding. Welding machines and electrodes for them began to be mass produced.
1920 - present
In the 20s, different types of welding electrodes were developed, recipes for new fluxing coatings were compiled, and discussions were ongoing on the methodology for their production. The introduction of metal marking required the creation of a classification of coatings and the steel electrode rods used. It was necessary to create more reliable welding seams.
In the 20s, the influence of shielding gases on the welding process was thoroughly studied, since O2 and N2 of air in contact with the liquid metal of the weld caused porosity and hot brittleness. Various gases were supplied to the welding zone, then everything was carefully analyzed.
American chemist Irving Langmuir conducted experimental work with hydrogen as a protective welding atmosphere. He placed two electrodes next to each other, first made of graphite, later made of tungsten. A voltaic arc was ignited between them in a hydrogen atmosphere and active splitting of hydrogen molecules into atoms was observed.
The temperature of the dissociated flame was ~ 3700 ° C, which is sufficient for welding, and the high activity of hydrogen provided excellent protection of the weld metal from damage caused by O2 and N2 air.
The process is called atomic-hydrogen welding, but is not widely used and is used primarily for tool steels.
Similar work was also carried out by the Americans HM Hobart and PK Devers, only they worked with argon and helium. The result of the empirical research of these gentlemen was a patent for electric arc welding in a gas environment, which can be considered the first step in the creation of a modern inverter argon arc welding machine, which appeared, however, much later.
The patented process was ideal for welding Mg, Al, and Cr alloyed steel and was perfected in 1941. The technology was called inert gas tungsten arc welding. Today it is used both in production and at home. ArDS devices are most often used.
Among other things, equipment was developed for working in an environment of inert/active gases with a consumable electrode, which is a welding wire passing through a feeder to the burner nozzle along a flexible hose.
1928
In 1928 in the Soviet Union D.A. Dulchevsky invented automatic submerged arc welding. The development of the process began in the late 30s thanks to the efforts of scientists at the Institute of Electric Welding of the Academy of Sciences of the Ukrainian SSR under the leadership of Academician E.O. Paton, which played a big role in tank building, the production of guns and aircraft bombs during the Second World War. Submerged arc welding has found wide application in all sectors of the national economy. This is an effective way to obtain strong seams with good efficiency.
In the USA, the automatic welding process is called “powder submerged arc welding”. It was patented in 1930 by a certain Robinoff, and then sold it to Linde Air Products Company. In 1938, submerged arc welding was actively used in shipyards and ordnance factories.
In 1930, the curious Stud welding process was developed for the New York Navy Yard. Stud was used to secure wooden decking over a metal surface. Stud welding has become in demand in the shipbuilding and construction industries.
In 1949, electroslag welding was born at the Paton Institute in Kyiv, which removed restrictions on the welding of large-sized products. Now you can cook any thickness! The process was presented to the world public at the Brussels World Exhibition in Belgium in 1958
In 1953, K.V. Lyubavsky and N.M. Novozhilov invented a very economical method of welding with a consumable electrode in a CO2 environment. The new method gained worldwide recognition, as it made it possible to work on conventional inert gas welding equipment.
In 1957, the electron beam welding process was discovered by the French Atomic Energy Commissariat and found application in the automotive and aviation industries.
In 1957, Robert F. Gage invented the plasma arc welding process. The temperature in plasma is about 30,000°C, in contrast to an electric arc, the temperature of which is no more than 5000–7000°C.
1960
The use of gas mixtures begins, which consists of adding a small amount of oxygen to an inert gas. In general, the use of mixtures for various steels gives positive results. Pulsed current welding is being introduced.
Soon after the invention of the popular method of semi-automatic welding in carbon dioxide (CO2) by Soviet scientists, it was invented to use a consumable wire electrode with a flux core. When melted, the fluxing powder provided additional gas protection from the inside; carbon dioxide protection was used from the outside.
In 1959, a wire electrode was invented that did not require external gas protection. Now it is known as “self-protecting flux-cored wire”; it is most often purchased for cases when it is impossible to use gas. With this wire there is no need to carry a gas cylinder back and forth.
And for a snack
Friction welding was invented in the Soviet Union. The principle at work here is the conversion of mechanical energy into thermal energy due to the frictional forces that arise when connecting two parts with a certain compression force.
Laser welding is an innovative welding process. The laser was originally developed at Bell Telephone Laboratories as a communications device. But thanks to its ability to concentrate huge amounts of energy in a small volume, it also turned out to be a powerful source of heat, which is used today for highly efficient welding and cutting of metal.
Source: http://svarka-master.ru/istoriya-svarki/
Who invented carbon electrode welding?
