How to cook with a gas burner. How to use gas welding correctly. Materials for gas welding

This method of joining metal parts, like gas welding, is more than a hundred years old. During this time, this technology has continued to be successfully improved, although other welding methods using an electric arc are developing more actively and are replacing welding using a gas torch.

Pros and cons of gas welding

A metal joining method such as gas welding involves melting the materials to be joined, resulting in a homogeneous structure. Gas combustion, due to which the heating and melting of the metal is carried out, is ensured by introducing pure oxygen into the gas mixture. This method of joining metals has a number of advantages.

This welding method does not require the use of complex equipment (welding inverter or semi-automatic machine).
All consumables for such welding are easy to purchase.
Gas welding (respectively, and gas welding of pipes) can be performed even without a powerful source of energy and sometimes without special protective equipment.
The process of such welding lends itself well to regulation: you can set the required power of the burner flame, control the degree of metal heating.

This method also has disadvantages.

Metal heats up very slowly, as opposed to using an electric arc.
The heat zone that is formed by a gas burner is very wide.
It is very difficult to concentrate the heat generated by a gas burner, it is more dissipated in comparison with the electric arc method.
Gas welding can be attributed to a rather expensive method of joining metals when compared with. The cost of oxygen and acetylene consumed significantly exceeds the cost of electricity consumed for welding similar parts.
When welding thick metal parts, the speed of the joint is significantly reduced. This is due to the fact that the concentration of heat when using a gas burner is very low.
Gas welding is difficult to automate. It is possible to mechanize only the process of gas welding of thin-walled pipes or tanks, which is performed using a multi-flame torch.

Materials for gas welding

Gas welding technology involves the use of various types of gases, the choice of which depends on a number of factors.

One of the gases used for welding is oxygen. This gas is characterized by the absence of color and odor, it acts as a catalyst, activating the processes of melting of the material to be joined or cut.

In order to store and transport oxygen, special cylinders are used, in which it is contained under constant pressure. Oxygen can ignite on contact with technical oil, so the very possibility of such contact should be excluded. Oxygen cylinders must be stored in rooms protected from heat and sunlight.

Welding oxygen is obtained by separating it from ordinary air, for which special devices are used. Depending on the degree of its purity, oxygen is of three types: the highest (99.5%), first (99.2%) and second (98.5%) grade.

For various manipulations with metals (welding and cutting), the colorless gas acetylene C2H2 is also used. Under certain conditions (pressure exceeding 1.5 kg / cm2 and temperatures above 400 degrees), this gas can explode spontaneously. Acetylene is obtained by the interaction of calcium carbide and water.

The advantage of using acetylene when welding metals is that its combustion temperature allows this process to be carried out without problems. Meanwhile, the use of cheaper gases (hydrogen, methane, propane, kerosene vapors) does not make it possible to obtain such a high combustion temperature.

Wire and flux for welding

To carry out welding of metals, in addition to gas, are also needed. It is due to these materials that the weld is created, all of its characteristics are formed. The wire used for welding must be clean, free from signs of corrosion and paint on its surface. In some cases, a strip of the same metal that is being welded can be used as such a wire. In order to protect the weld pool from external factors, it is necessary to use a special flux. Boric acid and borax are often used as such a flux, which are applied directly to the surface of the metal to be welded or to the wire used for welding. Gas can be performed without flux, and when connecting parts made of aluminum, copper, magnesium and their alloys, such protection is necessary.

Gas welding equipment

Gas welding technology involves the use of certain equipment.

Water seal

A water seal is necessary to ensure the protection of all elements of the equipment (acetylene generator, pipes) against back draft of fire from the burner. Such a seal, in which the water must be at a certain level, is placed between the gas burner and the acetylene generator.

Cylinder containing gas

Such cylinders are painted with different paints, depending on which gas is planned to be stored in them. Meanwhile, the upper part of the can is not painted in order to exclude contact of the gas with paint components. It should also be borne in mind that copper valves must not be installed on cylinders in which acetylene is stored, as this can lead to a gas explosion.

Reducer

It is used to reduce the pressure of the gas leaving the cylinder. Reducers can be direct or reverse acting, and for liquefied gas, models with ribbing are used, which exclude its freezing at the exit.

