How to weld metal parts correctly

Metal structure welding technology

The most well-known method of joining metal parts is electric welding. It was discovered at the beginning of the nineteenth century by V.V. Petrov. He first proposed the use of an electric arc for soldering metals.

Electric welding is a type of welding that uses an electric arc to melt metal. The temperature of this arc reaches 7000 °C, which exceeds the melting point of any metal.

Description of manual electric welding

The process of welding metals together is quite complex and can only be done by trained specialists. The process is based on the heat of an electric arc. For electric welding you need:

• electrode
• product to be welded (base metal)
• welding transformer
• power supply

Electricity is supplied to the metal being welded and the electrode from a welding transformer. Under the influence of the temperature of the electric arc, the base metal and the electrode melt, forming a weld pool. It remains in a liquid state for some time.

The electrode metal is mixed with the base metal, and the resulting slag floats to the surface, which creates a protective film. After the metal hardens, a weld is formed.

To maintain an electric arc, significant energy is required, which is obtained from direct or alternating current sources.

According to the degree of mechanization of the process, electric welding is divided into:

• manual arc
• semi-automatic arc
• automatic

This parameter depends on how the ignition is performed and how the arc length is maintained, as well as how the electrode is manipulated to give the seam the required shape. In this article we will consider manual arc welding. All operations with this method are performed manually by a specialist (without the use of machinery).

Types of inverters

An inverter is a device for electric welding that greatly simplifies working with metal. This is a modern type of transformer. With the advent of inverters, it has become possible to make connections that previously would have required bulky and complex units. The electricity required for its operation is directed exclusively to maintaining the arc.

Since the inverter is an electronic welding machine, the main load falls on the electrical network (voltage from 220 to 380 W). The principle of its operation is to shift the phase of voltage and increase the shift of current and frequency. First, the inverter changes alternating current to direct current, then it turns it into alternating current again, but with a reduced voltage and increased current and frequency.

How to choose an inverter for a novice electric welder?

A good inverter is distinguished by the presence of a fan. Of course, this helps cool the device and protects against overheating. But the downside is that dust sticks. So you should not buy inverters with the most powerful fans. They will accumulate a large amount of dust inside. In any case, it is necessary to clean the inverter occasionally.

Since the operating principle of the device is based on converting electric current and keeping it in the desired range, an important indicator when choosing will be the built-in element that protects against voltage surges. The optimal level of protection would be 10-15%.

It is also worth paying attention to the temperature range of use. If you plan only for household use, then there is no point in overpaying for the European standard EN 60974-1, which allows operation at temperatures from -150 to +150°C.

A conventional inverter will be adapted to operate between 0 and +30°C.

Another indicator of the inverter's performance is its uptime. For example, a household unit is capable of welding for half an hour followed by an hour break. Industrial devices are designed for long shifts with short breaks.

When choosing an inverter, you should also pay attention to the voltage range. It shouldn't be too big. The best option is if it is indicated that the device will operate at 220 - 230 V. If the lower limit is less, this indicates low performance at low voltage.

What are the types of electrodes?

A welding electrode is a metal or non-metallic rod that supplies current to the work being welded. There are more than two hundred brands, half of which are intended for melting during manual arc welding.

Electrodes can be metallic or non-metallic (always non-melting). Metal ones are divided into:

• non-consumable (from refractory metals such as tungsten)
• melting (from welding wire).

In accordance with GOST, consumable electrodes for manual arc welding are classified according to many indicators, such as:

• the most common classification of welding electrodes is by purpose (for welding low-alloy and carbon steels (denoted by the letter U), for alloyed structural steels (letter L), for alloyed heat-resistant steels (T), for high-alloy steels (B), for surfacing surface layers with special properties (N))
• by coating thickness (thin, medium, thick, extra thick)
• by type of coating (acidic, basic, cellulose, rutile, mixed and other types)
• according to permissible welding position
• by polarity and type of welding current

There is only one answer to the question “which electrodes are better”:

It should be remembered that there are no universal electrodes. They must be selected each time, based on the materials and specific working conditions!

Electrode brands can be found here. Electrode markings are written on the packaging box.

How to properly weld metal structures by welding

Before starting work, the area to be welded is cleaned with sandpaper or a grinder. Next, you need to secure the workpiece (welded part) well.

When starting work, the first thing you need to do is select the electrodes and set the current strength. The diameter of the electrodes is usually 3.2 - 4 mm. You need to measure the thickness of the workpiece. To weld a workpiece made of thin metal up to 3 mm thick, use a 3.2 mm electrode and a current of 90 A. If the workpiece is from 3 to 4 mm, use a 4 mm electrode and set the current to 120 A.

The beginning of welding work is the formation of an arc between the electrode and the surface of the part being welded. To do this, the holder is passed along the surface of the workpiece at an angle of about 60 degrees until characteristic sparks appear. After which, the electrode rises above the surface by 5 mm. An electric arc should form between the electrode and the part being welded.

It must be maintained throughout the entire process and not change in size. During the work process, the coated consumable electrode itself melts under the action of an electric arc, thus the distance between the end of the electrode and the surface of the workpiece increases, the welding current drops and the arc disappears.

To prevent the arc from disappearing, the electrode must be constantly brought into the melting zone at an equal speed, and the 5mm gap between the electrode and the surface to be welded cannot be reduced.

The next stage is the formation of the weld seam. The resulting arc is directed to the area where work begins and melts the metal. The weld is formed by slowly and evenly moving the electrode along the welding line. Depending on the method of moving the electrodes, the seams are divided into:

When forming the correct seam, the electrode must be directed at an angle of 70-80 degrees to the surface of the product in the direction of the welding line and strictly at an angle of 90 degrees in the direction from it.

Advantages and disadvantages of electric welding, alternatives

Let's look at the clear advantages of manual arc welding:

• welding in all spatial positions
• Possibility of welding in places with limited access
• relatively quick change of welded materials
• Thanks to a wide selection of electrodes, welding of various steels is possible
• simplicity of technology.

However, this type of work also has disadvantages:

• harmful conditions during the process
• the quality of seams greatly depends on the qualifications of the worker
• low performance

An alternative to electric welding is forging. However, this is a painstaking process that requires great skill. Detachable connections (bolts, screws) are also used. If it is necessary to connect metal, but welding is impossible, then they resort to rivet joints. It is also non-detachable.

Gas blowtorches are used to join dissimilar metals. The flame soldering method differs from welding in that it does not melt the base metal, but only heats it to a very high temperature. This provides certain advantages: the ability to repeatedly separate materials without compromising their properties. Also a plus is that you can connect smaller parts than by welding.

Warping effect during welding

As a result of uneven heating, cooling and shrinkage of the metal during welding, stresses arise in it. These stresses can lead to deformations and reductions in the strength characteristics of the seam.

To reduce this effect during the welding process, a copper plate is placed under the intended seam. It serves to remove excess heat.

To reduce the effect of metal warping after welding, a method is also used when sections are welded in such a way that the deformations are approximately equal in magnitude but opposite in direction.