The historical development of welding can be traced back to ancient times. The earliest artifacts date back to the Bronze Age. The small gold boxes housed in the Irish National Museum were actually produced by pressure welding, which is known to require no heat and is produced by plastic deformation at room temperature. It is assumed that these boxes were made more than 2 thousand years ago.
During the Iron Age, the Egyptians and the eastern Mediterranean learned to weld pieces of iron together. Many of the tools that have been found were made during the period around 1000 BC.
In the Middle Ages, the art of blacksmithing reached its dawn and many products that appeared at that time were welded by forging, until welding as we know it today was invented in the 19th century.
Electric welding
February 13, 2015.
Category: Electrical engineering.
There are two types of electric welding: 1) arc and 2) electric resistance welding.
Arc welding
Electric arc welding was invented by the Russian engineer N. N. Benardosn in 1882.
Nikolai Nikolaevich Benardos (1842 – 1905), in addition to electric welding and soldering of metals, invented a method for electrolytically coating the hulls of iron ships with copper. N.N. Benardos is the designer of a combined gas-electric soldering iron. He was the first to use an electric arc to cut metals under water. N. N. Benardos received the title of honorary electrical engineer.
Electric arc welding uses the heat generated by an electric arc. When welding using the Benardos method, one pole of the voltage source is connected to a carbon rod, and the other pole is connected to the parts that need to be welded (Figure 1). A thin metal rod is inserted into the flame of an electric arc, which melts, and drops of molten metal, flowing down onto the parts and solidifying, form a welding seam.
Figure 1. Electric welding using the Benardos method (with a carbon electrode)
In 1891, Russian engineer N. G. Slavyanov proposed another method of electric arc welding, which became most widespread. Nikolai Gavrilovich Slavyanov (1854 - 1897) worked at the Votkinsk plant and in Motovilikha (near the city of Perm). In 1893, at the World Exhibition, N. G. Slavyanov received a gold medal for the method of electric welding under a layer of crushed glass (flux).
Electric welding according to the Slavyanov method is as follows. The carbon rod is replaced by a metal electrode (Figure 2). The electrode itself melts, and the molten metal, solidifying, connects the parts to be welded. When the electrode is used, it is replaced with a new one.
Figure 2. Electric welding according to the Slavyanov method (with a metal electrode)
Before welding a part, it must be thoroughly cleaned of rust, scale, oil, and dirt using a chisel, file, or sandpaper.
Figure 3. An example of a weld resulting from the use of electric arc welding
To create a stable arc and obtain a durable seam, metal electrodes are coated with special compounds. Such coating also melts during operation during melting of the electrode and, filling the highly heated surfaces of the parts being welded, prevents them from oxidizing.
Time-lapse footage of arc welding in action:
Electric resistance welding
If you put two pieces of metal close together and pass a strong electric current through them, then due to the release of heat at the point of contact of the pieces (due to the high transition resistance), the latter will warm up to a high temperature and weld.
Figure 4. Contact electric welding
Currently, electric welding, both arc and resistance welding, has firmly entered the industry and has become very widespread. They weld sheet and angle steel, beams and rails, masts and pipes, trusses and boilers, ships, and so on. Welding is used to perform new and repair old parts made of steel, cast iron and non-ferrous metals.
electric welding by resistance method:
Scientists and inventors in our country have developed many new methods of using electric welding. Professor K.K. Khrenov proposed a method of underwater electric welding, which was widely used in the construction of the Saratov-Moscow gas pipeline. Automatic welding, proposed by Academician E.O. Paton, allows you to weld metals very quickly and with high quality in mass production. Academician V.
P. Nikitin designed a welding machine that allows welding using the now most common alternating current. The device has a special part - an oscillator, the purpose of which is to generate alternating current of high voltage and very high frequency, which ensures stable arc burning when welding thin and thick metal parts.
When electrical circuits are closed and opened by a switch or circuit breaker, as well as contacts of devices and devices are closed and opened, an electric spark that occurs between the contacts, and often the following electric arc, melts the metal, and the contacts burn or weld, disrupting the operation of the installation. This phenomenon is called electrical erosion (from the Latin word “erogo” - “gnaw out”). When a spark appears, it seems to “gnaw” the metal. To combat a spark, sometimes a capacitor of a certain capacity is connected between the contacts parallel to the spark gap.
Engineers B. R. Lazarenko and I. N. Lazarenko used the property of an electric spark to “gnaw metal” in the electrical erosion installation they designed. The operation of the installation is basically as follows. One wire from a voltage source is connected to the metal rod.
Another wire is connected to the workpiece, which is in oil. The metal rod is made to vibrate.