Special hoses

Gas welding cannot be carried out without the use of special hoses, through which both gas and flammable liquids can be supplied. Such hoses are divided into three categories, marked with 1) a red stripe (operate at pressures up to 6 atmospheres), 2) a yellow stripe (for the supply of flammable liquids), 3) a blue stripe (operate at pressures up to 20 atm).

Burner

Mixing of gases and their combustion is ensured through the use of a burner, which can be injector or non-injector type. Burners are also classified according to their power, which characterizes the amount of gas passed per unit of time. So, there are burners of large, medium, small and micro-low power.

Special table

Gas welding is carried out at a specially equipped place called a post. In fact, such a place is a table, which can be with a swivel or fixed table top. This table, equipped with exhaust ventilation and everything necessary for storing auxiliary tools, greatly facilitates the work of the welder.

Features of performing gas welding

The flame parameters are adjusted using a reducer, which allows you to change the composition of the gas mixture. With the help of a reducer, three main types of flame can be obtained: reducing (used for welding almost all metals), oxidizing and with an increased amount of combustible gas. When welding metals in a molten pool, two processes occur simultaneously - oxidation and reduction. At the same time, when welding aluminum and magnesium, oxidation processes are more active.

The welding seam itself and the area adjacent to it are characterized by different parameters. So, the section of metal adjacent to the seam is characterized by the minimum strength, it is he who is most prone to destruction. The metal adjacent to this zone has a structure with large grains.

To improve the quality of the seam and the area that adjoins it, additional heating or the so-called thermal forging of the metal is performed.

Welding technologies for various metals have their own nuances.

Gas is performed using any gas. As a filler material for welding such steels, a wire made of steel containing a small amount of carbon is used.
Welding methods are selected depending on their composition. So, heat-resistant stainless steels are cooked using wire containing chromium and nickel, and some grades require the use of filler material additionally containing molybdenum.
Cast iron is cooked with a carburizing flame, which prevents the pyrolysis of silicon and the formation of grains of brittle white cast iron.
For copper welding, a higher power flame must be used. In addition, due to the increased fluidity of copper, parts from it are welded with a minimum gap. Copper wire is used as a filler material, as well as a flux, which promotes deoxidation of the weld metal.
When

How to cook with gas welding

Nowadays, gas welding is widely used for repair work in the field of shipbuilding, automotive, construction. In the process of gas flame welding in an open torch, the base and filler material melts. During gas welding, the metal is gradually heated. Due to this, it has found wide application in welding non-ferrous metals, cast iron and steel.

The flame in the burner is supported by the supply of combustible gases in the cylinder: propane, diacin, hydrogen, methane, acetylene, oxygen and others. When carrying out gas welding, safety precautions must be followed very carefully. Within a radius of a meter, there should be no flammable objects near you. It will not be superfluous to stock up on a container of water.

Gas welding is preferred because of its simplicity and mobility.

The gas welding process is simple, so you can easily master the technique of heating and welding. The main thing for the welder is to master the work with the torch and rod. This will ensure high-quality performance of gas welding works.

Those who are conducting gas welding for the first time, as a rule, have many questions related to the technique, methodology and the process of gas welding itself. The novice welder tries to choose the most optimal technique for himself, depending on the type of materials used in the welding process.
To skillfully approach the welding process, you can use the tips that will certainly help you.

Instructions for working with gas welding

First you need to choose the equipment. Do not forget that during the welding process you will have to work with a gas cylinder. Therefore, it is necessary to become well acquainted with the safety rules.

Depending on the type of surface to be welded, a specific welding technique is selected.

Acetylene is the main component in the gas welding process. Dissolved (in a cylinder) or gaseous acetylene is used for welding. Acetylene cylinders are used for gas welding of any complexity, both at the household level and in high-tech welding. Acetylene is one of the highest quality flame sources. This is due to the fact that there is no need to use any oxidizing agent.

First, it is necessary to prepare a gas cylinder, with the help of which oxygen-acetylene gas welding will be carried out, given the hard-to-reach places.
You will also need a torch with four tips. To practice welding skills, use the smallest tip size first. Try to maintain pressure in all hoses of the device. The pressure for oxygen and for acetylene must be different. It is necessary to ensure that the pressure indicators remain at the level: for oxygen not more than 0.3 MPa, for acetylene - not less than 1 kPa.

