Welding is technological process obtaining reliable connections by heating the edges of parts to the melting point. Manual arc is its most common type. This method is highly productive, universal, technologically simple and available at home.

The essence of RDS

The edges of the parts being connected melt due to the heat generated by the ionized flow of particles between the cathode and anode - an electric arc. Ionization occurs due to the presence of current and short circuit between two poles with constant or variable characteristics.

The tool used to create and burn an arc is an electrode - a rod of metallic or non-metallic origin. The work can be performed with one or several rods with the possibility of creating an additional arc between them (three-phase arc welding). The ionized flow of electrons is surrounded by vapors from the tool and its coating, the melting metal of the parts being connected, and the results of their interaction with air. Types of electrodes for welding are determined taking into account all the characteristics inherent in a particular material.

Classification of rods by material of manufacture

At their core, all welding tools for welding welding are divided into consumable and non-consumable.

• Melting: metal tools, made of cast iron, steel, aluminum, copper (depending on the type of metal being welded). The rod acts as a cathode or anode, and also functions as a filler material to fill the weld pool and form a seam.
• Non-consumable: carbon, graphite, tungsten rods; perform only a primary function; additionally, filler metal wire is used; tungsten ones are needed for argon arc welding.

Among the first group there are electrodes:

• Without cover. This type of instrument is not used for RDS.
• Covered. An appropriate coating is used to maintain arc stability, protect the metal from burnout, from the influence of gases, and increase the mechanical characteristics of the weld through natural alloying (the penetration of alloying elements from the melting rod into the weld pool).

Application by type of work

The types of electrodes listed above have individual applications depending on the method of work.

Uncoated carbon electrodes - the primary welding invention, which belongs to N. N. Benardos and dates back to 1882 - are still used in modern times. Features: direct current, straight polarity, additional supply of filler wire, stable arc, the rod burns slowly, no carburization occurs. The use of reverse polarity reduces the characteristics of the arc and the weld (it becomes carburized).

Metal electrodes are the next invention in the field of welding technology, which belongs to N. G. Slavyanov (1888). Together with them, the prototypes of modern welding machines. Welding with melting rods has found more wide application in industry and has received active development. Today it is used in manual arc, automatic and semi-automatic (submerged arc) welding.

Due to high temperature melting point 3422˚С is used as a non-consumable material in argon arc welding. Thus, different welding technologies are suitable specific types electrodes.

Distribution by purpose

Purpose is the characteristic according to which absolutely all known electrodes are distributed. The types and use of rods are indicated by one letter (GOST 9466-75):

• structural steels, including low-alloy steels with a strength of 60 kgf/mm 2 (600 MPa) are marked in the markings with the letter “U” - carbon;
• alloyed structural steels having a strength of 600 MPa - “L”;
• high-alloy structural steels - “B”;
• heat-resistant alloy steels - “T”;
• alloys with special properties, which are characterized by surfacing - “N”.

The purpose is indicated on the unfolded stamp.

Rod coatings

Coatings of various compositions and origins are used in individual cases for various materials. The following types of electrode coating are used:

• Sour "A". Contains ferromanganese and ferrosilicon. Used for direct or direct current. Characterized by high melting rates. Best used for bottom seams.
• Rutile "R". Contains rutile (titanium dioxide), carbonates, aluminosilicates, ferromanganese, liquid glass. any position and type with direct or direct current. As a result of successive chemical reactions A protective slag is formed, which prevents the elements from burning out. Good quality, low toxicity.
• Cellulose "C". The composition includes cellulose, manganese ore, talc, rutile, ferromanganese. Shielding gases are formed around the arc and weld pool. For all seams; high speed of work; good quality; overheating must not be allowed; large losses due to splashing. Used for permanent connections of pipelines.

• Basic B's. Contains calcium carbonates and fluorides. Protective carbon dioxide is formed due to the reaction of carbon from carbonates with arc combustion oxygen. It is advisable to perform work under direct current with reverse polarity. During alternating welding, a low-quality seam is obtained; additional technologies are required to improve its mechanical characteristics.
• Other "P". Contain alloying elements. The quality of the weld is improved by introducing into it a certain amount of alloying elements from the melting electrode.
• Special. Contains liquid glass with resin-containing substances. Protects against moisture penetration. Applicable for

All coated electrodes have specific purposes. The main type of coating is rutile due to its versatility. Coatings perform protective functions by deoxidizing the alloy in the weld pool, adding alloying elements to it, and forming a halo of protective gases or slag. This allows you to avoid lower quality seams than the materials of the edges of the parts and ensure the formation of high-quality welded joints.

Requirements for tools established by GOST 9466-75

• Electrodes must be made of high quality material.
• The coating must be solid and free from significant defects (small dents and cracks without swelling or porosity are allowed).
• High mechanical resistance to random shock loads.
• Different types of electrode coatings must melt evenly, not crumble, not form uneven islands, and not splash beyond the permissible characteristics.
• The rod must ensure the formation of a high-quality weld: without cracks, pores, or local excess of deposited metal.
• A rational choice, taking into account all the necessary parameters and adherence to technology, is the key to the formation of a reliable, durable connection.

Choosing a rod depending on the size

A novice welder is more familiar with the types of electrodes determined by size. The diameter of the tool with which the work will be carried out is selected strictly in accordance with the thickness of the part to be welded. It is not encrypted, but is clearly indicated on the instrument labeling. The length of the electrode is also fixed according to its diameter. It is important to have an idea of ​​the length of the stripped bare end of the tool.