An electric spark that occurs between the rod and the part “gnaws” the part, making a hole in it that is the same as the cross-sectional shape of the rod (hexagonal, square, triangular, and so on).
Source: https://www.electromechanics.ru/electrical-engineering/619-electric-welding.html
Who invented welding
The history of the development of welding goes back to our era. Ever since people learned how to mine metal, they have strived to create something useful from it. The most reliable connection method is the hot method. Now it is difficult to imagine that two centuries ago Russian scientists stood at the origins of modern welding machines.
Since then, a new page in the life of humanity began. Now there are several types of welding technologies used in production and at home. The modern history of welding is the invention of new units, methods of joining metals, and personal protective equipment of a new generation. But the traditional arc method using molten and refractory electrodes remains popular. Welders create huge metal structures and miniature works of art.
The role of welding in the modern world
Laser welding methods are currently being developed. A technology for high-precision metal joining has been developed. New composite materials are appearing; the use of aluminum, stainless steels, and non-ferrous metals is widespread. The following types of high-temperature metal compounds are widely used:
- argon-arc technology makes it possible to obtain all types of connections: butt, corner, T-joint, overlap;
- gas, with its help, main pipelines are created that run far from power sources;
- semi-automatic allows you to speed up the process of joining elements, has high accuracy, and reduces the risk of a poor-quality seam;
- Traditional manual electric arc always remains in demand.
Power sources are changing, holders are being improved, but the principle of hot joining of metals does not change. The welding method is preferable to other types of connections due to a number of advantages:
- due to saving metal;
- wear-resistant equipment has a large margin of safety and is used in any conditions;
- compounds are formed at the molecular level with high strength.
First mentions of welding
Long before the advent of welding units, there were other ways to join metal. Samples of compounds created in the 8th – 7th centuries BC have been found. Native gold, pieces of copper and meteorite alloys were used for household purposes and weapons. They were held together by heating using a method comparable to forging.
Source: https://svarkaprosto.ru/tehnologii/kto-izobrel-svarku
Manual arc welding - video and operating principle of the welding machine for beginners
The RDS method is the most common and accessible method of welding with a coated electrode. The instructions for manual arc welding video clearly show that this method is mobile and easy to use, and does not require any additional equipment. To get acquainted with welding techniques and learn everything about the “manual arc welding” method, watch the video on our website.
The essence of the RDS process
The essence of manual arc welding is that the metal being welded is melted by the heat of the arc, and the ignition, maintenance and movement of the arc is carried out manually. One of the elements is a metal rod, and the other is the product to be welded.
With the help of a current source (alternating or direct), a welding arc is formed at the tip of the electrode, which melts the electrode itself and the product, forming a liquid weld pool, from which a future seam is then formed as it cools.
The seam is then covered with a slag crust, which is beaten off with a hammer after welding is completed. Sometimes welds require additional processing or cleaning.
After watching various video instructions for beginners, arc welding will become a clear process.
This method is suitable for welding carbon, low alloy, structural, high alloy, heat resistant steels. It can also be used to cut and weld metal. Using special electrodes, it is possible to weld non-ferrous metals.
As you can see in the video, electric arc welding of cast iron or stainless steel is carried out using direct current, and aluminum - using alternating current.
Types and methods of RDS
There are the following methods and types of manual arc welding: welding “with the coating supported” (gives a greater depth of penetration), “beam” welding (increases productivity), welding “tub” method (allows you to save energy and reduces costs, used for welding reinforcement bars) , welding with a “three-phase” arc (the stability of the arc is ensured), as well as welding with an “inclined” or “lying” electrode (serves to mechanize the process).
Welding machines, types and principle of operation
Information for beginners will be useful: arc welding can be carried out using completely different equipment: transformer sources, rectifiers, inverters.
Any welding machine is, first of all, a source of welding current, which is necessary to obtain and maintain a welding arc. The operating principle of the welding machine is as follows.
Its housing contains a power transformer that converts the current from the socket (AC) with high voltage into welding current (AC or DC) with a reduced safe voltage. With the help of a transformer, the current is also adjusted and the required current-voltage characteristic is formed.
The welding machine is connected to a socket (primary current), and depending on the voltage (220/380 V), a welding cable is connected to the secondary current in the connectors on the front panel of the machine using current tips. The type of source used will determine what welding current will be output from the machine. It can be variable or constant.
The operating principle of a DC welding machine is based on the conversion of alternating current from the network, but, thanks to the rectifier unit in the design of such devices, the current is rectified and becomes constant.