In the process of gas welding, you can use an oxygen hose, which belongs to the III class. It will supply oxygen to the gas cylinder at the optimum pressure, as provided by the gas welding technique for small joints.

In order for the seam when welding surfaces to be of high quality and beautiful, use G3. Its application requires skill and more stringent safety requirements. In any case, you should be wearing a protective uniform - these are compacted pants and a jacket. The head must be protected by a cap. The face must be completely covered using a special mask.

You can fully master the art of gas welding only after studying and completing special courses. This will help you select the right gas welding torch. When performing gas welding, it is necessary to correctly position the device relative to the surfaces to be welded, while observing the optimal angle. This is necessary to form a beautiful and even seam. At the end of gas welding, to give the product an aesthetic appearance, you need to carefully clean the scale.

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Gas welding is relatively simple, does not require complex, expensive equipment and a source of electricity.

The disadvantage of gas welding is the slower, compared to the arc, heating rate of the metal and a large zone of thermal effect on the metal. With gas welding, the concentration of heat is less, and the warpage of the parts to be welded is greater.

Due to the relatively slow heating of the metal by the flame and the low concentration of heat, the productivity of gas welding decreases with an increase in the thickness of the metal being welded. For example, with a steel thickness of 1 mm, the gas welding speed is about 10 m / h, with a thickness of 10 mm - only 2 m / h. Therefore, gas welding of steel with a thickness of more than 6 mm is less productive than arc welding.

The cost of acetylene and oxygen is higher than the cost of electricity, so gas welding is more expensive than electric welding. The disadvantages of gas welding also include explosion and fire hazard in case of violation of the rules for handling calcium carbide, flammable gases and liquids, oxygen, cylinders with compressed gases and acetylene generators. Gas welding is used in the following work: manufacture and repair of steel products 1-3 mm thick; welding of vessels and tanks of small capacity, welding of cracks, welding of patches, etc.; repair of cast iron, bronze, silumin; welding of joints of pipes of small and medium diameters; manufacturing of products from aluminum and its alloys, copper, brass and lead; manufacturing of structural units from thin-walled pipes; surfacing of brass on steel and cast iron parts; joining ductile and ductile iron using filler rods made of brass and bronze, low-temperature welding of cast iron.

Almost all metals used in technology can be joined by gas welding. Cast iron, copper, brass, lead are easier to gas welding than arc welding.

GAS WELDING TECHNIQUE

Gas welding can be used for bottom, horizontal, vertical and overhead seams. Ceiling seams are most difficult to make, as the welder must support and distribute liquid metal along the seam using the pressure of the flame gases. Most often, butt joints are performed with gas welding, less often fillet and end joints. It is not recommended to perform overlapping and T-joints with gas welding, since they require intensive heating of the metal and are accompanied by increased warpage of the product.

Flanged joints of thin metal are welded without filler wire. Intermittent and continuous seams are used, as well as single-layer and multi-layer seams. Before welding, the edges are thoroughly cleaned of traces of oil, paint, rust, scale, moisture and other contaminants.

Table 10 shows the preparation of edges for gas welding of carbon steels with butt welds.

BURNER MOVEMENT WHEN WELDING

The flame of the burner is directed to the metal being welded so that the edges of the metal are in the reduction zone, at a distance of 2–6 mm from the end of the core. Do not touch the molten metal with the end of the core, as this will cause carburization of the bath metal. The end of the filler wire should also be in the reduction zone or immersed in a molten metal bath. In the place where the end of the flame core is directed, the liquid metal is slightly blown to the sides by gas pressure, forming a depression in the weld pool.

The heating rate of the metal in gas welding can be adjusted by changing the angle of inclination of the nozzle to the metal surface. The larger this angle, the more heat is transferred from the flame to the metal and the faster it will heat up. When welding thick or heat-conductive metal (for example, red copper), the angle of inclination of the nozzle a is taken more than when welding thin or with low thermal conductivity. In fig. 86, a shows the angles of inclination of the nozzle recommended for left-hand (see § 4 of this chapter) welding of steel of various thicknesses.

In fig. 86, b shows how to move the mouthpiece along the seam. The main thing is to move the mouthpiece along the seam. Transverse and circular movements are auxiliary and serve to regulate the rate of heating and melting of the edges, and also contribute to the formation of the desired shape of the weld.