Thickness of prepared edges, mm	Electrode diameter, d, mm	Electrode length, mm	Length of stripped uncoated end, mm
			20
			25
			25
			30
			30

For home welding work the most commonly used types of electrodes for arc welding with a diameter of 2-4 mm. Thick rods are suitable for repair shops and production.

Coating thickness

It has its own designation in the instrument marking. It is determined by the coefficient of its ratio D (mm) to the thickness of the rod itself d (mm). Distributed into 4 groups:

• thin “M” (coefficient up to 1.2);
• average “C” (the coefficient has values ​​ranging from 1.2 to 1.45);
• thick “D” (coefficient - within 1.45-1.8);
• especially thick “G” (coefficient value over 1.8).

The results of the work are influenced not only by the types of coatings of manual arc welding electrodes, but also by the thickness of the coating layer itself, as well as the dimensions of the rod. Correct selection electrode size provides good speed work, quality parameters of the arc and the formed connection.

Selection of rods depending on the type of seam and its spatial position

Seams have several classifications:

• Depending on the action of the main forces: flank, frontal, oblique, end.
• In accordance with the position of the parts being welded: butt, corner, T-joints, overlay joints.
• Depending on the presence of bevel of the edges: with bevel, without bevel.
• In accordance with the position in space: lower, upper, horizontal, vertical.

The choice is influenced by the spatial position of the seam. Its type is indicated by the rod marking.

• 1 - for welding in all positions;
• 2 - exceptions apply only to vertical seams from top to bottom;
• 3 - for bottom seams, horizontal vertical plane, vertical from bottom to top;
• 4 - for the bottom seams.

The type of weld relative to the spatial position is taken into account when determining the current values.

The influence of arc electrical parameters on the choice of welding tools

Welding can be carried out under direct or direct current, direct (“minus” on the electrode, “plus” on the product) or reverse polarity. The choice depends on the material being welded and its properties. The type of current is determined by the power source.

The main equipment that generates and (or) converts current can be used: transformers and oscillators (reduce the network voltage to the required values), converters and rectifiers (convert the alternating current of the network into direct current of the welding process).

The parameters required to ignite the arc differ significantly from those observed during its maintenance. Voltage required for fast education arc is called voltage idle move. Let us consider the voltage values ​​required to ignite the arc and to maintain its combustion.

Types of welding electrodes vary depending on the network characteristics and are designated by numbers from 0 to 9:

• 0 - only for direct current of reverse polarity;
• 1-9 - for any currents;
• 1, 4, 7 - any polarity;
• 2, 5, 8 - straight;
• 3, 6, 9 - reverse;
• 1-3 - open circuit voltage 50 V;
• 4-6 - 70 V;
• 7-9 - 90 V.

The choice affects the features of the technology and quality characteristics seams. Thus, the smallest depth of boiling is ensured by working with variable network parameters. Used for unpretentious materials and simple designs. When welding with an arc with constant characteristics and reverse polarity, the depth of the weld pool and the mechanical properties of the seam are 50% higher than even with direct polarity. Used for stubborn materials and critical structures.

Determination of current strength

When arc welding manual type it can be different - from 30 to 600 A. The choice of the required value is carried out depending on the diameter of the working electrode and the type of seam relative to the spatial position. Calculated as follows:

• For bottom seams: I=d*k.
• For the top ones - I=k*d*0.8.
• For horizontal ones - I=k*d*0.85.
• For vertical seams - I=k*d*0.9.

where I is the current strength, A;

d - diameter, mm;

k - coefficient, A/mm.

The coefficient depends on the diameter of the rod:

• for electrodes with a thickness of 1-2 mm - k=25-30 A/mm;
• 3-4 mm - k=30-45 A/mm;
• 5-6 mm - k=45-60 A/mm.

Increasing the force speeds up the welding process. Excessing the permissible values ​​can lead to overheating of the edges, excessive burnout of components, and deterioration in the quality of the weld.

Marking

In order to consider all the nuances of labeling, it is important to bring standard example in accordance with GOST 9466-75 and 9467-75: (E42A-UONI-13/45-3.0-UD)/(E432(5)-B10).

• Brand: UONI-13/45.
• Type: E42A - electrode for RDS, provides a weld strength of 420 MPa with increased ductility (A).
• 3.0 - diameter 3 mm.
• U - for welding carbon steels and low-alloy structures.
• D - thick coating.
• E432 (5) - indices in which the characteristics of the connection and deposited metal are encrypted.
• 43 - tensile strength not less than 430 MPa;
• 2 - relative elongation not less than 24%;
• 5 - welding is possible at temperatures down to -40˚С; this ensures the minimum permissible metal value of 34 J/cm 2 .
• B - main coating.
• 1 - spatial position of the seam: any.
• 0 - welding only with an arc with constant characteristics and straight polarity.

Using different types and brands of welding tools

Everything discussed above relates more to the marking of electrodes for RDS steel. It is important to provide examples of rods used for a variety of ferrous and non-ferrous metals. Below are the most common types.

The types of electrodes are distributed depending on the metal being welded and the specified typical mechanical characteristics of the seam.

Carbon low-alloy steels are welded with rods of the following types:

• E42: grades ANO-6, ANO-17, VSC-4M.
• E42: UONI-13/45, UONI-13/45A.
• E46: ANO-4, ANO-34, OZS-6.
• E46A: UONI-13/55K, ANO-8.
• E50: VSC-4A, 550-U.
• E50A: ANO-27, ANO-TM, ITS-4S.
• E55: UONI-13/55U.
• E60: ANO-TM60, UONI-13/65.

High strength alloy steels:

• E70: ANP-1, ANP-2.
• E85: UONI-13/85, UONI-13/85U.
• E100: AN-KhN7, OZSh-1.

