Who invented welding and when?

The history of the welding inverter - CUGP Construction portal

27.2.2017

Today, welding devices are the most popular and convenient devices for welding; many craftsmen do not want to hear about anything else. They compare favorably with their competitors, transformer devices, in size, weight and versatility. With their help, you can work with seams of any complexity, for almost any thickness, using a wide variety of principles, including the so-called “plasma welding”.

Even 60-80 years ago, such efficiency in one device would have been truly fabulous; many states would have given a lot to own such a unit, but now it can be bought in most hardware stores and supermarkets, in the Alcest online store chain.

First welding equipment

            Here it is important to remember that the principle of electric heating of metal and forging was tried by the famous scientist E. Thompson in 1905. And although it was more like blacksmithing, the main practice of working with metal at that time, Thompson's experiments became the “first sign” for the development of an entire category of tools.

            In 1907, Lincoln Electronic and CC Elektrick released the first variable voltage generators and motor generators. However, it was not until 1927 that truly applicable results emerged. Thanks to V.P. Nikitin, who achieved high-quality regulation of current for welding, patented a single-case transformer for arc welding.

First inverters

            In the early 60s of the 20th century, semiconductor electrical devices became widely used. It was at that time that the first pulse converter for welding was invented, essentially the first welding inverter.

The real breakthrough that made such devices applicable occurred closer to the 90s, with the introduction of ferromagnetic alloys and the ability to operate at ultra-high frequencies. Already in the 21st century, thanks to the widespread use of IGBT transistors, inverters have become even smaller and also significantly cheaper.

Of course, even now you can find expensive “smart” machines that use a microprocessor to control parameters and fully automatic operation. But this is, as they say, out of necessity.

Source: https://cugp.com.ua/istoriya-vozniknoveniya-svarochnogo-invertora/

Metal welding, a little history

The best way to join metals today is welding. Welding appeared in ancient times. In earlier times, various types of processing and joining of metals were used. However, they have almost never been used to create overly complex structures. For example, the ancients knew how to connect parts of metal products by soldering and welding. Egyptian pyramids contain gold parts with joints soldered using tin.

In the days before electric welding, forging was often used to weld lead pipes and lead roofing sheets. Then they heated it with charcoal. This type of forge welding was performed with hammer blows. Repair welding, which restored carriage axles, was also very popular in those days.

Invention of electric welding

At the end of the 19th century, thanks to the efforts of the Russian engineer N. G. Slavyanov, arc welding was invented. It was he who came up with a method for connecting materials using a consumable electrode made of metal. This method is now used most often. Slavyanov trained a whole team of welders, they corrected casting defects using arc welding, put steam mechanisms and other large equipment in order.

Technology development

In addition, Slavyanov created a welding generator, as well as an automatic regulator that determines the length of the arc. He developed fluxes that dramatically improve the quality of the weld. The joining technologies created by this scientist became the basis for current methods of electric welding of metal.

In the twentieth century, the famous bridge builder Academician Paton, who foresaw that electric welding would have a glorious future, dramatically changed the field of his scientific research. He created a laboratory in Kyiv in 1929, and later the first research institute of electric welding.

He developed and proposed many effective technological methods of electric welding.

Modern approach

Today's welding has received its greatest development thanks to the work of scientists, innovators and talented engineers working in this field. They created many types of equipment, different brands of electrodes.

In addition, they have developed modern welding technologies, which also include automated methods.

By the middle of the last century, a technique for obtaining permanent connections of many metals had been mastered, and the theory of manual welding technology had been developed in great detail and fundamentally.

Source: https://elsvarkin.ru/svarka-metalla/

History of welding: major discoveries, past and modern methods, future of the industry

Every social process or emerging technology is not a sudden idea. Every event is natural. Everything happens at the moment when the conditions are right for it.

It is not for nothing that many historical periods are named after discoveries, tools and the level of human development of that time. All red processes are connected by a red thread to the past and the future.

Our present depends on what happened yesterday and what to expect tomorrow. And the welding process is no exception.

A little background

Welding begins its history back in the distant 8-7 centuries BC. This is now the technology of our era - modern and convenient for everyone. Things were different in those days. Metal that existed in nature had to be processed for domestic purposes.

Its shape changed due to two things - the physical strength of man and the action of the stone. Gold and copper were most often used - these were the most common metals 2-3 thousand years ago.

They had to be processed to create other tools, as well as jewelry and utensils. This process is considered the beginning of the history of cold welding.

Over time, humanity has improved its skills, including labor ones. Independent mining of lead, bronze and copper took place.

For the manufacture of large-sized products, heat treatment technology was used. Individual elements were heated and deformed. When it was necessary to create a perfect product, they turned to the casting method.