Measures to reduce deformation during welding:

• rationalization of the welded joint
• Allowance for shrinkage according to the shape and size of the product
• streamlining assembly and welding preparation
• correct choice of welding method
• heating of the product at all stages of operation
• forging the weld area
• mechanical straightening
• thermal straightening
• general heat treatment

High efficiency in the fight against corrosion is achieved by tempering steel products (a type of special heat treatment of steel).

So, we are convinced that manual arc welding is an effective and very popular method of joining metal parts. Knowing all the nuances of choosing an inverter and electrode, you will be able to implement any weld. Of course, it takes practice and professionalism to do it well.

Source: http://www.m-deer.ru/samodelkin/tehnologiya-ruchnoj-elektrosvarki-metallov.html

Welding of hardened metal – Machine tools, welding, metalworking

Proper metal welding technology is an essential requirement when working with iron structures. Experienced professionals are capable of making a variety of patterns, decorative details and complex metalwork.

To work with an electric welding machine, you must have some experience and practical knowledge of how to weld metal correctly. This allows you to extend the service life of the iron product.

In everyday life, this device helps to correctly connect pipelines, various profiles or small parts. Our material provides detailed instructions on how to weld metal using electric welding.

Basics of electric welding

Electric welding is an electrical device that, through exposure to high temperature and special electrodes, helps connect metal parts to each other.

It is possible to melt the electrodes using an electric arc. It is formed between the surface and the connecting element during the supply of high power direct current.

The design of a modern electric welding machine includes:

• invector;
• transformer installation;
• special three-core cable;
• electrode holder.

The invector is designed to regulate the supply of direct current. During operation, it begins to transform into a permanent one. The transformer installation is responsible for the required welding current power.

In addition, it allows you to adjust the strength of the electric current depending on the type of metal, electrode and thickness of the workpiece. Power varies from 30 A to 410 A.

An electrode is a metal blank made of micro-iron chips with a complex of mineral compounds. The most common diameter is 3–6 mm. The surface of the product is coated with a special solution - coating.

The electrode length reaches from 300 to 550 mm. During the work process, the coating begins to burn and acts as an inert material, which provides better fastening of the metals being welded.

The coating shell contains:

• nickel;
• manganese;
• small iron shavings;
• alumina;
• magnesia;
• limestone.

All these components are highly flammable. The combustion products form a strong iron alloy that is capable of joining any thickness of the metal being welded.

Electric welding process

Many novice welders ask the question: “How to weld thin metal?” Before starting the work process, you need to prepare the appropriate tools and materials:

• electric welding machine;
• set of electrodes. For welding thin metals, a diameter of 4 mm is used. During operation, it is important to calculate the correct AC power. If it is too high, then holes and microcracks may appear on the surface of the iron sheet;
• hammer;
• protective shield;
• Bulgarian;
• sandpaper with a hard texture;
• product template;
• special screws.

The sequence of the welding process is as follows. As a detailed example, pay attention to the photo that shows how to weld metal:

The required electrode is installed on a special holder. Next, connect the positive pole and gradually supply electrical energy.

After this, an electric arc begins to form in the gaps between the electrode and the metal workpiece. It is capable of melting any iron surface while gradually forming a strong metal seam. Next, they begin to connect the parts to each other.

During the combustion of the coating, a gas cloud appears. It allows you to protect liquid iron from direct interaction with oxygen.

When the chemical reaction ends, an impregnation of oxidized metals will appear on the surface of the seam. It further helps protect it from the effects of climatic conditions.

As the joint cools, crystallization of the metal is observed. It provides a strong connection between the workpieces.

Type of welding seam

Experienced electric welders distinguish three types of welding seam. Each of them has its own characteristics and differences. These include:

Threaded. It is performed in the longitudinal direction. The width of such a seam is from 2 to 4 mm. This type of connection is used during rough work for short-term connection of workpieces;

Double. It is considered a more reliable and high-quality fastening of metal parts. The electrode moves in the longitudinal and transverse directions;

Triple. It is used to connect pipelines and complex metal structures. It ensures reliable adhesion of iron parts to each other.

Photo instructions on how to weld metal

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Source: https://stanki-info.com/svarka-kalenogo-metalla/

How to weld parts correctly

Today, welding is the most popular, simple and reliable way to connect metal parts. To do this, you need to have knowledge and practical skills on how to use welding.

To understand how to weld properly, you first need to go through the theoretical part, and then begin to develop practical skills. This process is not complicated, but it is necessary to become familiar with many aspects before mastering the practical aspects of this process.

We will teach you how to use a welding machine to get a perfectly straight and correct seam, even if you have never encountered one before.

Before learning how to weld, you need to understand the essence of how a welding machine works.

It is as follows: a unit connected to an electrical network provides a powerful welding current, under the influence of which an electric arc of high temperature is created between the conductor and the part that needs to be welded.

Under this heat, the metal melts and a bath is formed - a melt area. At this moment, the parts are connected to each other and, when they cool, they form a strong and durable monolithic connection.

Due to the fact that do-it-yourself welding work is simply irreplaceable in construction, during repair work and simply in everyday life for repairing any iron parts, you must remember that there are several technologies for working with welding:

• manual arc technology, which is implemented using special conductors - electrodes. These are small pieces of metal coated with a chemical coating that creates an electric arc. The advantage of this type is its simplicity. Even a novice welder will figure out how to learn to work with such a machine. It does not require the use of gas cylinders or special skills. It is enough to practice to get a high-quality and beautiful seam as a result. The disadvantage of the arc type of connection of products is that you can only work with stainless and ferrous metals;
• semi-automatic welding technique, which is performed by a machine using a special gas that protects the metal from oxidation, which occurs as a result of the combination of oxygen with the molten material. Such welding work can be done with your own hands both in industrial and at home conditions.

Experts recommend always starting with a manual unit, and when you learn how to make the correct seams yourself, then you can switch to a semi-automatic machine.

Welding equipment

Do-it-yourself welding work cannot be done without the help of special equipment - a welding machine. There are several types of them, depending on the technology the master is going to use to weld:

1. A welding transformer is considered the simplest type of equipment that can be used to weld metal. It operates on 220 V (sometimes 380 V). During operation, it converts the voltage to lower frequencies, thereby increasing the current strength. Transformers are very easy to use, do not require super-skills to use them, and allow you to quickly and efficiently create a monolithic connection of metal parts. Among the disadvantages, it can be noted that the arc often breaks down and drops of hot metal splash. Also, sometimes it is difficult to weld metal on such a machine due to the fact that it directly depends on the voltage and senses every jump. But besides this, it is worth noting that the device itself is mobile and compact and is ideal for use at home.
2. A welding rectifier is equipment that provides a stable voltage regardless of the network and guarantees a constant arc, thanks to which the seams are more accurate and the work happens faster, since you do not have to constantly restore the inert environment. Rectifiers are massive and large in size. You can use such a unit to weld metal at home or in industrial applications.
3. The welding inverter is another representative of the devices. It is considered the best, reliable and in demand. When welding with an inverter, you should not be afraid of voltage drops, since it itself transforms 220V and provides a constant, even flow of energy. Accordingly, ideal connection paths are obtained. The inverter has many advantages that are worth mentioning for those who want to learn how to weld iron products correctly:

• withstands voltage surges;
• economically consumes eclectic energy;
• cooking with an inverter is much easier and faster;
• It turns out to be more accurate to weld parts, since there is no spattering at all.