High-strength alloy steels: E125: NII-3M, E150: NIAT-3.

Metal surfacing: OZN-400M/15G4S, EN-60M/E-70Kh3SMT, OZN-6/90Kh4G2S3R, UONI-13/N1-BK/E-09Kh31N8AM2, TsN-6L/E-08Kh17N8S6G, OZSh-8/11Kh31N11GSM3YuF.

Cast iron: OZCh-2/Cu, OZCh-3/Ni, OZCh-4/Ni.

Aluminum and alloys based on it: OZA-1/Al, OZANA-1/Al.

Copper and alloys based on it: ANTs/OZM-2/Cu, OZB-2M/CuSn.

Nickel and its alloys: OZL-32.

From the above list we can conclude that the marking system is very complex, and is based on approximately the same principles for encoding the characteristics of the rod, its coating, diameter, and the presence of alloying elements.

The quality of the welding joint depends on rational technological scheme. The following factors influence which types of electrodes to choose:

• The material to be welded and its properties, presence and degree of alloying.
• Product thickness.
• Seam type and position.
• Specified mechanical properties of a joint or weld metal.

It is important for a novice welder to understand the basic principles of selecting and marking tools for welding, as well as to operate with the distribution of rod grades according to their intended purpose, to know the main types of electrodes and to use them rationally during welding work.

Connecting several parts in monolithic structure often occurs using welding equipment. To obtain the required quality of connection, it is necessary not only to rationally select the welding method, but also the corresponding welding electrodes.

Welding work

Basic requirements for electrodes

The variety of weldable substances and welding methods requires a wide range of electrodes used.

But they all have to answer general requirements:

• ensure stability of the arc, a small radius of spattering of the rod, coating, high productivity of welding work;
• create conditions for the formation of a high-quality welding seam;
• make the welding process uniform;
• maintain physical, chemical, technological properties during a specific welding.

A special place in the requirements is toxicity. Electrodes must emit a minimum amount of toxic substances during operation.

Classification of welding fittings

Electrodes are used as the main element for manual arc welding. There are two types of electrodes:

• melting, which correspond to the composition of the substances being welded;
• non-melting three types: carbon, graphite, tungsten.

Several methods are used to classify electrodes. According to their purpose, electrodes are distinguished for connecting stainless steel, non-ferrous metals, various types of steel, and cast iron.

Note! Electrodes for manual arc welding are marked in the following way: B - high-alloy steel, L - alloy steel in structures with temporary tensile strength, T - heat-resistant steel, U - carbon and low-alloy steel, N - surface layers with special properties.

The type of construction involves obtaining different types of seams. This can be a vertical, ceiling or bottom seam. For each type of seam, a special electrode is selected:

• for any position;
• not used for welding vertically from top to bottom;
• for the lower, vertical from bottom to top and for horizontal, located in the vertical plane;
• for the bottom.

The variety of coating material and its thickness are also classified by electrodes. The electrodes are covered on top protective layer from a composite composition, it includes the following substances:

• stabilizers for the arc combustion process;
• granite, silica, titanium and manganese ores, components for the formation of slag from which the film is created. This slag film prevents oxidation processes;
• marble, magnesite, starch, wood flour, forming a gas film to protect the weld pool. Can be inorganic and organic;
• silicon, magnesium, titanium as deoxidizers and alloying elements;
• ferromanganese, ferrosilicon, ferrotitanium for the recovery of metals from oxides;
• bentonite, kaolin, dextrin to improve plastic properties.

Note! To classify types of coating, the following designations are used: A - acidic, B - basic, - C cellulose, R - rutile, P - other. Sometimes a combination of letters is used if the coating is of a mixed type.

The electrodes are covered with a thin protective layer, medium, thick and even especially thick. Marking of the thickness of the coating, which is defined as the ratio of two diameters - with the coating and the rod itself:

• M - ratio up to 1.2;
• C - ratio up to 1.45;
• D - ratio up to 1.8;
• G - ratio more than 1.8.

Important technical indicator is the applied type electric current. There are electrodes connected to sources of constant or alternating current, as well as with various types polarity.

Basic labeling standards

All designations can comply with two systems for marking electrodes for welding: according to GOST and the international ISO standard. The European standards EN and the American standard AWS are also used.

Electrode marking

Domestic manufacturers are guided by GOST 9466-75, 9467-75, 10051-75, 10052-75 and the brands of electrodes for welding are applied in two groups of signs. The markings include both numbers and letters. The first group is only internal, and the second is adapted to international standard.

The first group of marking symbols consists of five positions:

1. electrode type. This designation will help you figure out what type of steel it can weld. Manual welding is designated by the letter E. Further numbers indicate compliance with the tensile strength of steel. This group may end with the letter A if it is intended to form a plastic seam. May also include a hyphen indicating that the number after it indicates the carbon content as a percentage;
2. brand of electrode according to the composition of the coating;
3. wire diameter, indicated by numbers with the dimension mm;
4. the type of steel for which this electrode is used;
5. coating thickness.

The second group of marking symbols has six positions and is more consistent with international requirements:

• a figure showing the value of the tensile strength of steel with a dimension of 10-7 Pa;
• a number indicating the relative elongation;
• index number defining the minimum temperature at which impact strength meets the standard;
• type of coating, indicated by one or two letters. Two letters are placed in cases where a mixed coating is used;
• a number that will help determine whether a given electrode is suitable for performing the required welding position;
• parameter welding current in index form. Each index from 0 to 9 corresponds to a pair of parameters: polarity and permissible open-circuit voltage in V.

The choice of electrode depends on many components. This includes the type of metal and its thickness, and the method of welding. To be able to carry out various welding operations, several electrodes are selected at once or with more universal indicators, which can be found out from the applied markings.