Method 4 (see Fig. 86, b) is used when welding thin metal, methods 2 and 3 - when welding metal of medium thickness. During welding, one should strive to ensure that the metal of the bath is always protected from the ambient air by gases of the reducing flame zone. Therefore, method 1, in which the flame is periodically diverted to the side, is not recommended, since it may oxidize the metal with atmospheric oxygen.

BASIC METHODS OF GAS WELDING

Left welding (Fig. 87, a). This method is the most common. It is used for welding thin and low-melting metals. The torch is moved from right to left, and the filler wire is led in front of the flame, which is directed to the unwelded section of the seam. In fig. 87, and below is a diagram of the movement of the nozzle and wire with the left-hand welding method. Flame power in left-hand welding is taken from 100 to 130 dm 3 of acetylene per hour per 1 mm of metal (steel) thickness.

Right hand welding (Fig. 87, b). The burner is led from left to right, the filler wire is moved after the burner. The flame is directed to the end of the wire and the welded section of the seam. Transverse vibrational movements are not performed as often as in left-hand welding. Slight lateral vibrations are made with the mouthpiece; when welding metal with a thickness of less than 8 mm, the mouthpiece is moved along the axis of the seam without transverse movements. The end of the wire is kept immersed in the weld pool and the liquid metal is mixed with it, which facilitates the removal of oxides and slags. The heat of the flame is less dissipated and used better than left-hand welding. Therefore, in right-hand welding, the seam opening angle is made not 90 °, but 60-70 °, which reduces the amount of deposited metal, wire consumption and warpage of the product from shrinkage of the seam metal.

It is advisable to use right-hand welding to join metal with a thickness of more than 3 mm, as well as a metal of high thermal conductivity with groove edges, such as red copper. Weld quality in right-hand welding is better than in left-hand one, because the molten metal is better protected by the flame, which simultaneously anneals the weld metal and slows down its cooling. Due to the better use of heat, right-hand welding of thick metal is more economical and more productive than left-hand welding - the speed of right-hand welding is 10–20% higher, and gas saving is 10–15%.

Right-hand welding connects steel up to 6 mm thick without beveling the edges, with full penetration, without back welding on the back side. Flame power for right-hand welding is taken from 120 to 150 dm 3 of acetylene per hour per 1 mm of metal (steel) thickness. The mouthpiece should be inclined to the welded metal at an angle of at least 40 °.

For right-hand welding, it is recommended to use filler wire with a diameter equal to half the thickness of the metal being welded. For left-hand welding, use a wire with a diameter of 1 mm larger than for right-hand welding. Wire with a diameter of more than 6-8 mm is not used for gas welding.

Through bead welding (Fig. 88). The sheets are installed vertically with a gap equal to half the sheet thickness. The flame of the burner melts the edges, forming a round hole, the lower part of which is melted with filler metal to the entire thickness of the metal to be welded. Then the flame is moved higher, melting the upper edge of the hole and applying the next layer of metal to the lower side of the hole, and so on until the entire seam is welded. The seam is obtained in the form of a through bead connecting the sheets to be welded. The weld metal is dense, without pores, shells and slag inclusions.

Tray welding. This method is used to weld butt and fillet joints of metal of small thickness (less than 3 mm) with filler wire. When a bath with a diameter of 4-5 mm is formed on the seam, the welder inserts the end of the wire into it and, having melted a small amount of it, moves the end of the wire into the dark, reducing part of the flame. At the same time, he makes a circular movement with the mouthpiece, moving it to the next section of the seam. The new tray should overlap the previous one by 1/3 of the diameter. To prevent oxidation, the end of the wire should be kept in the reducing flame zone, and the flame core should not be immersed in the bath in order to avoid carburization of the weld metal. Welded in this way (with lightweight seams), thin mild steel and low alloy steel sheets and pipes give excellent quality joints.

Multilayer gas welding. This welding method has a number of advantages over single-layer welding: a smaller metal heating zone is provided; annealing of the underlying layers is achieved during surfacing of subsequent ones; it is possible to forge each layer of the seam before applying the next. All this improves the quality of the weld metal. However, multilayer welding is less productive and requires more gas consumption than single-layer welding, therefore it is used only in the manufacture of critical products. Welding is carried out in short sections. When applying layers, you need to ensure that the joints of the seams in different layers do not coincide. Before applying a new layer, you need to thoroughly clean the surface of the previous one from scale and slag with a wire brush.