You can learn how to use welding using any type of equipment. The main thing is to follow all the rules of working technology and not forget about safety.

What to look for when choosing a welding machine

Before you learn how to weld with a welding machine, you need to choose it and it is advisable to give preference to a good model that will be easy to learn and then work on. When choosing a unit, you need to take into account some nuances on which the quality of the seams depends:

• welding current is an indicator on which power and efficiency depend. To perform welding work with your own hands at home, up to 200 A is enough;
• resistance to fluctuations in electrical networks. The acceptable interval is +-20%. Others are of poor quality. How to learn to operate a unit if the electricity constantly “knocks out” or the arc disappears? Therefore, this parameter is very important;
• The power of the equipment varies. It’s worth starting from the area of ​​its application. To weld metal at home, a simple or semi-professional machine is enough. For production purposes you need a professional;
• PV – duration of switching on. This is an indicator that determines the time frame for the operation of the unit. On average it is about 40%. That is, after a minute of working on the welding machine, he needs a minute and a half of rest.

In addition to the device itself, you need to select components for it - clamps, wires, pliers, etc. And, it is important to remember that welding with your own hands requires a special form for the master. The welder must protect his face and eyes, as welding sparks negatively affect vision and can cause retinal burns. Be sure to carry out the work with special gloves so that when doing welding work with your own hands, you do not harm your health.

Welding process technology

When everything is ready - the workplace, equipment and preparations have been made, you can begin the practical part, how to weld.

The welding technique is actually simple. The whole process involves exposing the metal to high temperatures. In this case, an electric arc is formed between the material and the electrode element. Thanks to it, melting occurs.

Often welding errors occur due to the inability to hold the arc. Then the melting occurs unevenly. The result is a rough and uneven seam.

A weld pool is a molten mass of metal mixed with conductor particles. To protect the metal from oxidation, a gas cloud appears above the bath and protects it. If the process occurs using a semi-automatic device, then a special cylinder with protective gas is used. When the electric arc is removed, the metal instantly solidifies and a small track remains, which monolithically holds the two parts together.

Advantages of manual arc welding:

• a variety of electrodes allows you to make different seams on different elements;
• the units are not large and can be easily transported;
• just learn how to make a seam;
• ideal for home use.

Along with the advantages, there are also disadvantages:

• release of harmful substances into the air;
• not all metals can be soldered in this way;
• The quality of work will depend on the level of skill of the welder.

For a more detailed introduction to manual arc welding, you can find out here.

Welding with electric welding using gas is a little easier, but before the process itself you need to set up a semi-automatic machine:

• You can determine the current strength from the instructions;
• adjust the automatic wire feed speed;
• set voltage and current;
• check the settings on a rough version of the part.

To work with welding in semi-automatic mode, it is necessary to firmly fasten the work product. In addition, it is necessary to choose a place for this that fully complies with safety regulations. For example, it is prohibited to use wooden workbenches or tables.

During welding, it is necessary to strictly observe the interval between the conductor and the part - 5 mm. If you do not disturb it, the seam will turn out almost perfect. There is no need to rush, the electrode burns out smoothly and the master has time to form a high-quality track.

If the arc goes out all the time, it is necessary to increase the current on the unit itself.

Source: https://crast.ru/instrumenty/kak-pravilno-svarivat-detali

How to properly weld metal

Metal welding allows you to connect various parts and create complex structures. It is used in the construction of bridges, buildings, laying pipelines, and creating complex parts. Parts can be welded together not only at a special enterprise, but also far from cities and power lines.

The method of joining parts by welding is mastered by professionals and amateurs. In garages and sheds, craftsmen bring their ideas to life, repair various mechanisms, and make things useful for the household.

How to cook properly

From the outside, welding work is not difficult. However, experienced metal welders recommend first studying the theory and practicing on unnecessary things, and only then getting to work.

It is not enough to connect 2 pieces of iron together. Such a seam will burst at the first blow. It is important to learn how to weld metal so that it does not lose its characteristics. Only a properly heated bath and the melts of the edges of the parts mixed together can form a strong, hermetic connection.

Work technology

There are about 100 types of metal welding. The technology of electric arc welding with electrodes, wire, and plates is mainly used.

Welding technology involves heating the metal to a liquid state and then mixing it. To connect different parts, molten wire or the electrode itself is used.

Types of Welding Machines

Based on productivity and power, welding machines can be divided into two types: household and industrial.
Parts up to 5–6 mm thick can be welded first. Industrial equipment can operate for a long time without stopping. How to choose the right welding machine?
Lesson 1 Welding of metals occurs by heating to high temperatures. Melting is achieved in various ways. Each of them has its own equipment. It is divided into groups according to the principle of operation:

• transformers;
• inverters;
• rectifiers;
• TIG devices;
• semi-automatic;
• spotters.

In addition, devices are used for gas processing of metal workpieces, cold welding, which creates high pressure, and other types of joining parts.

Transformer

Classic welding machines were the first to be invented. They simply lowered the voltage, leaving it variable. The power transformer reduces the network voltage to no-load values ​​- 50–60V. By setting operating parameters, the following types of equipment are distinguished:

• thyristor - phase adjustment;
• with magnetic dispersion;
• with standard dispersion.

The disadvantage of the device is the unstable arc due to alternating current. Transformers are large in size and have high energy consumption.

Inverters

Inverters create optimal conditions for metal welding. They equalize alternating current and make it high-power, regulated with great precision. Inverters operate from a consumer network of 220V with a frequency of 50 Hz, industrial at 380 V. During the conversion process, the current passes:

• network rectifier;
• a frequency converter;
• high frequency transformer;
• power rectifier.

Inverters are configured to work with forward and reverse current. They work with electrodes of any type, welding high-alloy ferrous and non-ferrous metals. They have protection against power surges. Suitable for training beginners because they have a stable arc.

To work with direct current, rectifiers are also used, which consist of diodes and semiconductors. They convert alternating current into direct current and allow you to regulate its value. They do not have fine tuning.

All other types of welding equipment are various versions of the transformer and inverter.
How to choose a welding inverter for your home. Review from a welder.

Step-by-step instructions for welding work

Before starting welding, it is necessary to check the work site for compliance with safety regulations. There should be no unnecessary objects on the site, especially flammable ones, puddles of water, or spilled oil.

The equipment should be checked for serviceability and connected. The stove must be grounded. A clamp with the corresponding current value is attached to the part. The workpiece is prepared for welding if the following steps are completed:

• joints are cleaned;
• the workpiece is installed on an assembly plate or rack and secured;
• the parts are connected to each other by clamps or clamped in a special device.

You should start cooking after fully preparing the place, equipment and tools.
How to learn to weld metal. Tips for beginners, at the request of subscribers

Tools and protective equipment

In addition to the clamp for the electrodes, the welder should always have a thin metal hammer with him to beat off the slag. The seam is checked for lack of penetration, undercuts, and tops. If necessary, the operating mode can be changed.