Almost 3000 years ago there was an era of the Iron Age. It’s easy to guess from the name that people learned to mine iron at this time.

And if now this process looks simple and logical, then in ancient times people’s skills were meager, and no one knew about modern technologies.

Today, iron is obtained from natural iron ores by separating the iron from them through smelting. At that time, no one knew about this method, and there were no tools.

A certain mixture was obtained from the raw materials, which contained iron particles. Of course, it was not a pure product, and it was many times different from what we have now. It contained an admixture of non-metals - slag and coal.

After a thousand years, it was possible to obtain pure iron without any additives. This was achieved using heated metal forging technology. Forge welding made it possible to obtain very beautiful and practical products, such as weapons and tools for work.

Before the Great Industrial Revolution, craftsmen were only able to work with soldering and forge welding - more advanced processing methods were unknown. Jewelry production developed thanks to soldering.

Major discoveries

The Industrial Revolution is a real breakthrough in the field of welding. It was truly a revolution in welding and its stages. Discoveries in the field of electricity played a major role in the whole process.

1802 Russian theoretical and practical physicist Vasily Petrov made a phenomenal discovery. He proved that an electric arc can be used in metal work. This idea was not immediately perceived by scientists as something unusual.

Although decades later his merits were appreciated. Petrov created a basic prototype of a modern welding machine. He wrote about this in “News on Galvani-Volt Experiments.” The book was published in 1803.

The next stage of history is the discovery of electromagnetic induction. It is a joint effort between Sir Humphry Davy and Michael Faraday, which was born in the 1830s. Faraday drew scientific conclusions about the success of the arch by studying magnetism and electricity.

20 years later, the electric arc appears in household lighting fixtures, which proved the importance of the scientist’s discoveries for the entire society.

1881 meant the appearance of the Electrohephaestus device, which was considered the first electric arc welding. After 6 years, Nikolai Benardos, a Russian engineer-inventor, patented his device after conducting a series of experiments.

Within 5 years, the whole world knew about this device - from America to Asia.

The opening of a partnership of the same name in 1885 by the same scientist meant the appearance of the first welding workshop.

Nikolai managed to obtain a patent for his device. To fulfill his plans, the scientist spent all his savings. The merchant Olshevsky helped the discoverer pay the missing funds.

After electric arc welding was recognized in dozens of countries, Benardos began developing welding with metal and coal electrodes. He is the founder of such discoveries:

• electric arc process with a metal electrode at alternating current;
• technicalization of the process and its stages;
• welding using the inclined electrode method.

The scientists we have already talked about are considered the founders of modern welding processes. They made a huge contribution to ensuring that today's craftsmen work quickly enough.

These were key events related to welding and its development. But for the next 50 years there was a serious shortage of electricity, so electric welding was not so popular.

And although we had to temporarily forget about the new discoveries, everyone remembered that it was necessary to use electricity in welding work. It's only a matter of time. There have been some transformations in welding equipment and devices in general.

1904 Cutters appear that can be used skillfully.

1908-1909 – the time of the emergence of underwater metalworking technology. It was actively used in German and French production.

For the next 20 years, gas welding was the technology leader. It was actively used during the First World War.

Welders of that time resorted to its mechanisms when they were engaged in the construction of famous structures. The main pipelines “Grozny-Tuapse” and from Baku to Batumi are the merit of gas welding and all its processes.

At this time, electric arc welding was not popular. Everything was explained by the fact that the technology needed to be improved, because the arch burned with interference.

Andrus, Stresau, Stromengenr and others worked on this issue during 1914-1917. They came to a discovery in the form of a welding electrode. The latter did an excellent job of uniformly burning the arc.

Our years

At the end of the 20th and beginning of the 21st centuries, the development of welding did not stop.

Today, there are dozens of metalworking methods, each of which boasts its own advantages. Let's talk about each of them.

Arc welding

It is so common that it is used in 8 cases out of 10. This is a real leader who stands out noticeably among the rest.

Electroslag technology

A new way of processing large structures such as rolled metal, boilers and others. The basic principle of welding is this: an electrical impulse passes through the slag.

The latter appears during the melting of flux, which is considered a conductor of electricity. As a result, after current passes through the residue, heat is released.

There are the following types of welding using slag:

• operation of electrodes operating with a large cross-section;
• three mesh wires.

Tie and press welding

William Thompson invented the cohesive welding method, which today is considered a fairly old method. Initially it was popular in the States, then it became part of Russian technology.

In this regard, a large number of historically famous scientific centers and factories were opened, such as Elektrik, the Paton Institute and dozens of others.