Welding with an oxidizing flame. This method is used to weld mild steels. Welding is carried out with an oxidizing flame having the composition

To deoxidize the iron oxides formed in this process in the welding pool, wires of grades Sv-12GS, Sv-08G and Sv-08G2S according to GOST 2246-60 are used, containing increased amounts of manganese and silicon, which are deoxidizers. This method increases productivity by 10-15%.

Welding propane - butane-oxygen flame... Welding is carried out with an increased oxygen content in the mixture

in order to increase the flame temperature and increase the penetration and fluidity of the bath. To deoxidize the weld metal, wires Sv-12GS, Sv-08G, Sv-08G2S, as well as Sv-15GYu wire (0.5-0.8% aluminum and 1-1.4% manganese) are used in accordance with GOST.

Research by A.I. Shashkov, Yu.I. Nekrasov and S.S. Vaksman established the possibility of using in this case the usual low-carbon filler wire Sv-08 with a deoxidizing coating containing 50% ferromanganese and 50% ferrosilicon, diluted in liquid glass. The weight of the coating (excluding the weight of the liquid glass) is 2.8-3.5% by weight of the wire. Coating thickness: 0.4-0.6 mm when using a wire with a diameter of 3 mm and 0.5-0.8 mm with a diameter of 4 mm. Propane consumption 60-80 l / h per 1 mm of steel thickness, w \u003d 3.5, the angle of inclination of the bar to the plane of the metal is 30-45 °, the groove angle is 90 °, the distance from the core to the bar is 1.5-2 mm, to metal 6-8 mm. This method can weld steel up to 12 mm thick. The best results were obtained when welding steel 3-4 mm thick. Wire Sv-08 with the specified coating is a full-fledged substitute for more scarce grades of wire with manganese and silicon for propane-butane welding.

Features of welding various seams. Horizontal seams are welded with the right method (Fig. 89, a). Sometimes welding is done from right to left, holding the end of the wire on top and the mouthpiece on the bottom of the bath. The weld pool is placed at an angle to the weld axis. This facilitates the formation of the seam, and the metal of the bath is kept from draining.

Vertical and inclined seams are welded from bottom to top by the left method (Fig. 89, b). With a metal thickness of more than 5 mm, the seam is welded with a double roller.

When welding ceiling seams (Fig. 89, c), the edges are heated until the beginning of melting (fogging) and at this moment a filler wire is introduced into the bath, the end of which is quickly melted. The metal of the bath is kept from flowing down by the rod and the pressure of the flame gases, which reaches 100-120 gf / cm 2. The bar is held at a slight angle to the metal to be welded. Welding is carried out in the right way. It is recommended to use multi-layer seams welded in several passes.

Welding of metal with a thickness of less than 3 mm with flanged edges without filler metal is carried out by spiral (Fig. 89, d) or zigzag (Fig. 89, e) movements of the mouthpiece.

Administration Overall assessment of the article: Posted: 2011.05.31

Gas welding is the joining of metals by forming weld puddles when the metal surfaces are heated by a high-temperature flame, which is formed during the combustion of a mixture of acetylene and oxygen, in this case oxygen is a catalyst that leads to instantaneous ignition of acetylene and the formation of a welding stream.

In some cases, acetylene can be replaced by propane-butane, methane, gasoline vapors (jewelry industry and welding of precious metals), hydrogen obtained during the electrolysis of distilled water.

Combustible gas, together with oxygen, is fed into the welding device and removed through a calibrated nozzle, after which ignition occurs, the flow is adjusted using valves.

In this case, the flame consists of three components:

nucleus;
recovery;
torch.

The highest temperature is in the core of the flame, but the welding is done partly between the recovery and the core.

In addition, the effect of an open high-temperature flame on the welded surfaces protects the weld pool from interaction with air.

Due to its high ability to cut metals, this type of welding is also used for shaped and high-precision cutting of metal sheets, the manufacture of parts and products.

Among the many technologies for metal processing, laser cutting stands out for its economy and efficiency. Read about laser cutting metal

Direct welding with an acetylene torch means heating the welded edges, melting them and joining them;
Surfacing, spraying.