Welding is one of the harmful and dangerous jobs. Compliance with safety precautions is especially important for novice workers who do not yet have practical skills. When carrying out welding work, you can get various types of damage: electric shock, burns, eye damage, vapor poisoning when flux burns.

Mandatory protective equipment for a welder when working are:

• mask;
• mittens or gloves;
• pants and jacket;
• work boots;
• tarpaulin.

A mask with dark glass protects the eyes from the blinding light that occurs during welding. Gloves and a suit made of non-flammable materials protect the skin from metal splashes and sparks.

Protective equipment or what do the pros neglect when welding?
Lesson 7 + announcement of the 2nd part of the video course. When working outside an equipped welding station, a worker may need a tarp. He uses it to cover objects that cannot be removed.

For example, a wall and nearby furniture when welding water supply or heating pipes in a house.

Tools and protective equipment

Which electrodes to use

The thickness of the metal and the number of seams applied determine the diameter of the electrode. When welding parts of large thickness, the root seam is laid with a thin electrode of 2–3 mm. In the future, four are used. When the sheet thickness is more than 20, it is possible to use an electrode with a diameter of 6 mm.

For welding structures made of low-alloy steels, coated electrodes of the following grades are used: UONI, OZS, ANO. They are widely used in the creation of building structures, when laying pipelines and welding other parts that have high demands on the strength of joints.

When welding high-alloy and carbon steels, experts recommend using chromium-nickel electrodes grade EA 395.

High-quality welding of non-ferrous metals is carried out using rutile electrodes of the MP 3C series. Tungsten non-consumable grades WC 20 are suitable for joining parts made of non-ferrous metal alloys.

Chromium-nickel and rutile electrodes are recommended for learning the welding process.
They light easily and hold the arc well. How to choose the right electrodes? Lesson 6

Electrodes with rutile and other special coatings are considered universal. They can operate on any current, the seam lies horizontally. Vertical only from bottom to top. Metal spattering is minimal. After them, it’s difficult to switch to UONI and other brands, but only after mastering classic electrodes can you become a welder.

Preparation

Before starting work, you should prepare the metal for welding. The surface of the workpiece must be cleaned of dirt, oils, and rust. Oxide films are removed chemically immediately before welding.

If the seam thickness exceeds 3–5 mm, you should cut the edges on the machine, removing them at an angle of 45⁰.

The parts to be welded are connected using clamps. For mass production, special devices may be used.

Cleaning the joint

Connection

Before work, check the condition of the equipment and grounding. A 0 or a minus is then connected to the part, depending on the type of current being applied. The equipment is connected to the network and modes are configured. After this, the electrode is inserted and the welding machine is turned on.

Welding process

Before cooking, the device is adjusted to the desired operating mode in accordance with the thickness, material of the part and currents recommended for the electrodes. After this, you can proceed directly to welding.

1. Light the arc.
2. Heat the weld pool.
3. Use an electrode to move the molten metal along the seam, ensuring the edges are connected.

During work, you should ensure that the flux does not remain in the seam, but melts and floats up.

What errors might there be?

Incorrectly selected current - if its value is low, the arc will constantly go out and the seam will be interrupted. A high current value leads to penetration, burning through the body of welded metal structures.

The slag output is controlled by the angle of inclination of the electrode and depends on its type. If the bath moves quickly, slag inclusions remain in the seam.

High-alloy steels must be heated before processing, otherwise the edge material will not have time to melt or a transition zone will form.

Welding of non-ferrous metals must be carried out with special electrodes in a shielding gas environment.
The polarity of the current must be straight in order for the metal coated with oxides to melt. 5 main mistakes of a novice welder.

What can be made

Welding is used to connect product elements made using cold forging. The result is openwork fences, uniquely beautiful garden furniture and other metal crafts. Craftsmen turn old bolts and nuts into charming animals and sea monsters.

Source: https://metalloy.ru/obrabotka/svarka/metalla-tehnologiya

How to properly weld metal with an inverter for beginners

It's no secret that many people learned to weld on their own. There are really a large number of such people, and many of them can use the practical skills acquired at home with high efficiency.

However, sometimes it is better to gain some theoretical knowledge first before getting down to business.

Let's talk about what welding is for beginners, how it is characterized, and why it is best for beginners to use an inverter.

Briefly about welding inverters

Inverter – electronic welding machine. Quite accurate, economical and easy to use. The main load during operation falls on the welding network. The advantages of an inverter, especially for beginners, are that they have storage capacitors.

They are necessary to collect a certain amount of electrical charge, which ensures uninterrupted operation. Many people have probably noticed that when working with old welding machines, the voltage in the network begins to jump sharply. Under such conditions, any household appliance may burn out. So, with inverter welding there is no such drawback.

In addition, a smooth arc start is ensured, which is necessary to ensure the quality of the seam.

When connecting metal parts, a huge number of processes take place. Most of them are hidden from human eyes, while others are obvious. Thus, the welding process itself can be divided into several simple stages. At the first, an arc is formed, which indicates a short circuit between the electrode and the metal.

At the second stage, a high temperature is created (up to 7 thousand degrees), which allows you to melt any metal. As a result of melting of the electrode and the edges of metal products, a connection occurs - a weld is formed. This concludes the process. The electrode plays a big role. It consists of an alloy, on the surface of which a powder composition is applied.

The powder is used to maintain uniform arc burning, and the electrode itself is necessary to form a weld pool without oxygen.

Before you begin the work, you will need minimal ammunition. Thus, it is not recommended to carry out work without a special protective helmet and rough gloves. Well, in addition to this, it is advisable to have an old jacket made of coarse cotton (for example, denim) fabric that will not burn from a spark.

Next, you need to adjust the welding current and select the correct electrode. Products with a diameter of 2-5 mm are suitable for inverter welding. The welding current is set based on the thickness of the workpiece and the material. To avoid sticking, the electrode is brought smoothly to the surface to be treated. After this, you can connect the ground terminal to the part.

The welding process begins with ignition of the arc. The electrode is brought to the surface at a slight angle. To activate it, you need to touch the surface to be welded several times. During operation, the electrode must be kept at a distance of its diameter from the surface. In principle, welding with an inverter is quite simple for beginners. Now let's move on.

Gap control

The arc gap is of great importance during welding work. This gap is the distance between the electrode and the metal, which is formed during welding work.

If the distance is insufficient, the seam will turn out convex, since the metal at the joint will not have time to warm up. If the gap is too large, this will lead to an unstable arc, which, in turn, can lead to poor weld quality.

In particular, the connection turns out to be crooked.

For good penetration and a high-quality seam, it is necessary to choose the optimal gap. We can safely say that learning to maintain a constant correct distance is the most difficult skill.

But if you learn how to do it, arc welding for beginners will soon turn into welding for professionals. Do not forget that during the process the electrode gradually melts, therefore, if you do not move it, the gap will increase.

Watch this more carefully and everything will be fine.

Forming the correct seam

I would like to note that semi-automatic welding for beginners involves not only maintaining the required gap. There are several more important requirements that it is advisable to comply with:

• speed and trajectory of the electrode;
• current strength;
• angle of inclination of the electrode.

Welding techniques change when working with different materials. That is why in some cases the electrode is led quickly, in others, on the contrary, slowly. In this case, the thickness of the metal being connected affects the current strength. The thicker the product, the more current must be supplied to the electrode.