If we touch on the basics, then there is such a division of the connected process:

• butt - occurs due to the combination of structures on the surface of their contact. The method of cheating parts was used;
• point - carried out by connecting parts simultaneously at a single or pair of points;
• suture – several elements are connected using sutures.

Press welding is also called pressure welding. It is characterized by fastening structures without melting it.

There needs to be a distortion in the use of force. This process at the initial stage arose even before our era, when welding without heating developed.

Gas cutting machine

This process occurs by melting metal through burners. Their task is to burn flammable gases.

For the first time in history, a gas burner was used in one of the French cities in the last decade of the 19th century. Its work is based on the fusion of hydrogen with oxygen.

When a metal is cut, it seems to burn in a stream of nitrogen.

Beam welding

The work of ion and photon flows gave impetus to the development of new types of welding. They were studied by scientists specializing in quantum mechanics and optics.

There are the following types of beam metalworking:

Source: https://prosvarku.info/tehnika-svarki/ob-istorii-razvitiya-svarki

History of the origin and development of welding

The history of the development of welding can be traced back to ancient times. The earliest examples of bonded metal are ancient bronzes. It is estimated that some items were made more than 2,000 years ago.

During the Iron Age, the Egyptians and people in the eastern Mediterranean learned to weld pieces of iron together. Many instruments have been found that were made around 1000 BC. e.

In the Middle Ages, the art of blacksmithing developed; many iron products were produced, connected by the process of obtaining permanent joints with a hammer. The history of welding suggests that until the 19th century, the joining process as we know it today using gas or electricity was not used.

The first semblance of electric welding

The production of an arc between two carbon electrodes using a battery is credited to Sir Humphry Davy in 1800. In the mid-19th century, the electric generator was invented and arc lighting became popular. For the first time, the idea of ​​the arc lighting process was developed by Professor V.V. Petrov was used for welding metals. The invention of combining metals using gases did not stop either. Edmund Davy of England is credited with the discovery of acetylene (the reaction of potassium carbide with water) in 1836.

19th century French electrical engineer Auguste de Meritan used the heat of an arc to join lead plates for storage batteries while working in a laboratory in 1881.

His student, Russian engineer Nikolai Nikolaevich Benardos, working in the same French laboratory, made his contribution to the history of the development of welding by receiving a patent for the invention of this compound. Together with the Russian engineer Stanislav Olszewski, he also received a British patent in 1885 and an American patent in 1887.

The patents also included an electrode holder. This was the beginning of carbon arc welding. Carbon arc jointing became popular in the late 1890s and early 1900s.

The history of the development of welding marks the inventor of electric arc welding as the Russian engineer Nikolai Nikolaevich Berandos (1842-1905).

In 1882, Russian engineer N.N. Benardos introduced a new method into the history of welding development, in which carbon electrodes were used.

Application of electrodes

In 1888, Russian engineer Nikolai Gavrilovich Slavyanov first used electrodes, the design of which included a metal rod under a layer of flux. In the presence of a state commission, he managed to weld the crankshaft of a steam engine.

This idea of ​​electrode coating evolved. Engineers proposed a thin coating of clay or lime that would provide a more stable arc. Oskar Kjellberg from Sweden invented a coated electrode with a mixture of carbonates and silicates.

Meanwhile, welding processes have evolved to include spot, seam, projection and butt welding. In 1903, a German named Goldschmidt invented thermite welding, which was first used to join railroad rails.

Gas cutting was also improved during this period. The production of oxygen and then the liquefaction of air, along with the introduction of the blow tube or burner in 1887, helped develop this field. However, around 1900 a burner suitable for use with low pressure acetylene was developed.

The First World War brought a huge demand for the production of weapons and the history of the development of welding was in demand for the production of weapons. Many companies have emerged in America and Europe to produce welding machines and electrodes as per the requirements.

Alternating current was not invented until 1919 and did not become popular until the 1930s when mass production of electricity began. After this, the electrode with the necessary coating found wide use.

In the 1920s, various types of welding electrodes were developed. During the 1920s, there was considerable debate about the merits of metal-coated and non-metal-coated rods made by extrusion (grinding).

During the 1920s, significant research was carried out into shielding the arc and welding zone by externally applied gases. An atmosphere of oxygen and nitrogen in contact with molten weld metal caused brittle and sometimes porous welds. Engineers used hydrogen as a welding atmosphere.

Hydrogen was replaced by atomic hydrogen in the arc. Atomic hydrogen was formed by exposure to an electrical discharge. This arc produced twice the heat of an oxygen flame.

Atomic hydrogen never became popular, but was used in the 1930s and 1940s for special tool steel applications.

In 1932, for the first time in the world, underwater welding was carried out in the Soviet Union.