This type of use of gas welding involves the use of a filler rod made of soft metal, which additionally saturates the weld pool at the fused edges.

The qualitative difference between the two methods lies in the consumption of the gas mixture, time and functionality.

In the first case, a higher gas consumption is required, since the melting of two metal edges requires more temperature than heating a filler rod made of low-melting metals.

Cold welding of linoleum is a very effective and technologically advanced way of bonding linoleum coatings together. More details

Welding with additives is much stronger and more aesthetically pleasing and takes less time for the same reason as lower gas consumption.

The field of application of this type of welding is extensive: welding of thin-walled pipes of technological pipelines, welding of technological products and machine spare parts, surfacing of a bar on spare parts and cast iron parts, heating of forged fragments and forging.

Welding consists of the following elements: a propane cylinder (or any other combustible gas close to inert flow properties), an oxygen cylinder, which is a catalyst for ignition, and a gas cutting, which consists of a bronze tube, two propane control valves and oxygen, at the end of the tube there is a calibrated nozzle-nozzle for atomizing gas under pressure.

Ignition is performed with a special silicon piezo lighter.

Pros:

the most important positive criterion is autonomy and no need for an AC or DC source. This fact makes the use of this type of welding extremely effective in closed objects, construction sites, remote sites, where there is no constant and uninterrupted power source;
adjusting the distance of the welder from the surface of the welding metals and adjusting the temperature regimes allows you to avoid burn-throughs, even if thin-sheet metal plates are being welded;
the equipment is lightweight, highly mobile for movement and transportation;
reliability and quality of the work performed is the main positive characteristic of this type of welding.

low productivity, slow high-precision work that requires;
high temperature, which has a large circumferential range;
expendable materials.

Precautions and rules for using a gas burner

Since the gas burner has a high temperature range of the circumferential action, it is necessary to remember the following safety rules:

all work must be done in leggings, which will protect the welder's palms from burns;
it is also undesirable to look at the core of the flame, since the temperature is above 1000 degrees and the light load adversely affects the cornea of \u200b\u200bthe eye.

Be very careful: it is strictly forbidden to take a gas cutting and open the oxygen cylinder with oil hands, since the interaction of industrial oil and oxygen instantly ignites oxygen and an explosion in the confined space of the cylinder.

Gas cutting and autogenous welding has been a benchmark of quality and functionality for a wide range of industrial applications for over 60 years.

Convenience and affordability, combination of price and quality have brought this type of welding on a par with

Independent, without the participation of professionals, but high-quality and fast assembly of metal structures during repair work, soldering seams, as well as cutting various metal products is possible with the help of a good welding machine for the home. Read about welding machines

Gas welding is preferred because of its simplicity and mobility.

Those who are conducting gas welding for the first time, as a rule, have many questions related to the technique, methodology and the process of gas welding itself. The novice welder tries to choose the most optimal technique for himself, depending on the type of materials used in the welding process. To skillfully approach the welding process, you can use the tips that will certainly help you.

Instructions for working with gas welding

Depending on the type of surface to be welded, a specific welding technique is selected.

First, it is necessary to prepare a gas cylinder, with the help of which the acetylene-oxygen gas welding will be carried out, taking into account the hard-to-reach places. You will also need a torch with four tips. To practice welding skills, use the smallest tip size first. Try to maintain pressure in all hoses of the device. The pressure for oxygen and for acetylene must be different. It is necessary to ensure that the pressure indicators remain at the level: for oxygen not more than 0.3 MPa, for acetylene - not less than 1 kPa.

Gas welding, how to cook with gas welding, gas welding for beginners, How to work with gas welding, how to cook with gas welding

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Gas welding - advantages and disadvantages

Welding first appeared in ancient Egypt. People learned to weld iron at the same time as other methods of processing various metals. Of course, the quality of welding of that time is very different from the quality of our days, but nevertheless, there are still many palaces, temples and other structures to keep on the first structures made by welding.