And the thickness of the seam and weldability depend on the angle of inclination of the electrode. All this must be taken into account when performing work. In principle, manual welding for beginners of simple parts is within the power of everyone.

Experience will come only if you constantly practice and train, creating increasingly complex seams.

About polarity when welding

It is necessary to understand that there is direct and reverse polarity. If we are dealing with the first, then the heat input into the metal product increases. Consequently, a narrow but rather deep melting zone is formed. This technology is used for precise processing of fairly thick sheets.

If you need to create a high-quality seam on a thin sheet, then reverse polarity is used.

It is characterized by the fact that there is a reduced input of heat into the product, therefore, the seam is wide, but not too deep. Currently, both technologies are actively used.

It is quite possible that at the beginning of the journey it does not make sense for a novice welder to understand polarity, but after making some connections this knowledge will come in very handy.

Manual arc welding for beginners: working with thin sheets

As noted a little above, thin metal products must be worked with reverse polarity. This is due to the fact that they are quite easy to burn through, which will ruin the workpiece. Reverse polarity is installed directly on the inverter. At the same time, the current strength also decreases to normal.

In this case, the electrodes are connected “plus” to the inverter, and “minus”, respectively, to the metal sheet. This will allow you to get high quality seams and not burn through the sheet. However, if you are a beginner, then you need to choose a workplace so that the seam is visible to you. In this case, you will be able to control the process.

Over time, you will perform the work automatically, but this will only come with more experience.

This is due to its exceptional ease of use. The line includes models that are more suitable for amateur welding, and there are expensive professional inverters. The last option is unlikely to suit a beginner.

Such equipment is more often used in industry.

Of course, if you are going to work as a welder, then you will need an inverter for professionals. It costs a lot, of course, but allows you to perform welding work with a wide variety of materials. Don't forget about personal protective equipment. You cannot look at the arc without special glasses or a mask.

Firstly, this makes your eyes very tired, and secondly, it negatively affects your vision. This is why it is imperative to use a mask. In principle, this is all that can be said about inverter welding for beginners.

There is nothing complicated here, but it is necessary to strictly follow the technology, and then the seam will be durable and of high quality.

Source: https://steelfactoryrus.com/kak-pravilno-svarivat-metall-invertorom-dlya-novichkov/

How to weld metal using inverter welding? — Metals, equipment, instructions

Many home craftsmen are interested in how to learn how to weld with a welding inverter from scratch . There are no special secrets; if you take a household or semi-professional class welding inverter, it is not so difficult to do. All you need is patience, accuracy and following the recommendations of experienced welders.

Principle of operation

A welding inverter for manual welding converts the mains voltage (220 or 380 to 50 Hz) into a voltage suitable for maintaining the electric arc. This transformation takes place in three stages:

• AC input voltage is rectified,
• this direct current powers the high-frequency generator, it creates alternating current with a frequency of 20-50 thousand Hz.,
• the transformer reduces the voltage to 70-90 volts, the current in the working winding reaches 100-300A.

Triple conversion makes it possible to reduce the size and weight of the device several times compared to conventional welding transformers . In addition, thanks to automatic adjustment of electronic circuit parameters, the device provides high stability of output current and voltage. The inverter is not affected by voltage surges in the supply network, and it itself does not cause such surges.

In semi-professional and professional models, systems are also installed that facilitate ignition of the arc and prevent sticking of the electrode.

The operating current flows through a circuit formed by:

• electrode and mass cables,
• electrode,
• electric arc in the air gap,
• workpiece

The electrode wire is connected to the holder, the ground wire to the cleaned area on the part.

Design

The design of the inverter for welding is quite complex , this is explained by its wide capabilities and ease of use. The device consists of:

• frame,
• control panel with current regulator, mode and parameter indicators,
• chassis,
• carrying handle, compact models are equipped with a shoulder strap,
• electronic circuit of the inverter voltage converter,
• fan for cooling,
• network cable,
• welding wires.

Household models weighing 5-7 kg are capable of developing a welding current of up to 120-150 A; they can easily be carried on the shoulder. Such devices can weld steel up to 4-5 mm thick.

More powerful models of welding inverters can produce a current of up to 250 A, they can already be carried by the handle - the weight is up to 20 kg. Welding for dummies is best mastered using an inverter.

Safety precautions

To ensure that learning how to use an inverter welder does not end sadly, you need to know how to weld using inverter welding correctly and safely. Be sure to use protective equipment .

The welding location must meet the following requirements:

• there is an insulating flooring or dielectric mat,
• protective metal screens have been installed to protect against the scattering of molten splashes, as well as sparks during welding and stripping,
• high-quality lighting is provided,
• exhaust ventilation is installed to remove welding gases,

Important! It is strictly unacceptable to clutter the work area; only the workpiece, equipment, welding machine and welder should be in it. It is also prohibited to place flammable materials within a radius of 5 m from the welding site.

Basics

Inverter welding for beginners is much easier to master using an inverter than using an outdated transformer or rectifier. To learn to cook, it is better to take waste ferrous metal of average thickness - 2-5 mm, and in the first lessons master simple straight seams in the “top” position, butt and overlap .

When simple techniques on how to weld with an inverter are mastered and begin to be obtained with constant quality, you can move on to mastering more complex lessons: welding vertical and inclined seams, welding thin sheets, multi-layer welding of parts of large thickness and others .

Polarity

Direct polarity means connecting the electrode to the “-” connector, and the workpiece to the “+”. In this case, electrons move from the electrode to the workpiece. The heating of the metal is more intense, the melt area is narrow and deep. This connection is used when working with workpieces of large thickness, as well as for cutting metal.

Reverse polarity means that "-" is connected through the clamp to the workpiece, and "+" is connected to the electrode. Electrons move from the part to the electrode, the melting area becomes smaller and wider. This reduces the risk of burning thin-sheet workpieces

Electrode feeding speed

The speed of movement of the electrode is selected so that a sufficient amount of melt enters the working area to form the suture material. If you move the electrode too quickly, the metal will not have time to warm up, and the seam will turn out to be small, the so-called “lack of penetration.”

If the speed is insufficient, the metal will overheat, the consumption of welding materials will increase and the risk of burn-through and deformation of a workpiece of small thickness will increase.

Current strength

This parameter is selected depending on the thickness of the workpiece and electrode according to the table.

A higher current increases the depth of metal penetration, and the electrode can be driven faster. If the optimal values ​​are exceeded, overheating of the metal and burn-through are also possible.

In practice, the exact value is selected taking into account the configuration of the product and climatic conditions.

Workpieces of small thickness are welded with reverse polarity current , using the method of guiding the electrode at an angle forward. The diameter of the electrodes needs to be chosen smaller.

Particular care must be taken when igniting: at this moment it is easy to burn the sheet.

At the end of the seam, do not sharply lift the electrode - a crater may form. To ensure that a thin part does not move during welding, it should be securely fixed in the equipment or grabbed after 10-15 centimeters by spot welding.

How is the seam formed?