Engineers H. M. Hobart and P. C. Devers carried out similar work, but used an atmosphere of argon and helium gases. In its patents filed in 1926, gas arc welding was the harbinger of a new process.

In 1953, Professor Lyubavsky and assistant Novoshilov announced the use of welding with consumable electrodes in a CO2 gas atmosphere. The CO2 process immediately gained popularity due to the fact that it used already developed inert gas equipment. This variation soon became the most popular arc welding technology.

Another option is to use an inert gas with a small amount of oxygen, which provides a stable arc.

How does today's conventional household welding work?

Briefly, how today's ordinary household welding works: electricity is supplied to the electrode and the welded product to create and maintain an arc from a special device.

Under the influence of the arc temperature, the edge of the metal being welded and the metal from the electrode begin to melt.

Due to the fact that all the metals involved are melted, they mix together to form a strong bond, while at the same time the molten slag floats to the surface, which forms a protective film. After the metal hardens, a weld will be formed.

1882 - Benardos created the first welding method using carbon electrodes.

1888 - Slavyanov first used electrodes, the design of which included a metal rod under a layer of flux. In the presence of a state commission, he managed to weld the crankshaft of a steam engine.

1939 - Paton figured out how to automate submerged arc welding, welding fluxes, tank turrets, and the first bridge made of welded elements.

Today's development of science and technology has made it possible to use fundamentally new ways and methods of joining metals.

Source: https://v-nayke.ru/?p=1698

History of welding development. The role of welding in the modern world | mk-soyuz.rf

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, tee, 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, reduces the risk of poor-quality seams,
• 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 metal savings,
• wear-resistant equipment has a large margin of safety, it 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://xn----ntbhhmr6g.xn--p1ai/metallyi/kto-izobrel-svarku

History of welding development. Scientists and their discoveries in the field of welding

articles

• Welding background
• Fundamental discoveries
• Modernity
  • Electric arc welding.
  • Electroslag welding.
  • Contact and press welding.
  • Gas welding and cutting.
  • Beam types of welding.
• Prospects for the development of the welding process

Previous welding history

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: http://home.nov.ru/istoriya-razvitiya-svarki-uchenye-i-ix-otkrytiya-v-oblasti-svarki/

Electric arc welding

Electric arc welding with coated electrode

Electric welding is one of the welding methods that uses an electric arc to heat and melt metal.

The temperature of the electric arc (up to 7000 °C) exceeds the melting point of all existing metals.

History of electric welding[ | ]

1802 - V.V. Petrov discovered the phenomenon of a voltaic electric arc and pointed out that the appearing “white light or flame, from which these coals ignite faster or more slowly, and from which the dark peace can be quite clearly illuminated.”

1803 - V.V. Petrov published the book “News about galvanic-voltage experiments,” where he described methods for making a voltaic column, the phenomenon of an electric arc and the possibility of its use for electric lighting, electric welding and electric soldering of metals.

1882 - N. N. Benardos invented electric welding using carbon electrodes, which he patented in Germany, France, Russia, Italy, England, the USA and other countries, calling his method “electrohephaestus”.

1888 - N. G. Slavyanov was the first in the world to put into practice arc welding with a metal (consumable) electrode under a layer of flux. In the presence of a state commission, he welded the crankshaft of a steam engine.

1893 - At the World Exhibition in Chicago, N. G. Slavyanov received a gold medal for the method of electric welding under a layer of crushed glass.

1905 - V.F. Mitkevich was the first in the world to propose the use of a three-phase arc for welding metals.

1932 - K.K. Khrenov implemented it for the first time in the world in the Soviet Union [2].

1939 - E. O. Paton developed the technology of automatic submerged arc welding, welding fluxes and heads for automatic welding, electric welded tank turrets, and an electric welded bridge.

Process description[ | ]

Electricity is supplied to the electrode and the welded product to form and maintain an electric arc from a welding transformer (or welding unit, welding converter, welding inverter). When the welding electrode and the workpiece come into contact, welding current flows.

Under the influence of the heat of the electric arc (up to 7000°C), the edges of the parts being welded and the electrode metal are melted, forming a weld pool, which remains in a molten state for some time. In the weld pool, the electrode metal is mixed with the molten metal of the product (base metal), and the molten slag floats to the surface, forming a protective film. When the metal hardens, a welded joint is formed.

The energy required to form and maintain an electric arc is obtained from special DC or AC power sources[3].

Consumable and non-consumable electrodes can be used in the electric welding process. In the first case, the formation of a weld occurs when the electrode itself melts; in the second case, when the filler wire (rods, etc.) melts, which is introduced directly into the weld pool.

To protect the weld metal from oxidation, shielding gases (argon, helium, carbon dioxide and their mixtures) supplied from the welding head during the electric welding process are used.