Next, an electrode holder and a grounding terminal (or a mass clamp on the product) are connected to the cable. When welding with direct current, the amount of heat on the electrodes is different, therefore the concept of polarity was introduced in welding. As shown in the video, electric arc welding can be performed with direct or reverse polarity.
The electrode holder can be connected to both the “positive” connector (reverse polarity) and the “negative” connector (straight polarity). Which polarity to choose when welding depends on the thickness of the product and the brand of electrodes used. The classic connection method is “plus” on the holder. The mass clamp is securely attached to the product or workpieces.
The method of attaching a mass clamp to a welding table is also quite common. The welding current is set before starting welding using a special regulator, and its value depends on the thickness of the metal that will have to be welded and on the selected electrode diameter. The power of the holder, grounding terminals, as well as the thickness of the welding cable are selected depending on the value of the welding current.
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Source: https://swarka-rezka.ru/ruchnaya-dugovaya-svarka-video-i-princip/
History of welding development. Scientists and their discoveries in the field of welding
The history of the emergence of any modern technology cannot be considered in isolation from generally known historical processes and generally accepted names of historical periods. Any technology initially has prerequisites for its emergence, a process of development through the prism of history, culminating, significant names of scientists, a result in modern times and prospects for further development.
The welding process, no matter how modern it may seem at first glance, appeared around the 8th-7th century BC. To create more and more advanced tools, people began to change the shape of metal, which existed on its own in nature, and also tried to connect small pieces of it. These metals included copper or gold. They did this only with the help of stones and physical strength. This process was the first type of cold welding.
A little later, man learned to independently mine other types of metals (copper, lead, bronze), and also to produce larger products using heat treatment - heating individual elements. Casting was already used to produce almost perfect products.
The Iron Age is characterized by the fact that people learned to mine iron. This mark appeared on the time ruler about three thousand years ago. The process of iron mining now looks very simple: iron is separated from natural iron ores by smelting. But in ancient times it looked different, since no one knew how to melt.
A certain mixture with only iron particles was obtained from iron ore. In addition, this mixture contained non-metallic impurities: coal, slag, etc. Only after a significant amount of time, by forging the heated mixture, was it possible to separate the iron from everything else.
The result was iron blanks, which were subsequently forged welded into amazing products: tools and weapons.
The most advanced technologies in the welding process until the Industrial Revolution were only forge welding and brazing. The latter was widely used in the field of jewelry production.
Fundamental discoveries
A breakthrough in welding technology was made during the industrial revolution or industrial revolution. Discoveries in the field of electricity were made over the centuries, which ultimately led to the following.
In 1802, the Russian physicist Vasily Vladimirovich Petrov discovered and, as an experimental physicist, proved the possibility of using the electric arc in practice. This discovery is considered the most outstanding success of the scientist. It is the main prototype of modern welding devices. He outlined all the conclusions of his discovery in the book “News of Galvanic-Volt Experiments,” published in 1803. However, at the time of its opening, no one was particularly interested in it.
V.V. Petrov. Russian experimental physicist, academician of the St. Petersburg Academy of Sciences, inventor of the electric arc
Sir Humphry Davy conducted research with the electric arc in 1821. His student, Michael Faraday, devoted a lot of time to studying the connection between electricity and magnetism. In the 1830s he discovered electromagnetic induction.
A little later, the electric arc began to serve for the benefit of society when it appeared in household lighting lamps.
Only in 1881, Nikolai Nikolaevich Benardos, a Russian engineer and inventor, came up with the electric arc welding “Electrogefest”. After several years of improving the invention, in 1887, it was patented, and a few years later it spread not only throughout Russia, but throughout the world.
Postage stamp with the image of N.N. Benardos in honor of the 100th anniversary of the invention of electric welding
In 1885, Bernados opened the Electrogefest partnership, which had the first welding workshop. Benardos received a patent for his invention for the first time. The scientist spent his last savings on obtaining this patent in Russia; European countries issued the patent with the help of funds raised from the merchant Olshevsky.
After the worldwide spread of the electric arc welding method and worldwide recognition, Benardos developed electric arc welding with carbon and metal electrodes. He became the founder of the idea of the electric arc welding process with a metal electrode using alternating current; inclined electrode welding; technicalization of the welding process.
Thus, all of the above scientists and inventors are considered the founders of welding, those who invented it.
Despite such key discoveries in the field of electric welding, the 14th century is not famous for its extensive and widespread use, since electricity was in short supply. It was problematic to apply all the new discoveries, but no one was going to refuse to use them. The transformation of welding equipment and welding machines continued.
The year 1904 was marked by the appearance of cutters. The years 1908-1909 are characterized by the emergence of underwater metal cutting technology. It began to be used in France and Germany.