An electric arc melts the metal at the edges of the workpieces being joined. The melt area is called the weld pool . The molten metal of the electrode core enters it from above. When the electrode is moved along the seam, the electric arc and the weld pool moves after it, and where the arc leaves, the metal cools and crystallizes.

Preliminary preparation

How to learn how to weld Resanta well yourself? First of all, you need to qualitatively prepare the workplace, materials and equipment. The strength and durability of the seam directly depends on the quality of preparation. It is necessary to work with electrodes that are suitable in material and thickness for the workpieces being welded. Conformity tables are provided in welding manuals .

Means of protection

To avoid injury during electric arc welding, you should:

• use work clothes made of non-flammable fabric,
• clothing must completely cover the skin,
• use strong welding gloves,
• shoes made of thick leather with reinforced soles and steel toes must have a high top, trousers worn over the shoes,
• Be sure to use a welding mask with automatically darkening glass.

Workplace

The workplace must be prepared so that it is comfortable and safe . The workpieces must be firmly fixed to the work table. For large sizes, they are laid out on a flat, dry base and securely attached to each other. All flammable materials within a 5 meter radius must be removed, or non-flammable screens must be used.

How to choose an electrode?

What diameter and material of the electrode to choose is determined based on the material and thickness of the workpiece. Recommended values ​​are given in the inverter instructions.

It is better to start training with blanks made of ferrous metal 3-5 mm thick . Electrodes with a thickness of 2.5-4 mm are suitable.

Inverter connection diagram, polarity

The inverter is connected to the electrical network or to a gas generator.

The connection polarity is selected based on the thickness of the workpiece . The place where the ground wire clamp is attached to the workpiece must be cleaned and degreased. If the work table has a large contact area with the part, the mass can be applied to it.

The metal is usually covered with an oxide layer, rust, remnants of old paint and other contaminants. To weld a high-quality seam, they must be removed. Mechanical contamination is removed by cleaning with a metal brush or an abrasive disc.

Oil and grease stains are removed by degreasing by wiping with a rag moistened with a solvent such as gasoline, white spirit, or acetone. This is a mandatory condition, without which a good seam cannot be obtained.

How to work?

A few recommendations on how to properly weld metal with an inverter for beginners will help them master the technology. To begin with, the current strength can be set using table values. Now you can proceed directly to welding.

Ignition of the arc

Arc welding for experienced and beginners begins with igniting the arc. The arc is ignited in two ways:

• striking the workpiece with an electrode
• tapping.

For novice home craftsmen, it is recommended to light an arc using the striking method . The electrode must be brought to the workpiece quickly and removed slowly, at a distance of 2-3 mm.

  Which inverter-type welding machines are better?

How to guide the electrode?

To prevent the heavy cable from turning the holder when moving along the seam, the craftsmen give the following advice: wrap it around your working hand and press it to your side.

The holder must be moved evenly, without jerking or stopping, at the same distance between the tip of the electrode and the workpiece. It is necessary to take into account that as you move along the seam, the rod burns out and its length decreases.

Depending on the characteristics of the seam, several techniques are used to determine the position of the electrode relative to the workpiece:

• forward angle (30-40o) suitable for vertical and ceiling seams, fixed pipe joints,
• right angle (90°) is convenient for hard-to-reach places and joints of rolled profiles,
• angle back (30-40o).

Welding seam for beginners, the “back angle” method is recommended.

Arc gap control

A constant gap between the tip of the rod and the part is very important. It is correct to maintain it within 2-3 mm . As the gap increases, the power of the arc increases, its stability is lost, and the melt begins to splash.

As the gap decreases, the arc power decreases and the risk of lack of penetration and sticking of the electrode increases.

For beginners, it is better to master electric welding with an inverter. If there is no experienced welder who can teach all the basics and subtleties of welding, you can master welding on your own. It is not necessary to purchase a thick tutorial; these recommendations are sufficient.

Source: https://spb-metalloobrabotka.com/kak-varit-metall-invertornoy-svarkoy/

How to learn how to weld correctly: types of welding machines and detailed instructions

Due to the durability and reliability of welding fasteners, there is not a single industrial sector left where this technology is not used.

Owning an electric welding machine will allow you to build any metal structures, from a simple fence in the country to a multifunctional barbecue or an openwork swing in the garden.

Therefore, we will look at how to weld correctly and tell you about all the secrets and nuances of welding technology so that your first seam is neat and durable.

Welding technology

To learn how to weld correctly, you need to know that electric arc welding is the process of attaching metals using an electric arc between an electrode and the surface of the material being processed. The resulting elevated temperature promotes the simultaneous melting of the metal base and the electrode. Moreover, a so-called weld pool appears, where the base metal is connected to the molten electrode.

The volume of the bath depends directly on the shape of the edges of the surfaces being joined, the welding mode, the position of the products in space, the speed of movement of the electrode, etc. and is 7-15 mm wide , about 5 mm deep and 11-32 mm long.

The gas layer that forms when the electrode coating melts does not allow the metal to burn due to elevated temperature; it completely displaces oxygen from the melting area. After removing the welding arc, the metal crystallizes and a common seam of parts appears, protected by a layer of slag, which is removed after cooling.

The main advantages of electric arc welding:

• availability;
• the ability to cook different materials without readjusting the device;
• good performance;
• available consumables;
• excellent seam quality.

The disadvantages of this method include the need to prepare the edges to be welded and the indispensable presence of electricity.

Selection of equipment and materials

Before you start welding, you need to understand that this process is accompanied by the appearance of splashes and sparks of hot metal, a danger to the eyes and the release of toxic gases.

Therefore, in order to cook safely, you need to stock up not only with high-quality equipment, but also with the necessary equipment . To start cooking, you will need:

• welding machine;
• welder's hammer;
• set of electrodes;
• workwear;
• welding mask;
• metal brush.

How to choose the right welding machine

A high-quality welding machine with the ability to regulate the current voltage of 10-200 A can help you learn how to weld correctly. Naturally, you can assemble a simple welding transformer yourself, but in this case you don’t have to think about how to properly weld thin metal, since for This work requires minimum voltage values. Factory devices are divided into:

• Welding inverters. These devices provide many possibilities to cook with electrodes with any optimal characteristics. The electronic components of the inverter system make it possible to adjust the current strength, arc force, ignition speed, etc., this ensures excellent weldability of the parts. In addition, inverters are lightweight and quite compact.
• Welding rectifiers. These devices are equipped with a diode rectifier, due to which the alternating voltage turns into direct voltage, which is required to form an arc. Cooking metal using straighteners is a little easier due to the stable high arc.
• Welding transformers. Used to reduce voltage while increasing current. Being productive and inexpensive devices, they weld metal quite well, but have the disadvantages of large mass, strong voltage drop and an unstable arc.

There is constant debate about which welding method is best for welding. Some welders like the reliability and simplicity of a transformer , some like manual welding with a rectifier. But the most convenient way to learn how to weld is with the help of a welding inverter. The ability to adjust the voltage will make it possible to weld metal correctly literally in the first stages.

How to choose electrodes

For manual arc welding, rod electrodes with protective treatment of the wire are used. The metal of the wire must match the type of materials being welded, therefore different electrodes are used for welding magnesium, bronze or steel metals.