To increase the stability of the electric arc, easily ionized elements (potassium, sodium, calcium) can be introduced into the electrodes [4]..

There are alternating current electric welding and direct current electric welding. When welding with direct current, the weld is obtained with less metal spatter, since there is no zero crossing and no change in current polarity.

DC electric welding machines use rectifiers.

It is possible to control the position of the welding arc when welding with direct current. The arc is a conductor of current and, like an ordinary conductor, is deflected in a magnetic field in accordance with Ampere's law.

Classification[ | ]

Arc welding is classified depending on the degree of mechanization of the process, the type of current and polarity, the type of welding arc, the properties of the welding electrode, the type of protection of the welding zone from atmospheric air, etc.

According to the degree of mechanization, they are distinguished:

• manual arc welding
• mechanized (semi-automatic) arc welding
• automatic arc welding

The assignment of processes to one or another method depends on how the ignition and maintenance of a certain length of the arc, manipulation of the electrode to give the seam the desired shape, movement of the electrode along the line of application of the seam and termination of the welding process are carried out.

In manual arc welding (MMA - Manual Metal Arc), the specified operations necessary to form a seam are performed by a person manually without the use of mechanisms.

With mechanized (semi-automatic) arc welding (MIG/MAG -Metal Inert/Active Gas) with a consumable electrode, the supply of electrode wire into the welding zone is automated, and the remaining operations of the welding process remain manual.

With automatic submerged arc welding, the operations of exciting the arc, maintaining a certain length of the arc, and moving the arc along the seam line are mechanized.

Automatic consumable electrode welding is carried out using welding wire with a diameter of 1-6 mm; in this case, the welding mode (current, voltage, arc speed, etc.)

) is more stable, which ensures uniform quality of the seam along its length; at the same time, greater precision is required in the preparation and assembly of parts for welding.

According to the type of current, they are distinguished:

• electric arc powered by direct current of straight polarity (minus on the electrode);
• electric arc fed by direct current of reverse polarity (plus on the electrode);
• electric arc powered by alternating current.

According to the type of arc they distinguish:

• direct action arc (dependent arc);
• arc of indirect action (independent arc).

In the first case, the arc burns between the electrode and the base metal, which is also part of the welding circuit, and the heat generated in the arc column and at the electrodes is used for welding; in the second, the arc burns between two electrodes.

According to the properties of the welding electrode, they are distinguished:

• consumable electrode welding methods;
• methods of welding with non-consumable electrodes (carbon, graphite and tungsten).

Consumable electrode welding is the most common welding method; in this case, the arc burns between the base metal and the metal rod fed into the welding zone as it melts. This type of welding can be performed with one or more electrodes.

If two electrodes are connected to one pole of the arc power source, then this method is called two-electrode welding, and if more - multi-electrode beam welding. If each of the electrodes receives independent power, the welding is called double-arc (multi-arc) welding.

In fusion arc welding, the arc efficiency reaches 0.7-0.9.

According to the conditions for monitoring the arc combustion process, are distinguished:

• open;
• closed;
• half-open arc.

When the arc is open, visual observation of the arc burning process is carried out through special protective glasses - light filters. An open arc is used in many welding methods: manual welding with metal and carbon electrodes and welding in shielding gases.

The closed arc is located entirely in the molten flux - slag, base metal and granular flux, and is invisible. A half-open arc is characterized by the fact that one part of it is in the base metal and molten flux, and the other is above it. The process is observed through light filters.

Used for automatic flux welding of aluminum.

Based on the type of protection of the welding zone from ambient air, there are:

• arc welding without protection (bare electrode, electrode with a stabilizing coating);
• arc welding with slag protection (thickly coated electrodes, submerged arc);
• arc welding with slag-gas protection (thickly coated electrodes);
• arc welding with gas protection (in a protective gas environment) (MIG-MAG);
• arc welding with combined protection (gas environment and coating or flux).

Stabilizing coatings are materials containing elements that easily ionize the welding arc. They are applied in a thin layer to electrode rods (thin-coated electrodes) intended for manual arc welding.

Protective coatings are a mechanical mixture of various materials designed to protect the molten metal from exposure to air, stabilize the arc, alloy and refine the weld metal.

The most widely used are medium- and thick-coated welding electrodes intended for manual arc welding and surfacing, manufactured in special workshops or factories.

Recently, plasma welding has become widespread, where an arc between inert non-consumable electrodes is used to heat an intermediate carrier, for example, water steam, at high temperatures. Welding with atomic hydrogen is also known, produced in an arc between and releasing heat when recombining into molecules on the parts being welded.