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Marking of electrodes for manual arc welding

Home » Welding work at the dacha.

The production of critical metal structures is carried out using electric arc welding. There are many ways to obtain permanent connections - MIG/MAG ( mechanized method in protective gases), TIG (argon arc method). But in everyday life it is most often used manual welding piece electrode (MMA).

How to decipher electrode markings?

Regulatory documentation a certain marking of coated electrodes is regulated, which indicates their main characteristics. To choose the right welding material, you need to know and be able to decipher all the notations.

For example:

E46 – ANO-21– 3.0 – UD E – 430(3) – R11

Symbols:

• E46 – electrode type;
• ANO-21 – name;
• 3.0 – section;
• U – designed for welding structural carbon steels with tensile strength up to 600 MPa;
• D – powder coating thickness (thick);
• E – electrode;
• 430(3) – indicates technical specifications deposited metal (determined in accordance with GOST 9467, as well as 10051 and 10052);
• P – type of powder coating (rutile);
• 1 – recommended positions of the electrode rod during the welding process (all);
• 1 – requirements for the arc power source.

Description and types of letter and number positions in markings

The types of electrodes are E38, 42, 42A, 46, 50, 50A, 55, 60, 70, 85, 100, 125 and 150. According to this brand, the mechanical properties of the welded joint are determined.

Marking of electrode purpose:

• U – structural steels;
• L – alloy steel grades with a strength of more than 600 MPa;
• T – heat-resistant metal;
• B – for metals with a high percentage of alloying elements;
• N – for surfacing works.

Thickness and type protective coating:

Possible spatial position of the piece electrode during the welding process:

1. Can be cooked in any position.
2. An exception is vertical welding, when the electrode moves from top to bottom of the part.
3. Welding is possible in the lower position, horizontal (with the position of the welded part in a vertical plane) and vertical, when the electrode is from top to bottom.
4. Welding can only be done in the lower position.

• What is soldering flux used for?
• Electrodes for cast iron: marking

samanka.ru

We study the marking of electrodes for welding

All welding electrodes are marked and intended for use. It contains all the information about the electrode itself, for example about its composition, and sometimes even about the manufacturer. Understanding all these designations, you can always independently select the required materials for the connection.

First of all, it is always worth checking whether the selected electrode is suitable state standards. To do this, the packaging must have the inscription “GOST” and several numbers after it.

If all this is present, you can safely continue choosing welding electrodes, selecting them according to other indicators, without fear of fakes and low-quality goods.

Composition and purpose of the electrode

The electrode is made in the form of a rod; it can be either metal or made of other materials, depending on its purpose. But in general its purpose is to supply current to the welding site. Therefore, an experienced welder will always pay attention to the electrical conductivity of the material. For the production of electrodes, it is customary to use wire that contains alloys with varying degrees of alloying. It is worth paying attention to the external coating. It is applied to provide protection against external irritants such as nitrogen or oxygen. Other advantages of the coating include maintaining the stability of the welding arc and removing possible impurities - they may be in the molten metal.

Let's consider several components that ensure the quality of the electrode coating:

1. Manganese ore.
2. Titanium concentrate.
3. Quartz sand.
4. Kaolin.
5. Marble.

Components that create a gas-forming environment include dextrin and flour. The goal of any welding is to ensure a high-quality weld, with corrosion resistance and high strength. To do this, the electrode must contain the following alloying impurities:

• vanadium;
• manganese;
• nickel;
• chromium;
• titanium.

There can be many more of them, these are just the main ones and the most common ones.

Marking

All electrodes are globally divided into two types: melting and non-melting. The first include copper, bronze, steel and copper materials. Sometimes uncoated products are found; they are usually used as wire for connections using protective gas. And non-consumable ones are lanthanum tungsten or thoriated electrodes.

By type of coverage

If a product is marked with the letter "A" - this indicates that its coating is acidic, it should be used for steel structures, if the metal being joined is observed high level carbon and sulfur.

The letter “B” will indicate that working with such products in a vertical position is prohibited - by the way, as is the case with the letters “A” and “P”. The letter “C” means that there is no prohibition on any non-standard positions and these electrodes can produce high-quality work in any position. But one drawback was noticed - in the form of excessive spattering and constant monitoring of the temperature of the product.

Fine marking details

Naturally, this is not all the designations. There are a lot of nuances. The first numbers and letters usually indicate the limit maximum load. If the following marking is present: “E41”, this means that the parts that were welded can withstand a load of 41 kilograms per 1 square mm. There are also other options that allow you to characterize the welding product:

1. “U” - shows that you can safely work with low-alloy and carbon steels;
2. “T” and “B” - you can connect high-alloy and heat-resistant steel;
3. “L” - work with alloyed structural alloys;
4. “N” - useful in the case of surfacing a layer with any properties.

Coating layer thickness designation:

• "M" - thin;
• "D" - thick;
• "C" - average;
• "G" - maximum.

The numbers at the end of the marking are written to understand the spatial position of the products and the current value that is recommended to be used in this case.

More details:

• “1” - parts can be welded in any position;
• “2” - except for the top-down position;
• “3” - restrictions on ceiling orientation are added to the second option;
• “4” - only for the bottom seams.

Additionally, the box containing the products may be marked with marks indicating that the product inside is fragile and should not be exposed to moisture. All these markings are easy to decipher even on an intuitive level, having general knowledge of welding. This will greatly facilitate the search for the required material for welding.