Gas welding occupied a leading position in welding production until the 30s, and was intensively used during the First World War. The Baku-Batumi and Grozny-Tuapse main pipelines were built using gas welding.
The construction of pipelines was carried out using only gas and gas press welding processes.
Construction of the Baku-Batumi oil pipeline
Electric arc welding was not so widespread in those years due to the fact that its power source required improvement (the length of the arc was short and it burned unstably). This problem was addressed in the period from 1914 to 1917. allowed by such scientists as Stromenger, S. Jones, Andrus and Stresau, each of whom contributed to the creation of a coating for the welding electrode to make it easier to maintain the arc.
Modernity
Let us briefly outline the types of modern welding process.
Electric arc welding.
Currently it occupies a leading position among other species. Today it is the most common, accessible and cheap.
Electroslag welding.
The most advanced process in the field of welding large parts, such as ship construction, load-bearing structures, boilers, rails, etc. The fundamental principle of this type of welding is that an electric current is passed through the slag. Slag is formed when flux melts, and it is also a conductor of electric current. As an electric current passes through the slag, heat is released.
There are the following types of electroslag welding:
- three electrode wires;
- large cross-section electrodes.
The essence of electroslag welding
Contact and press welding.
Resistance welding is the oldest. Founder: William Thompson. Initially it was distributed in the USA, after which it began to be used in Russia. This was accompanied by an increase in the volume of research activities in this area in Russia: factories and combines “Orgametal” (TsNIITMASH), “Electric”, “Institute of Electric Welding named after. E.O. Paton", Moscow Higher Technical University named after. Bauman, VNIIESO and others.
Contact welding is divided into:
- Butt (connecting parts along the entire plane of their contact by heating);
- Point (parts are connected at one or several points simultaneously);
- Relief (elements are connected at one/several points with special protrusions-reliefs);
- Suture (connecting elements with a seam).
contact welding
Pressure welding or pressure welding is the joining of metals without melting them (solid surfaces), only with deformation using force. This type of welding came to us straight from antiquity with its cold welding.
Gas welding and cutting.
Gas welding is a process of melting metal using special torches in which flammable gases are burned. The first gas burner was invented in France at the end of the 19th century. It worked on a mixture of oxygen and hydrogen.
When cutting metal, it occurs by “burning” the metal in a stream of oxygen.
Beam types of welding.
Modern research by scientists in the field of optics and quantum mechanics makes it possible to identify completely new types of beam welding based on the energy of ion and photon rays. The following types of beam welding are distinguished:
- Electron beam (heat source is an electron beam; the welding process takes place in a special installation: in vacuum chambers);
- Laser (heat source – laser beam). This type is distinguished by the following features: environmental safety, lack of mechanical processing, high welding speed, and the significant cost of laser systems.
Laser welding
- Plasma welding (heat source is a plasma jet, that is, an arc produced using a plasma torch). The plasma torch can be of direct or indirect action.
Prospects for the development of the welding process
Prospects for the development of welding production arise from the current disadvantages or problems of existing and used types of welding. Today, the most experienced scientists and equipment developers are working hard on any shortcoming to make human life and production even easier.
The first thing that improvement is aimed at is the creation of welding machines that are fully or partially automatic. In the future, such a move will increase the efficiency of the welding process and increase the power factor.
The second is the ability to remotely control and regulate the welding process of large-sized and complex elements of a single structure (highways, industrial facilities, etc.)
Third, finding a way to reduce the cost of laser welding, as was once done with electric arc welding.
Another problem is the fact of creating high-quality and durable welded structures that are capable of functioning not only in normal conditions, but also in conditions of sharp temperature changes, under water and even in outer space, which is very important today.
Currently, the welding process as a whole is being computerized. Computerization refers to the introduction of computer technology capabilities into the main areas of engineering activity in the field of welding: scientific research, preliminary design, management and control of technological processes.
It is important not to overlook the importance of information in welding. Having the right information, at the right time and in the right place, only increases the opportunity to make truly important discoveries. Information must be accessible, open and understandable. This requires unified systems and databases with the necessary reference and bibliographic information for all interested parties.
It is obvious that welding is a unique process that has no analogues. The beginning of development occurred before our era, and this process has not stopped to this day. Given the need for this unique technology, a number of scientific studies are being conducted. It can be said with certainty that the process of development of new types of welding will not be long in coming, since technology in our time is improving at an incredible speed.
Source: https://svarkaed.ru/svarka/poleznaya-informatsiya/istoriya-razvitiya-svarki-uchenye-i-ih-otkrytiya-v-oblasti-svarki.html