As paradoxical as it may sound, man at the beginning discovered and improved electric welding. Later, namely, in 1903, a gas welding apparatus was invented in France. Oxygen and acetylene were used in the welding machine. The design of the invented gas apparatus, in principle, is still used, but it has been constantly improved. Equipment, oxygen cylinders, gearboxes and other materials were improved and changed. As in electric arc and laser welding, and in gas, there are peculiarities of the technology for making seams. They must always be taken into account when choosing a particular type of work. Things like balancing welding cost minimization and weld quality are very important.

Consider the benefits of gas welding

Gas welding does not require expensive complex equipment or additional energy sources. In this way, you can weld metal even in an open open field or deep forest. In the third decade of the 20th century, all oil pipelines were welded by gas welding. These features allow you to carry out welding work in any premises, buildings and regions.

It is possible to weld metals with a wide variety of melting points by widely varying the power of the gas welding flame. Materials such as brass, lead, and cast iron are best gas welded. By choosing the right filler wire grade and flame power, high quality welds can be obtained. Gas-acetylene welding is trusted by even the most critical areas. The welded surfaces heat up and cool down very slowly. The flame temperature can be easily changed. When the angle of inclination to the welded surface changes, the flame temperature also changes. The quality and strength of the seams is usually higher than when using electric arc welding. Gas welding can be used to cut, temper and weld various metals.

Disadvantages of gas welding

Gas welding has a large heating zone. If thermally unstable elements are located near the welded place, they will be damaged. It is unprofitable to weld metal with a thickness of more than 5 millimeters. The greater the thickness, the more the welding performance decreases. In such cases, it is better to use electric arc welding.

In gas welding, very dangerous substances are used, such as hydrogen, acetylene, which, when combined with oxygen, give an explosive mixture. Gas cylinders should be as far away from organic substances as possible. Otherwise, non-observance of safety precautions will lead to an explosion and fire. Gas welding does not lend itself to mechanization. Cannot alloy directed metal. With gas welding, it is not recommended to weld high carbon metals. The welded surfaces heat up and cool down very slowly.

A feature of the technology is that during gas welding, the surface slowly heats up and cools down. The advantage of slow heating / cooling is that many alloys and metals require gradual heating conditions. Non-ferrous metals are welded very well with gas welding. Also, gas welding has several features. Three kinds of oxygen are used. Generally, the purer the oxygen, the faster the cutting process and the better the edge quality. Gas welding takes place in the construction industry. It will be used in various types of production for a very long time.

Information on our website: painting work tsp technology of finishing work technology cards in construction technology of finishing work technology of installation of metal columns

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Everything You Need to Know About Gas Welding - Welder's Guide

Gas welding is a special type of welding, since its principle of operation is based on the method of metal melting. In order to carry out gas welding, the possibility of using a variety of fuels and gases is allowed. Therefore, welding can be, for example, oxygen-hydrogen, gasoline-oxygen, and so on. Also, there is oxygen-acetylene gas welding, and other types that are used both in bulk and in single applications. The main, significant technological difference between gas welding, from any other type of welding, is a smooth and quieter, slow heating of the metal.

This is the main difference - the use of a gas flame, as a method for welding, and a welding arc. This application has both advantages and disadvantages. Thus, gas welding is used in a number of such cases:

1). For steels 0.2-5 mm thick;

2). For welding non-ferrous metals;

3). For any metals that require smooth heating and slow damping during the welding process;

4). For metals that require preheating (again, for non-ferrous metals, and for cast iron);

five). For brazing processes;

6). For surfacing and surfacing works.

Gas welding has obvious advantages such as comparative simplicity and portability, which allows it to be used in many types of work. Slow heating of the metal using a gas flame, as a rule, reduces the degree of productivity of gas welding, with a thickening of the metal, and it turns out that with a thickness of 8-10 mm, gas welding becomes economically unprofitable, although it is still technically suitable for work with metals, 30-40 mm thick. Also, the fact that the gas flame heats up for a long time, the welding section becomes the reason that the near-welded section can be deformed or lose its mechanical properties, therefore, prolonged heating has both its advantages and disadvantages.

The gas burner is regulated when the flame is burning normally. So, it is adjusted to the required metal thickness, and only then, the welding flame is activated, after which you can start working. Therefore, one of the most basic tasks of the welder is to determine the required level of the burner to work with this or that metal area. Also, other parameters are taken into account during operation - pressure, distance from the product to the burner, angle of inclination of the flame, and so on, which together gives the use of gas welding.

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