Sergey Odintsov

electrod.biz

Electrode marking

Home page» Electrode marking

For welding carbon and low-alloy steels, as well as alloyed steels with increased and high strength, the electrode type designation consists of:

• - index E - electrode for manual arc welding and surfacing:
• - numbers following the index, indicating the value of tensile strength σв;
• - index A, indicating that the weld metal has increased properties of ductility and impact strength.

For welding heat-resistant, high-alloy steels and for surfacing, the electrode type designation consists of:

• - index E - electrode for manual arc welding and surfacing;
• -hyphen (dash);
• - the number following the index indicating the average carbon content in hundredths of a percent:
• - letters and numbers indicating the percentage of chemical elements.

The order of arrangement of letter designations of chemical elements is determined by a decrease in the average content of the corresponding elements in the deposited metal. With an average content of the main chemical element less than 1.5% figure after letter designation chemical element is not specified. If the average content of silicon in the deposited metal is up to 0.8% and manganese up to 1.0%, the letters C and G are not affixed.

For welding carbon and low-alloy steels with σв up to 490 MPa (50 kgf/mm2), 7 types of electrodes are used: E 38; E 42; E 46; E 50; E 42A; E 46A; E 50A.

For welding carbon and low-alloy steels with σw from 490 MPa (50 kgf/mm2) to 588 MPa (60 kgf/mm2), 2 types of electrodes are used: E 55; E 60.

For welding alloy steels of increased and high strength with σ in excess of 588 MPa (60 kgf/mm2), 5 types of electrodes are used: E 70; E 85; E 100; E 125; E150.

For welding heat-resistant steels - 9 types: E-09M; E-09MH; 3-09X1 M; E-05X2M; E-09X2M1; E-09Х1МФ; E-10Х1МНБФ; E-YUHZSHBF; E-10Х5МФ.

For welding high-alloy steels with special properties - 49 types: E-12X13; E-06X13N; E-10X17T; E-12X11NMF; E-12X11NVMF and others.

For surfacing surfaces of layers with special properties - 44 types: E-1 OG2; E-1 OGZ; E-12G4; E-15G5; E-16G2ХМ; E-ZOG2ХМ and others.

For welding carbon and low-alloy steels with σв up to 588 MPa (60 kgf/mm2) - marked with the letter U: For welding alloy structural steels with σв over 588 MPa (60 kgf/mm2) - marked with the letter L: For welding heat-resistant steels - marked with the letter T: For welding high-alloy steels with special properties - marked with the letter B; For surfacing surfaces of layers with special properties - the letter H;

Depending on the ratio of the diameter of the electrode coating D to the diameter of the electrode rod d, electrodes are divided into the following groups:

• with a thin coating (D/d ≤ 1.2) - marked with the letter M;
• with medium coverage (1.2
• with thick coating (1.45
• with particularly thick coating (D/d > 1.8) - G.

6.1 For electrodes used for welding carbon and low-alloy steels with σв up to 588 MPa (60 kgf/mm2)

Different types of electrodes have their own markings. The marking indicates the basic information and parameters of a particular type of electrode. And, in order to learn to understand what properties a particular electrode has, we will talk about how to decipher the electrode markings.

Before starting any welding work, ensure that the electrode meets the national standard. To do this, on the packaging of the electrodes, find the abbreviation “GOST – ХХХ-ХХ-Х”), where instead of “X” a combination of numbers will be displayed. Let's look at the electrode markings using one of them as an example. So, in our example, consider the electrode E46-LEZMR-3S (also called the “blue” electrode).

The marking may differ from what will be described in the example, however, the decoding principle remains the same. Reason various markings is the use of electrodes in certain welding conditions, when working with various metals, materials, and so on.

So, the electrode is E46-LEZMR-3S. Any electrode is marked with 12 combinations (ciphers), thanks to which you can find out this or that information about it.

"E46"– this combination indicates the type of electrode, which in this case is intended for welding carbon and low-alloy steels, the tensile strength of which reaches up to 46 kgf/sq.m. mm.

"LEZMR"– indicates the brand of the electrode and the manufacturer (in this case, it is the Losinoostrovk Electrode Plant, and the brand of the electrode is MP-3S).

«Ø» – a symbol indicating the diameter of the electrode (the diameter itself is indicated elsewhere on the packaging).

"UD"– a combination indicating the purpose of the electrode.

- "U" – indicates the possibility of welding carbon and low-alloy steels, the tensile strength of which reaches a value of 588 MPa, or 60 kgf/sq.mm.

- "D" – indicates the coefficient of coating thickness, in this case, it is a thick coating of 1.45

"E"– index indicating the melting coating of the electrode.

"43"– a value indicating tensile strength (value 43 corresponds to a value of 430 MPa, or 44 kgf/sq.mm.).

"1"– indicates relative elongation, the value “1” corresponds to 20%.

"(3)"– this designation indicates the minimum temperature at which the impact strength of the weld metal should be at least 32 J/sq.cm, the value “3” corresponds to a temperature of -20°C.

"RC"– a value indicating the type of coating, in this case, the combination “RC” indicates a rutile-cellulose coating.

"13"– a combination indicating permissible spatial positions, welding current and open circuit voltage. In this case, “1” corresponds to the value “for any spatial position,” and the number “3” indicates the possibility of welding with alternating and direct current of reverse polarity, as well as an open circuit voltage of about 50V.

Electrodes are marked approximately in this way. To decipher the designations of the electrodes, we suggest that you familiarize yourself with detailed information and all possible designations that are found in the electrodes.

Electrode type. So, for manual arc welding or surfacing, the electrode marking will always begin with the value “E”. For welding carbon and low-alloy steels, the electrode type marking will consist of three values. From the letter “E,” a number that indicates tensile strength, and the letter “A,” which indicates that the weld metal has increased ductility and toughness.