Notes[ | ]

1. Chekanov A. A. Nikolai Nikolaevich Benardos. - M.: Nauka, 1983.
2. “Handbook for a young electric welder on manual welding”, G. G. Chernyshov, V. B. Mordynsky, Moscow, “Machine Building”, 1987; page 66
3. “Welding: Welding and cutting of metals: a textbook for beginners. prof. education/G. G. Chernyshov. - M.: Publishing Center "Academy", 2008 - p. 496
4. Documentary film "Arc Welding"

Literature[ | ]

Nikolaev G. A. Welding in mechanical engineering: A reference book in 4 volumes - M.: Mechanical Engineering, 1978 (1-4 volumes).

Links[ | ]

Source: https://encyclopaedia.bid/%D0%B2%D0%B8%D0%BA%D0%B8%D0%BF%D0%B5%D0%B4%D0%B8%D1%8F/%D0% A1%D0%B2%D0%B0%D1%80%D0%BE%D1%87%D0%BD%D1%8B%D0%B9_%D0%B0%D0%BF%D0%BF%D0%B0% D1%80%D0%B0%D1%82

History of development, types and scope of application of welding equipment

Welding of refractory materials is one of the foundations of the development of human civilization. With its emergence and use in construction, it became possible to erect high-rise buildings, build bridges over rivers, and conduct utility lines. Technologies for combining metals have even penetrated into the field of human health – medicine. We will introduce you to the history of welding, types of equipment and its scope of application.

The history of welding methods

Welding joints began to be used in ancient times by fusing gold items that were found in the Egyptian pyramids using tin soldering. In Pompeii, during excavations, lead water pipes with a soldered seam (transverse) were discovered.

We also know that ancient craftsmen, during forging, connected parts of the product by heating the metal to a plastic state. This is how blades and swords appeared, consisting of several strips of metal. In the Middle Ages, large artillery cannons were made in a similar way, reinforcing a forged pipe with outer rings that were connected to it using forge welding. Ancient buildings built during the Renaissance contain steel connections to support load-bearing structures.

The progress of the 19th and 20th centuries gave a new impetus to the use of welding technologies. The study of direct current contributed to the emergence of new approaches, one of which was electric welding. The first to use such a method was Petrov, a professor at the St. Petersburg Medical and Surgical Academy, who discovered the arc discharge in 1802.

And he later used the electric arc method to melt metals. At first, non-consumable carbon electrodes were used in such welding, and then, in 1988, metal electrodes were used for the first time. Unfortunately, the arc temperature was uneven, so the seam itself was uneven and porous.

Only with the use of fluxes has the welding process become more stable and of higher quality.

The twentieth century was marked by the emergence of many devices that improved and simplified the work process. Welding machines were one of these units. Although the technological level of the devices differs from the earliest ones, the operating principle remains the same.

The first welding machine with an oxy-acetylene welding torch was designed in 1903, and in 1906 acetylene generators for industry appeared. In 1940, the first use of a tungsten electrode using helium was made, and since 1946, a safer and cleaner gas, argon, began to be used.

Since the early 60s of the 20th century, several new welding technologies have appeared: using multiple electrodes, using a powder electrode, gas laser cutting.

Types of equipment

The welding arc occurs under the influence of power sources that allow maintaining a stable discharge. For constant and uniform operation, special equipment was created, which has different purposes, sizes and applications. This includes:

• Electrodes and wire are the type of devices without which welding is basically impossible. They may differ in polarity, type of current used (direct or alternating), coating and material of manufacture.
• Semi-automatic machines for welding in an inert/active gas environment. Complex and expensive devices, but with good performance; convenient to use. They can work with iron, steel, aluminum. Welding is carried out with wire made of various metals with a thickness of 0.6 - 1.2 mm in a protective gas environment. A multi-stage current regulator allows you to make the process smoother. Sometimes the wire speed changes. These two parameters determine the operating mode.
• Devices with an alternating current transformer or transformers are used for welding with a consumable metal electrode with a coating. They are distinguished by their simplicity of design, reliability, low cost and are the most common. They work using consumable electrodes with a rutile or basic (calcium fluoride) coating, designed to protect the weld pool or impart various physicochemical properties to the finished joint, for example, alloy it. The welding method for such a device is butt and overlap.
• Devices with a DC transformer or rectifiers for working with consumable electrodes. The design of the device includes a diode or thyristor rectifier, which makes the alternating current unidirectional, while losing some of its power. The unit is more complex, heavier and more expensive. But, nevertheless, working on it is more comfortable, since the arc is more stable. Can weld ferrous metals, stainless steel, non-ferrous metals using appropriate electrodes.
• Inverters, also called pulse inverters. One of the most modern and advanced welding machines. They have various modifications, are famous for their low weight and improved quality of work due to the installed supply voltage stabilization circuits. The inverter is a direct current device and has a voltage rectification transformer at the input and output. The cost of such a device is quite high, but its advantages prevail, and it enjoys well-deserved success.
• TIG machines with argon-arc welding, allowing for high-quality fusion. This is necessary to connect particularly critical areas. When working, graphite and tungsten non-consumable electrodes are used.
• Spot welders or spotters for the local connection of two workpieces or parts.
• Plasma cutting is used in the process of cutting metal. The principle is to cut the product with a plasma jet followed by evaporation (washing out) by an ionized stream of material particles.