During welding, the protective coating Sometimes coatings have gas-forming additives; during cooking, they release gas, which limits the access of oxygen to the melting site.

As a rule, the question of which electrodes to choose does not arise for beginners, because they most often begin to learn the craft by welding simple low-carbon steels.

The use of welding rectifiers makes it possible to use for such and stainless metals UONII brand electrodes , which are intended for direct current welding.

Electrodes of the ANO brand can be used to work with transformers and rectifiers; they allow you to work with both reverse and direct current, which is why amateurs choose them much more often than UONII.

Taking into account the thickness of the parts being welded, electrodes with a cross section of 1.6-5 mm are used. At the same time, 4-5 mm rods are used for cutting metals, setting the highest current strength.

You can find out the required electrode diameter using tables of the dependence of this parameter on the thickness of the material, as well as using various formulas. Beginners do not often use electrodes with a diameter larger than 4 mm.

Varieties of welding work (butt, overhang, horizontal welding, etc.) almost do not depend on the diameter of the wire, which cannot be said about the width of the seam and the depth of the weld pool.

Due to the fact that the specific welding current directly depends on the diameter of the electrode, the current concentration is higher at the end of a thin wire, therefore the penetration depth is greater than when using a thick rod. In this case, the use of an electrode with a cross-section of 4-5 mm melts the metal not so much, creating a wider seam.

That is, it is difficult to answer which electrode to choose; the correct choice takes into account many nuances, from the type of welding unit to the required seam width.

Selecting current strength and polarity

To properly weld metal, the required current strength is determined using tables or by calculation, and then this value is set on the inverter panel. The higher the current, the deeper the weld pool and the greater the arc power. But there is no need to exceed the optimal value - the metal will burn out and the seam will be of poor quality.

When setting the current strength, be sure to take into account the location of the work. The maximum current value is set for horizontal planes. For vertical seams it is reduced by 15%, and ceiling seams require a reduction in current strength of more than 20%.

If you weld with a rectifier or inverter welding, then the quality of welding is influenced by both the current strength and polarity, namely the direction of movement of electrons.

Electrons move from a negative charge to a positive charge . To cook correctly, the polarity is changed, both forward current is set (product to plus, electrode to minus) and reverse. As a rule, a direct connection is chosen; in this case, the part warms up more, but for welding thin materials, the polarity is changed using an inverter. Reverse polarity is also used for welding alloyed metals that are prone to burnout of easily melting alloys.

Manual welding technique

First try to strike an arc and hold it for a certain amount of time. Then follow the instructions:

• Using a metal brush, you need to clean the surfaces of the fastened parts from rust and dirt. If necessary, their edges are adjusted to each other.
• It is better to learn to weld with direct current, so connect the “positive” terminal to the product, place the electrode in the clamp, and set the required current value on the welding unit.
• In relation to the part, tilt the electrode at an angle of approximately 60° and slowly move it along the surface of the product. When sparks occur, lift the edge of the electrode 5 mm to ignite the arc.
• If the arc is reluctant to ignite and the electrode constantly sticks to the metal, increase the current by 10-20 A. If the rod sticks, swing the handle from side to side, probably even with force.
• Do not forget that the electrode will constantly burn out, so only maintaining a distance of 3-5 mm will make it possible to maintain a stable arc.

Having learned how to start an arc, try to slowly move the rod towards you, while making movements of 3-5 mm to the sides . Try to transfer the melt from the periphery to the middle of the weld pool. Once you have made a seam of approximately 5cm, remove the rod and allow the metal to cool, then tap the joint with a hammer to remove any slag. A high-quality seam has a wavy monolithic surface without inhomogeneities and craters.

The cleanliness of the seam depends directly on the correct movement of the electrode and the size of the arc.

How to maintain an arc

Some recommendations on how to move the electrode and maintain the arc to obtain a quality weld:

• For a wide seam, the electrode is moved across its line, making oscillatory back-and-forth movements. The size of their amplitude determines how wide the seam will be, therefore the size of the amplitude is calculated taking into account specific conditions.
• The longitudinal movement of the electrode creates the fusing of the thread bead; its width is usually several millimeters larger than the diameter of the electrode, and the thickness will depend on the current strength and the speed of movement. The thread bead is the narrowest seam.
• By progressively moving the electrode along the axis, the required arc length is maintained. When melting, the size of the rod decreases, so you need to constantly bring the holder with the electrode closer to the metal, maintaining the required gap.

During welding, a combination of these three movements is used.

Protecting metal from corrosion

If you remember, at the very beginning of the article we talked about the fact that in order to weld correctly with electric welding , it is not enough to just watch the video, but you also need to prepare in theory? Agree that the article provides a better opportunity to learn the theory. In addition, the videos for some reason omit the need to protect parts from corrosion during subsequent use. We will try to remove this defect.

It is no secret that metal under the influence of oxygen quickly undergoes rust formation. Believe me, seams corrode much faster after welding.

To protect metal products from corrosion, painting is usually used. To avoid having to do this kind of work every year, do it according to all the rules.

First, you need to remove rust and old paint . To do this, it is advisable to use metal brush attachments for an angle grinder or drill, but you can also carry out the work with a simple metal brush. Do not forget to protect your eyes with a shield or goggles during this work.

After cleaning the parts, coat them with a rust converter, and then treat them with a layer of primer. Select a primer composition that is specifically designed for working on metal. After this layer has hardened, you can begin painting. Pentaphthalic and acrylic enamels used for external work showed excellent results.

a spray bottle rather than a roller or brush for painting purposes . Using it, you can apply a thin and uniform layer of paint, which over time will not peel off or crack.

Do-it-yourself welding is a rather complex undertaking, but if desired, you can still master it. You just need to learn the basic rules of work and gradually learn to do the simplest exercises. There is no need to waste time and effort on learning the basics, which will later become the basis of mastery. Then you can safely move on to complex techniques, improving your skills.

Source: https://stanok.guru/metalloobrabotka/svarka/kak-nauchitsya-pravilno-varit-svarkoy-podrobnaya-instrukciya.html

How to properly weld metal using electric welding - Women's secrets

In a private house, in a country house, in a garage and even in an apartment - everywhere there are many jobs that require metal welding. This need is especially acute during the construction process. Here, especially often, something needs to be cooked or cut off.

And if you can still cut it with a grinder, then there is nothing to reliably connect the metal parts with except welding. And if the construction is carried out with your own hands, then the welding work can be done independently. Especially in places where the beauty of the seam is not required.

We will tell you how to properly weld by welding in this article.

Basics of electric welding

Welded metal joints are the most reliable today: pieces or parts are fused into a single whole. This happens as a result of exposure to high temperatures.

Most modern welding machines use an electric arc to melt metal. It heats the metal in the affected area to the melting temperature, and this happens over a small area.

Since an electric arc is used, welding is called electric arc welding.

This is not a completely correct way of welding)) At a minimum, you need a mask

Types of electric welding

An electric arc can be formed by both direct and alternating current. Welding transformers use alternating current, and inverters use direct current.

Working with a transformer is more complicated: the current is alternating, so the welding arc “jumps”, the device itself is heavy and bulky. The noise that both the arc and the transformer itself makes during operation is also quite annoying.