For welding heat-resistant or high-alloy steels, as well as for surfacing, the electrode type may have additional symbols indicating the percentage of other chemical elements.

Electrode brand. In this case, each type of electrode can correspond to one or several brands.

Electrode diameter. The electrode diameter value will correspond to the diameter of the metal rod of this electrode.

Purpose of the electrode. In this case, it is enough to be guided by the table below.

Coating thickness coefficient. This value indicates the relationship between the diameter of the electrode coating and the diameter of the metal rod. Depending on this, the value of the coefficient will correspond to the following values:

A group of indices indicating the characteristics of the weld metal or weld metal. For electrodes that are used in welding carbon and low-alloy steels (tensile strength of which is up to 588 MPa).

The widespread use of technology for connecting various parts using electric current and a consumable electrode required the search for new technologies to enable high-quality work with literally every type of material, with every grade of metal.

To achieve wide distribution and at the same time ensure high-quality connection of highly specialized structures and elements, it is possible to connect universal welding machines in welding technology and individual selection of consumable electrodes. The economic feasibility of this approach is entirely justified - for welding machines, the set of functions and technologies allows you to work with ferrous metals, alloy steels and cast iron structures, but the individuality of the approach is achieved by selecting consumables - welding electrodes.

Specifics of selection of welding electrodes

The use of electric welding for joining metals, in addition to the generally accepted and understandable physical processes that affect the process of joining the parts being welded, has another, very important point - the properties of parts designed for use in various industries and industries. First of all, the properties of metals are taken into account - structural steels, alloy and low-alloy steels, cast iron or structures made of non-ferrous metals. And in this case, the weld must meet the maximum conditions and grade of the base metal. This correspondence of welding electrodes to the base material is achieved by using a highly specialized metal composition as the core, and using the most suitable components as coating.

Types and brands of electrodes

The use of welding electrodes, depending on the properties of the material being welded, depends, first of all, on the composition of the metal core. Here, during production, several factors are taken into account that affect the quality of the seam:

• the direct purpose of the electrode for welding a certain type of metals and alloys;
• working conditions, spatial position of the seam;
• thickness of connected parts and structures;
• specifics of the formation of a weld pool and a protective cloud of gases;
• highly specialized properties of the seam - tensile strength, bending, fluidity of the liquid seam, oxygen saturation.

Taking into account these and other conditions for labeling the final product and the conditions of production itself is required for all domestic manufacturers of electrode products by the relevant state standards and assortments. An electrode that is marked accordingly must comply with the specifications regardless of the manufacturer. At the same time, the markings applied to the packaging must correspond to the contents both in quality and quantity.

Brands of electrodes for arc welding

Today, the most widely produced electrodes are for joining parts made of ferrous metals and steels. That is why the most commonly used markings are focused on welding steel parts and grade products depending on the carbon content in the metal. This gradation also corresponds to the main steel grade:

• “U” is the main part of structural ferrous metal with a relatively low content of alloying additives and an average level of carbon presence. The quality of the weld must withstand a tensile force of about 600 MPa.
• “T” - specific electrodes for alloy steel grades, which have refractoriness and high heat resistance, weld breaking force is about 600 MPa;
• “N” – electrodes for additional surfacing of an additional layer of metal on the surface, and the metal may have special properties;
• “A” – conditionally ductile alloys and metals.

Selecting an electrode brand

The quality of the weld, its structural and plastic properties, and the ability to withstand various deformations depend largely on the quality, composition and thickness of the coating layer on the metal core.

To mark the coating layer and indicate its thickness, a letter designation is used that displays the ratio of the thickness of the coating to the diameter of the metal core. It should be noted that the basis here is the diameter/coverage ratio in percentage terms, and not a specific thickness number in millimeters.

For labeling, it is customary to take a ratio of 20, 45, 80 and more than 80%. Such indicators are marked respectively with the letters “M”, “S”, “D”, “G”. The most popular ratio is approximately 45%, marked “C”, indicating about 70% of all produced electrodes of all types. This marking allows you to select consumables for the work depending on the complexity and importance of the parts being welded.

Taking into account the amount of core coating that forms the protective cloud of the weld pool when selecting the type and grade is very important, as well as taking into account what materials the coating itself is made of - to indicate the type of the main component of the coating, letter designations are used that correspond to the most common types of coating materials :

• acid coating – marked “A”;
• for the main types the letter code “B” is used;
• the cellulose content of the coating will correspond to the letter “C”;
• the component is marked “P”;
• for other types, the marking is combined with a common code “P”.

Attention! Two-component types of coatings that have highly specialized areas of application are marked by combining the main letter codes, with the first letter indicating the predominant component in the coating composition.

Decoding the brand of electrodes

Achieving maximum performance in welded joints of structures is achieved by using types of consumables that have one more property during operation - spatial position when forming a weld pool. The ability to lay a strong seam in a horizontal position may be lost if this electrode is used for ceiling work, vertical welding, or applying an inclined seam. Simply put, if in one position the seam lies flat, then when welding with the same brand in another position the seam will be intermittent, dripping, flowing down the surface of the metal.

The parameters for using the electrode, depending on the spatial position, are marked with a digital code:

• 1 – universal type of use;
• 2 – type suitable for use in most positions, except vertical;
• 3 – suitable for both vertical and horizontal seams, except for work under the ceiling;
• 4 – horizontal weld electrode.

Types of electrodes

For particularly important structural elements that have increased requirements for the strength of connections, electrodes are used that are designed for a very narrow specialization, for example, for alloy steels or elements.