Scope of application

Welding equipment is as in demand today as it was at the beginning of its use. These devices have different areas of application, and now we will look at for which areas it is logical to choose a specific welding unit or connection method.

Transformers are the oldest technology, rather bulky and heavy devices that require a large amount of electricity to operate. In addition, they are sensitive to voltage fluctuations.

Therefore, their use is possible in cases of connecting rough seams of the most popular grades of steel and certain types of cast iron. Although, experienced welders can make excellent seams even with such equipment.

It all depends on the skill of the master, so transformers are quite common in industry.

Rectifiers that operate with alternating current can weld not only ferrous metals, but also any non-ferrous metals - aluminum, copper, titanium, nickel, and alloys of these metals. Therefore, the scope of application of such devices is very wide - from industry to domestic needs.

Semi-automatic devices are designed to operate in a gas environment. The electrode wire is fed automatically, which is why the devices got their name. This device makes it possible to obtain a seam of the required thickness and quality. Semi-automatic machines work with metals and alloys with any sheet sizes. The only drawback is the splashing of hot material and the creation of burns.

Inverters . Their device facilitates precise adjustment of the process and, as a result, obtaining high-quality seams. Even thin-walled metal can be welded with an inverter machine.

TIG machines , although they have low productivity, are popular due to the excellent quality of the seam with low metal loss during operation. They can connect all types of metals and their alloys.

Spot welding is widely used in the automotive industry, large service stations, and car repair shops. The work of a spotter allows you to connect small parts or body parts, so such devices are in deserved demand. By adding special welding pliers to the device, you will successfully use the spot welding method.

Plasma cutting machines can be bulky, large or small household devices. They are used both in industry for cutting metal on a large scale and for domestic purposes.

Despite the large amount of equipment for welding metals, the most popular are small devices for working with a conventional electrode. Simplicity of design and ease of operation allows the use of such units by any person who has little knowledge of welding structures and servicing such equipment.

Source: http://oborudovo.ru/art/svarka_istoria/

What types of welding are there (description and advantages)

So, inverter welding - what is it? Essentially, inverter welding is a process that uses a circuit, system, or device whose job is to create an alternating voltage using a direct current source.

Inverter welding

The general circuit of such a welding machine includes a mains filter, mains rectifier, frequency converter, high-frequency transformer, power rectifier and control system.

Naturally, in order to weld metal structures, it is not enough just a welding machine; you will also need to use various accessories - a mask, holders and, of course, electrodes. Welding without electrodes is simply impossible. In the process of inverter welding, three types of electrodes are used - carbon, alloyed and high-alloyed.

The main advantages of welding work using an inverter machine are as follows:

• ignition is easy and quick, the arc burns steadily and has good elasticity;
• high quality weld;
• low energy costs during operation;
• fairly good efficiency;
• supply voltage fluctuations do not affect the quality parameters of welding joints;
• These devices are lightweight and mobile.

Naturally, like any process, inverter welding also has its disadvantages: inverter-type welding machines, like any complex electronic devices, are highly susceptible to the influence of water, dust and frost. For this reason, devices of this type must be stored in a room that provides the required parameters of dryness and warmth.

Another important point is the care of the welding machine; periodically it will be necessary to open the housing and blow through the components of the device with compressed air.

Argon welding

Argon welding is one of the types of welding work that allows welding complex and refractory metals. Using this welding method, aluminum and other metals that undergo an oxidation process when exposed to air are often welded.

Argon welding is most often used in industries such as the automotive industry, during the repair of various vehicle components made of aluminum. In addition, argon welding is used in the metallurgical industry, for example, to carry out hot processing of titanium, tantalum, niobium, beryllium, zirconium, hafnium, tungsten, uranium, thorium and to process alkali metals.

The use of argon as a gas is a fairly common practice; for example, light bulbs also contain it.

Argon welding is a rather complex process that requires high qualifications and modern equipment. However, the result of this process is at the same level - the seams are smooth, sometimes almost invisible, and at the same time very durable.

Argon-arc welding is carried out using tungsten electrodes and a ceramic nozzle. It is through this nozzle that argon is supplied to the welding site, which prevents the metal from coming into contact with the atmosphere. This, in turn, prevents oxidation of the metal and ensures a strong weld.