There is one more problem: the transformer greatly “stresses” the network. Moreover, significant voltage surges are observed. The neighbors are not very happy about this fact, and your household appliances may suffer.

Inverters mainly operate from a 220 V network. At the same time, they are small in size and weight (about 3-8 kilograms), operate quietly, and have almost no effect on voltage.

The neighbors won't even know you started using the welding machine unless they see you. In addition, since the arc is caused by direct current, it does not jump and is easier to stir and control.

So if you decide to learn how to weld metal, start with a welding inverter. Read about choosing an inverter welding machine here.  

How to learn to cook by welding

It all starts with preparing the workplace. Safety when working with electric welding must be given increased attention: there is a possibility of injury from both electricity and high temperatures. Therefore, take your preparation seriously.

It is more convenient to learn to weld with electric welding on a thick piece of metal: it is better to practice on it. In addition to it and the welding machine, you will need gaiters (thick gloves) and a welder’s mask.

You also need thick clothing that protects the entire body, and durable shoes with thick leather. They must withstand sparks and scale. You will also need a hammer and a wire brush to knock off the slag.

You will need glasses to protect your eyes.

How to connect the electrode

It will be easier for beginners to carry out welding work if they take a universal electrode with a diameter of 3 mm (3.2 mm, to be precise). They are more expensive, but easier to work with. After you learn how to weld metal, you can try using cheaper ones, but it’s better to start with these.

The electrode is inserted into a holder attached to one of the welding cables. There are two types of clamps - spring and screw.

If the electrode holder is spring-loaded, press the button on the handle and insert the electrode into the socket that appears. When screw clamped, the handle rotates. Unscrew it, insert the electrode and clamp it.

In any case, it should not wobble. After installing the electrode, you can connect the cables.

There are two outputs on a DC welder: positive and negative. There are also two welding cables:

• one ends with a metal clamp-retainer - it is connected to the part;
• the other is a holder for the electrode.

Which polarity to connect for welding depends on the type of work. If we talk about inverters, then more often the plus is connected to the part, and the minus is supplied to the electrode. This connection option is called direct polarity. But there is a list of works in which reverse polarity is applied: minus to the part, plus to the electrode (for example, for welding stainless steel).

Direct and reverse polarity of connection on the welding inverter

Straight polarity provides better heating of the metal, which is necessary for most connections. This is explained by the fact that electrons move from the negatively charged pole - with straight polarity, this is the electrode - to the positive - part. At the same time, they additionally transfer their energy to the metal, increasing its temperature.

We figured out how to connect the electrode to the inverter. Now about how to light an arc. It occurs when there is direct contact between the electrode and the part. There are two ways:

Everything is clear from the name: in one case, you need to run the electrode along the seam (so that there are no marks left), in the second, you need to hit the part with the tip of the electrode several times.

When the electrode is new, its tip is exposed, ignition occurs easily. If it was already in use, a wall of several millimeters of protective coating would form around the rod. This coating needs to be knocked off by hitting the part with the tip several times.

Both methods of ignition are used, here everyone chooses what is convenient for them. This skill is the first one you will have to master if you want to learn how to use electric welding.

Therefore, you take several electrodes, a thick piece of metal, and try to strike an arc. Once you have succeeded, you can proceed to the next stage of training.

Electrode tilt

The main position of the electrode is tilted slightly towards you - at an angle from 30° to 60° (see figure). The amount of inclination is selected depending on the required weld and the set current. Focus on the condition of the weld pool.

The first position is called the “backward angle.” In this case, the bath and molten slag moves behind the tip of the electrode. Its angle of inclination and speed of movement must be such that the slag has time to cover the molten metal. In this position, we obtain heating of the metal to a greater depth.

Manual arc welding technique: positioning the electrode at an angle forward and at an angle backward

There are situations when the metal does not need to be heated very much. Then the angle of inclination changes to the opposite, the seam and the bathtub “stretch” behind the electrode. In this case, the heating depth is minimal.

Electrode movements

The answer to the question “how to properly weld with electric welding” is simple: you need to control the weld pool. To do this, it is necessary to hold the electrode at a distance of 2-3 mm from the metal surface and control the condition and size of the weld pool. This is where the skill of a welder lies.

The difficulty lies in the fact that several parameters have to be controlled simultaneously:

• move the electrode along one of the trajectories shown in the photo,
• as it burns, lower it a little lower, maintaining a constant distance of 2-3 mm;
• monitor the size and condition of the weld pool, accelerating or slowing down the movement of the electrode;
• follow the direction of the seam.

The movements of the electrode tip are shown in the figure. Those who want to learn electric welding for home use do not need to master all of them, but you will need two or three movements: for different situations, seams and metals.

Another element of manual arc welding technique: the tip of the electrode must move along one of these trajectories (or something similar)

How to learn to cook with electric welding? Practice movements on a thick piece of metal. Then you get not seams, but rollers. This stage is the initial one. On it you will master the basic skills of a welder: learn to control the distance from the tip of the electrode to the part, and at the same time, move it along a given path, monitor the weld pool and the slag in it.

To do this, take thick metal and draw a line on it with chalk: you will need to lay a roller along it. You light the arc and begin to master the movements, learning to control the bath at the same time.

You won’t succeed the first time, or even the tenth time. You will probably use a dozen electrodes.

When the manual arc welding technique has been mastered: the bead is uniform, its width and height are constant (or almost), you can try to connect the parts.

You should get similar rollers. This way you can learn how to weld using electrodes correctly.

Read how to make a gazebo on a metal frame in this article, and here the construction of a shed on a metal frame is described.

How to weld metal correctly

Learning to hold the electrode correctly and move the bath is not enough for a good result. It is necessary to know some of the subtleties of the behavior of the metals being joined. The peculiarity is that the seam “pulls” the parts, which can cause them to warp. As a result, the shape of the product may differ greatly from what was intended.

Electric welding technology: before starting to apply a seam, the parts are connected using tack welds - short seams located at a distance of 80-250 mm from each other

Therefore, before work, parts are secured with clamps, ties and other devices. In addition, tacks are made - short transverse seams laid every few tens of centimeters. They hold the parts together, giving the product its shape. When welding joints, they are applied on both sides: this way the resulting stresses are compensated. Only after these preparatory measures do welding begin.

Read about the types of welds and joints (horizontal, vertical, ceiling) and how to weld them correctly here.

How to choose a current for welding

It is impossible to learn how to weld using electric welding if you do not know what current to set. It depends on the thickness of the parts being welded and the electrodes used. Their dependence is presented in the table.

But with manual arc welding, everything is interconnected. For example, the voltage in the network has dropped. The inverter simply cannot produce the required current.

But even under these conditions you can work: you can move the electrode more slowly, achieving good heating. If this does not help, change the type of movement of the electrode - passing over one place several times.

Another way is to use a thinner electrode. By combining all these methods you can achieve a good weld even in such conditions.

Now you know how to weld properly. All that remains is to practice the skills. Choose a welding machine, buy electrodes and a welding helmet and start practicing.

To reinforce the information, watch the video lesson on welding.

Source: https://sekretzh.ru/kak-pravilno-svarivat-metall-elektrosvarkoj.html