The advantage of these special grades is the complete compliance of the core composition with the composition of the structures being welded. There is no need for additional strengthening or weakening of the welding current, or special arc formation skills; the temperature regime of the coating combustion itself ensures maximum melting of the core and heating of the surface of the part itself. Such electrodes form a seam without significant deformations or changes.

For these purposes, the brands E-70, ANP2, NIAT 3M, UONI-13/85, N20/Sv-12H2NMAVI, OZS-11, TMLZU, TsL-45 are most often used.

Surfacing or welding of cast iron products containing a large amount of carbon requires the use of electrodes similar in composition to cast iron, which is why the OK series has such specific properties. This brand is characterized by low metal fluidity in the range of 300-500 MPa, a relatively low strength indicator compared to steel cores - 460-640-720 MPa, and of course a small mechanical elongation of the seam of 6-40% depending on the marking. At the same time, OK-92 grade electrodes with indexes from 05 to 86 have an enviable cold weld hardness - up to 240-260 HB.

Attention! Welding electrodes intended for welding and surfacing cast iron are not recommended for use on metal structures. The formed seam will not have the design characteristics due to the high carbon content in the electrode metal .

Welding of non-ferrous metals and alloys

The joining of light non-ferrous metals and their alloys in common use today is still in very limited use, but this does not mean that welding technologies do not have the ability to work with these materials.

To connect aluminum structures, despite the presence of a protective chemical layer of metal, electrodes of the OZA brand are used; their markings correspond to the following metals being welded:

• technical aluminum 99% purity of metal content – ​​OZA1;
• aluminum alloys, including those with silicon – OZA2, OZANA2;
• technical aluminum – OZANA1;

Copper structures, most often connected by soldering, can also be connected by welding; electrodes Komsomolets 100, ANC/OZM series 2,3,4 are applicable here.

And for welding different grades of nickel, the OZL-32 electrode is used.

Specification of electrodes for creating structural parts

The creation of separate, specific structures with large mass and dimensions, mounted directly on the assembly site, requires the use of electrodes for cutting metal. For example, in shipbuilding, when steel sheets are supplied in one piece and holes are made directly on the slipway, electrodes are used that are capable of creating a high melting temperature and the ability to operate at maximum welding current.

For such and similar work, OZR1 and OZR2 electrodes are used to cut metal up to 40 mm thick, make holes, cut off beads, and eliminate defective areas of welded joints.

Electrode brand: GOST

The alphanumeric designation of the name, usually located in tabular form on the packaging, is often duplicated on the coating of the electrode itself. This convenience allows you to easily identify the type and brand of electrode.

Typically the code consists of several groups of ciphers. Each group has its own meaning and application characteristics:

• the first alphanumeric designations identify the purpose, for example, E-46 - which means the main specificity is the connection of steel parts made of alloy and carbon steel grades;
• Next comes the brand of the electrode, it classifies the manufacturer;
• the next block of code is the purpose of the coating and its layer, for example, UD is a thick coating (D) for carbon grade steel (U);
• separate letter designation of the type of steel core E – melting electrode;
• the following numbers characterize the ultimate strength of the seam during a tensile test, here, 43 is a force of 430 MPa;
• the number followed by the number in brackets is a designation of relative elongation with a temperature characteristic of maintaining the viscosity of the metal;
• the remaining alphanumeric designations indicate the type of coating and conditions of use, for example RC13 - cellulose coating for universal work at normal current with the possibility of using reverse polarity.

Attention! Obtaining a high-quality welded joint in most cases depends on correctly selected electrodes by type and brand. At the same time, the selection of consumables requires compliance with other requirements - the correct choice of diameter, type of current used, and the quality parameter of the electrode in terms of coating moisture.

CLASSIFICATION OF ELECTRODES

MARKING EXAMPLES: DESIGNATION OF SPATIAL POSITIONS FOR VARIOUS ELECTRODES

MARKING OF WELDING ELECTRODES

MARKING EXAMPLES:

DESIGNATION OF SPATIAL POSITIONS FOR VARIOUS ELECTRODES

Electrode type

For welding carbon and low-alloy steels, as well as alloyed steels with increased and high strength, the marking consists of:

index E

numbers following the index indicating the value of tensile strength in kgf/mm 2;

index A, indicating that the weld metal has increased properties of ductility and impact toughness.

For welding heat-resistant, high-alloy steels and for surfacing, the symbol consists of:

index E- electrode for manual arc welding and surfacing;

• the number following the index indicating the average carbon content in hundredths of a percent;

  letters and numbers indicating the percentage of chemical elements. The order of arrangement of letter designations of chemical elements is determined by a decrease in the average content of the corresponding elements in the deposited metal. If the average content of the main chemical element is less than 1.5%, the number behind the letter designation of the chemical element is not indicated. If the average content of silicon in the deposited metal is up to 0.8% and manganese up to 1.0%, the letters C and G are not affixed.

Designation of metals

For welding carbon and low-alloy steels with tensile strength up to 490 MPa (50 kgf/mm 2), 7 types of electrodes are used: E38, E42, E46, E50, E42A, E46A, E50A. For welding carbon and low-alloy steels with tensile strength from 490 MPa (50 kgf/mm2) to 588 MPa (60 kgf/mm2), 2 types of electrodes are used: E55, E60. For welding alloy steels of increased and high strength with a tensile strength over 588 MPa (60 kgf/mm 2), 5 types of electrodes are used: E70, E85, E100, E125, E150.