Argon welding can be divided into two types: manual welding and automatic

So what is good about argon arc cutting and welding of metal structures? To begin with, it is worth noting that due to the fact that this process uses modern equipment, the operating time is significantly reduced. In addition to this, the argon jet during welding work, in addition to protecting the metal from the influence of air, also blows away everything unnecessary and unnecessary.

Lastly, but most importantly, this type of welding work is very economical. This is due to the fact that with the help of argon, the electric arc is compressed and concentrated in a narrow area. For this reason, with relatively low energy costs, it is possible to reach a temperature of the cutting zone of the order of 40006000°C.

Argon arc welding

If you need to weld a steel structure, then, without thinking twice, you will pick up a welding machine and easily cope with this task. But what to do if welding work needs to be done, for example, for an aluminum structure? This is where argon arc welding can help you.

Argon arc welding is welding using an electric arc in an inert argon environment. Consumable or non-consumable electrodes can be used for this welding. A tungsten electrode is most often used as a non-consumable electrode.

The arc burns from the workpiece being welded to a non-consumable electrode (as already mentioned, most likely tungsten). The electrode is fastened to the burner, through the nozzle of which protective gas is supplied. The filler material is supplied to the arc zone from outside and is not included in the electrical circuit.

Argon welding can be performed in manual mode, when the welder controls the torch and filler rod, and in automatic mode, when the movement of the torch and filler wire is carried out without the help of a worker.

When welding with a non-consumable electrode, unlike welding with a consumable electrode, during ignition of the arc the electrode does not touch the product for such reasons. To begin with, argon has a high ionization potential, for this reason ionization of the arc gap using a spark from the electrode to the product is a rather difficult task.

In the case of argon welding using a consumable electrode, after the wire touches the part, the arc zone is saturated with metal vapors, which have an ionization potential almost three times lower than that of argon, as a result of which the arc is ignited.

In addition, if the part touches the tungsten electrode, things such as contamination and intense melting will occur. For this reason, during argon welding using a non-consumable electrode, a device called an “oscillator” is connected in parallel to the power supply network to ignite the arc.

Using an oscillator, to ignite the arc, high-frequency high-voltage pulses are supplied to the electrode, ionizing the arc space and ensuring ignition of the arc when the welding current is turned on. If argon welding is performed with alternating current, when the arc is ignited, the oscillator begins to work as a stabilizer, supplying pulses to the arc when the polarity changes.

This is necessary to prevent deionization of the arc space and ensure stable arc combustion.

During DC welding, the anode and cathode produce different heat. When currents are less than 300 A, the anode generates more heat than the cathode, 70 to 30 percentage, for this reason straight polarity is usually used to ensure maximum penetration of the part and minimal heating of the electrode.

When welding all steels, titanium and other materials except aluminum, straight polarity is used. When welding aluminum, alternating current is used to improve the destruction of the oxide film.

Argon is sometimes mixed with 3–5% oxygen to reduce porosity. This causes more active protection of the metal. Argon in its pure form protects the metal from phenomena such as moisture or other inclusions that enter the welding zone. And with the help of oxygen, harmful impurities are burned out, or released outside. And this helps fight porosity.

Semi-automatic welding machine without gas

If you decide to buy a semi-automatic welding machine without gas, then most likely you are already faced with a huge variety of different options on the market. Let's try to figure out what this device should look like in general.

The welding machine must be inexpensive and powerful. It is best for it to work semi-automatically, from direct current using a melting wire. It is desirable that in the machine, in addition to the mode of operation without gas on flux-cored wire, there is also the possibility of operating on gas (carbon dioxide and argon).

An important factor is the choice of the manufacturer. The manufacturer of the device you choose should be among the leaders in such areas as industrial and household production of equipment for welding work. This company must be officially represented on the market of your country, and have all quality and safety certificates, as well as have service centers.

The wire feed should be adjusted smoothly. It should be possible to implement stepwise power adjustment of welding currents from 50 to 140 A. Even a 5-kilogram spool of wire should be placed in the machine. The device must be equipped with thermal protection and forced air cooling. The machine must be able to operate with power from weak networks.

The winding in the device transformer must be made of copper. The device must be multifunctional; in addition to being used at home, the device must also cope with industrial needs (for example, a repair shop and service station). It would be good if the device is equipped with wheels for ease of transportation.

Well, lastly, and most importantly, when choosing a semi-automatic welding machine without gas, go to the Internet and carefully study the reviews of this device from people who have used it and who have something to compare with.

Source: http://postroyka-dom.com/kakie-vidy-svarki-byvayut-opisanie-i-preimushhestva/