How to learn how to cook properly with electric welding?

Among the genius inventions of mankind, electric welding, undoubtedly, occupies one of the leading positions - so much universal and versatile is the method of joining parts by melting the electrode under the influence electric current.

The use of this method of joining metal parts and structures has long gone beyond the usual understanding of welding as a method of joining metal parts from ferrous metal.

For a long time, such types of electric welding as welding of aluminum structures, cast iron, joining parts under water, in an airless space, and even medical experiments on tissue joining organism.

And yet, the technology of electric welding has found the greatest development in construction and mechanical engineering, while the technology of arc welding in a protective environment (MMA) has become the most widespread.

Basic basics of welding

Mastering the first steps in welding, it is necessary to understand that successful training is the result of mastering both theoretical knowledge and practical skills.

Theoretical knowledge should include:

• knowledge of the theoretical foundations of the physical processes of electric arc welding;
• knowledge of the main characteristics and the principle of operation of different types of welding equipment;
• knowledge of the procedure for organizing work, instilled safety measures;
• knowledge of basic electrode markings, welding technology for various materials and components.

Step-by-step welding technology can be represented something like this:

• an electric current of high strength from 10 to 160 and even 250 amperes forms an electric arc between the electrode and the welded metal surfaces;
• due to the creation of an electric arc, the electrode temperature rises and the mixture burns, in combustion substances are involved that burn oxygen around them, forming a small volume of space protected from oxygen;
• the resulting high temperature gas melts the core of the electrode, which forms a weld pool in which the metal is in a liquid state and fills the seam between the parts to be welded.

Required materials / tools / protection

Moving on to the practical development of welding skills, you should choose a welding machine:

• Transformer welding machine - the type of welding equipment that produces alternating current was previously the most common type welding equipment, is simple, unpretentious in operation, but requires good wiring and normal network voltage;
• Welding inverter - a relatively new type of welding equipment, lightweight both in terms of work and in terms of weight, can work with rather significant differences voltage, in contrast to a transformer, produces a direct current; today it is the most promising type of equipment for amateur use;
• Welding semiautomatic devices - this is equipment for various types of welding carried out with a welding wire in an inert gas atmosphere, for working with semi-automatic welding the use of an inert gas cylinder is required, this is a very expensive equipment, however, a semiautomatic welding machine can weld even very thin details.

The minimum required set of welder's tools includes:

• welding hammer;
• metal brush;
• various clips and clamps;
• grinder with a set of cutting and grinding wheels.

Important! Considering that when the electrode burns, light is emitted 55-70 times more intense than the sun, a welder's mask with a special darkened glass is an indispensable element of the welder's protection.

In addition, the welder needs to have:

• Special heat-resistant gloves.
• Special welder's suit made of tarpaulin.
• It is also recommended to have special footwear - high-top boots or boots, while the trousers of the suit should be released over the boots or the tops of the boots. This may be an unfashionable solution, it will not allow scale to get inside the shoe during work.
• And if the welder wants to have fashionable hair on his head for a long time, then a hat or cap should become an obligatory element of clothing.

How to choose the right equipment, electrodes and gear

When choosing a welding machine for mastering the initial skills of work, it is enough to use a welding transformer, welding inverter as equipment of a higher class, it is reasonable to purchase with an eye to permanent work.

Standard cables to the welding machine, most often 1.5 meters long, which is clearly not enough for work at height or in small rooms, so it is recommended to purchase longer cables.

Welding machines of the latest generation, regardless of whether transformer or inverter are equipped today forced air system, so when buying it is useful to check their performance when the equipment is turned on to the network.

When purchasing electrodes for initial training, it is recommended for more effective mastery of skills buy not a pack of 5 kg, but buy several packs of electrodes of different diameters from 2 mm to 5 mm, 1 each kg. This number of electrodes is enough to understand how to cook.

An important point when buying electrodes is the marking - SSSI, the brand of electrodes for direct current, and it will be pointless to try to put the correct seam on the transformer apparatus. ANO-4 electrodes have universal qualities and can be used for welding with any device.

When choosing a protective mask, you should be aware that modern masks with automatic protection have the greatest effect, they do not require constant holding in the hand, the filter automatically turns on when an arc appears, but unfortunately, today such masks are still very expensive for many beginners masters.

Old-style masks with an invariable light filter, and especially those that are sold as standard in the welding kit, require some modification:

• At first, they do not have a protective glass, such an ordinary glass is inserted from the outside of the mask and protects the light filter from sparks and scale. Over time, such glass is simply removed and replaced with a new one.
• Secondly, the light filter itself in such masks comes with a fairly high degree of protection, for a beginner this is not entirely correct, because a beginner only masters the skills of work, and does not weld for 6 hours in a row. Therefore, it is recommended to replace the filter with a more transparent one, for example, a light filter No. 3, which gives a much better result.

Step-by-step instructions for welding

Preparation for welding involves not only the preparation of materials and equipment, but also strict adherence to safety rules!

You should be aware that welding work is work with an increased risk, therefore strict adherence to the rules operation of electrical installations, fire safety during work must be strictly observed:

• the workplace should provide free access to the welded structures;
• flammable materials must be removed;
• welding should be carried out in a dry room, while ensuring the rules of electrical safety;
• the welder must be equipped with an appropriate special suit, gloves, shoes.

Getting started:

• parts to be welded are cleaned from rust, paint, grease and other substances;
• welding places are carefully adjusted the burrs are cleaned with a file or grinder;
• the parts to be welded are pressed against each other and are recorded;
• the ground wire is attached to one of the parts by the holder;
• the welding machine is connected to the network;
• the electrode is inserted into the electrode holder with the side free from coating;
• with several movements, the electrode is held along one of the parts, to check the presence of current and ignition of the electrode;
• the mask is taken, the electrode is brought to the welding site, the mask is brought to the eyes and the parts are welded with several small seams of 3-5 mm;
• after welding the seams, the correctness of the connection is checked, since during arc welding, parts and the metal itself may be displaced, as a result of which sufficiently large gaps are formed;
• 1-2 minutes after the attachment of the parts with a welding hammer, carefully, putting on ordinary protective goggles, slag and scale are knocked off with light blows, the quality of the seam is checked;
• with a satisfactory result, welding is carried out continuous seam along the entire length of the parts;
• after 3-5 minutes the seam is cleaned with a hammer and a metal brush, the quality is checked;
• the device turns off, the workplace is being cleaned.

How to make different types of stitches

The skill of the welder is formed gradually, and you should not set the impossible task of learning how to cook with after 1-2 electrodes. Mastery will appear when the welder learns not only to hold the electrode correctly, but also to determine the size of the seam and bath by touch.

Igniting the arc, it is necessary to hold the electrode along the surface several times towards the seam, the flux will begin to gradually melt, and a bath will begin to form. Leading the electrode to the side along the seam, attention should be paid not to sparks, but to the formed pool, thus controlling the welding process.

When welding thick parts, you should first warm up the metal for 2-3 seconds, form a bath and only then form a seam.

Having learned to hold the arc, the next step in mastering the skill will be the ability to form a seam. Depending on the working conditions, the main skills will be considered welding skills:

• horizontal seam;
• vertical seam;
• pipe joint seam;
• ceiling seam (the welder is under the parts to be welded, all work is done at the top).

At the initial stage, it is enough to master the skills of creating a simple horizontal seam. For this:

• the electrode is kept at a distance of 2-3 mm from the surface, a bath is formed;
• with a slight movement of the electrode towards the side, the bath stretches along the seam;
• when moving, the tip of the electrode describes a semicircle, melting the metal in the form of scales.

After the end of welding, having cleaned the seam from slag, the result should be an even seam in the form of a strip of flakes covering one another.

When welding vertical seams, the seam is led from bottom to top or from top to bottom, so that the electrode reliably holds the bath, for this in addition to describing a semicircle with an electrode, it must be either brought closer or removed from the surface, boiling the metal to a sufficient depth.

The ceiling seam is formed in zigzag movements, but for such types of work, special electrodes are used, the coating of which forms a cup with molten metal inside. Such electrodes allow welding parts without spreading metal and creating a large number of sparks.

Features of pipe welding

Welding of pipes, depending on the location of the seam, is carried out as follows:

• a chamfer is formed at the ends of the pipes being welded;
• the ends to be welded are aligned with each other;
• a seam is seized at several points;
• with a horizontal arrangement from the lowest point, the sector is boiled to the middle of the pipe from the bottom, then from the top.

Professionals make the seam continuous, changing the position of the electrode; for a beginner, it is enough to scald the lower and then the upper part.

When welding pipes of large diameter and wall thickness, more than 6 mm pipes are welded in 2 layers, the more the diameter and thickness of the walls, the more layers you need to boil, conditionally every 6 mm of thickness add one layer.

Conventionally thin metal is considered to be metal up to 2 mm thick. The main problem when welding such products is the piercing of the through hole with the electrode. For this, electrodes of small diameter - 2 and 2.5 mm and a small current strength are used.

So, for welding metal of 1 mm, an electrode of 2 mm is enough and the current strength of the welding inverter is 30-35 amperes. In addition, for welding thin sheet metal and a thicker base, various overlays of thicker sheet metal are used, which can be welded on to a thin sheet.

Tips & Tricks

When welding parts, it must be borne in mind that there is a danger of thermal deformation of the metal, especially when the parts to be welded themselves are not quite fit tightly to each other in this case, it is recommended to first grab the structure in several places, and then make the final welding.

When planning welding work, it is necessary to dry the electrodes at a high temperature, the wet coating does not allow the formation of a normal seam, it crumbles, disintegrates, and forms a large amount of slag.

After the seam has cooled down, it is imperative to check for shells. They must be cleaned of slag and boiled again.