For welding heat-resistant steels - 9 types: E-09M, E-09MH, E-09H1M, E-05H2M, E-09H2M1, E-09H1MF, E-10H1MNBF, E-10H3M1BF, E10H5MF. For welding high-alloy steels with special properties - 49 types: E-12Kh13, E-06Kh13N, E-10Kh17T, E-12Kh11NMF, E-12Kh11NVMF, etc. For surfacing surface layers with special properties - 44 types: E-10G2, E- 10G3, E-12G4, E-15G5, E-16G2KhM, E-30G2KhM, etc.

Electrode brand

Each type of electrode may correspond to one or more brands.

Electrode diameter

The diameter of the electrode (mm) corresponds to the diameter of the metal rod.

Purpose of the electrode

For welding carbon and low-alloy steels with tensile strength up to 588 MPa (60 kgf/mm 2) - marked with the letter U;

For welding alloy structural steels with tensile strength over 588 MPa (60 kgf/mm 2) - marked with the letter L;

For welding heat-resistant steels - marked with the letter T;

For welding high-alloy steels with special properties - indicated by the letter IN;

For surfacing surface layers with special properties - marked with the letter N.

Coating thickness coefficient

Depending on the diameter ratio of the electrode coating D to the diameter of the metal rod d, electrodes are divided into the following groups:

with a thin coating (D/d≤1.2) - marked with a letter M;

with medium coverage (1.2 WITH;

with thick coating (1.45 D;

with extra thick coating (D/d>1.8) - G.

Designation of consumable coated electrode

Letter E- international designation of a consumable coated electrode.

A group of indices indicating the characteristics of the weld metal or deposited metal

For electrodes used for welding carbon and low-alloy steels with tensile strength up to 588 MPa (60 kgf/mm 2).

http://elektrod-3g.ru

For the first time, a welding electrode appeared in 1902. A lot has changed since then new types and brands have appeared. Welding electrode is the most common material. Each brand of electrode has its own properties . You should always remember that for each type of material, you should choose a special electrode.

The most popular brands of electrodes intended for carbon and low-alloy steel: UONI-13/NZh/12x13. Electrodes of this brand are intended for welding corrosion-resistant steels. This model is created according to all the rules GOST 9466-75. Welding with such an electrode occurs on direct current.

SSSI 13/55. This welding electrode is used for welding both low-alloy and carbon steel. Compliant GOST 9466-75,GOST 9467-75,TU 1272002010558589 . The welding process takes place with both alternating and direct current of reverse polarity.

MR-3S .The welding electrode of this brand is intended for welding products made of carbon and low-alloy steel. Welding is carried out using direct and alternating current.

MR-3T. This electrode is intended for welding products made of carbon, low-alloy steel. Welding can be carried out with both direct and alternating current. The polarity of direct current is reversed. But for such electrodes there is one caveat: the carbon content must be at least 0.25%, and the temporary tensile strength must not exceed 490 MPa. Such electrodes comply with GOST 9466-75, GOST 9467-75.

OZS-12. These electrodes are also suitable for carbon and low alloy steel. The tensile strength is 490 MPa. Carbon welding electrodes : VDK VDP SK. Most popular brands tungsten non-consumable electrodes that correspond GOST23949-80: EHF EVL EVI-1 EVI-2 EVT-15 There are also special electrodes for welding copper and copper alloys: OZB-2M OZB-3 ANTs/OZM2 Komsomolets 100 ANTs/OZM3 For welding materials such as nickel and its alloys, electrodes are used: OZL-32, B-56U. If you are going to work with materials such as aluminum and its alloys, then you should choose electrodes: OZANA-1, OZA-1, OZA-2, OZANA-2.

Electrodes play a big role in the welding process. As a rule, welding using electrodes will be more reliable, durable, faster, and more economical.

It's no secret that during metal welding, the electrodes move. These movements are often called oscillatory. There are many technological approaches to performing metal welding work. Electrode During the welding process, regardless of the method used, movement is reported in three different directions.

First movement called translational, in which the movement occurs along the axis of the electrode. Depends on speed melting, translational motion maintains constant length arcs, which should not go beyond 0.5-1.2 electrode diameter. The length of the arc depends on electrode brands and welding conditions. The formation of the seam deteriorates as the arc length decreases, and the possibility of a short circuit (abbreviated as short circuit) arises. An increase in the arc causes an increase in spattering of the electrode metal and a decrease in the quality of the weld in terms of shape and its properties (mechanical).

Second movement is the displacement of the electrode along the axis in order to form a seam. Electrode diameter, current( permanent or variables) and the melting rate of the electrode determine the speed of the electrode. In the absence of transverse displacements of the electrode, the seam is narrow (thread), the width of which is approximately 1.5 times the diameter of the electrode used. This seam is used when welding thin metal sheets.

The last move is to move the electrode across to adjust the width of the seam and the depth of metal melting. These oscillatory movements require a highly qualified welder and his skills, and are also determined by the characteristics of the material being welded, the position and size of the seam. The width of the seam, when using transverse oscillatory movements, varies within 1.5-5 times the diameter of the electrode used.

Competent and technically correct movement of the electrode is the main task and condition for obtaining a high-quality seam when performing welding work. A certain technique for performing oscillatory movements of the electrode, as well as the rationality of its movement, is important. There are several general methods for making a quality seam., applicable in any situation in which the welder performs movements during welding. These are “herringbone” movements (a), angle (b), “spiral movement” (c), “crescent movement” (d). Fig.1

When welding a vertical fillet weld, it is most convenient to show all the methods oscillatory movements of the electrode Moreover, this is a very frequently used operation in welding rolled products. In this case, we will omit all issues related to cutting edges and preparing surfaces before welding.

Using oscillatory movements of the electrode in a crescent or in a spiral, initially the electrode is used to fuse a shelf onto the edges, and then the metal is deposited in small portions without gaps or breaks; it is recommended to weld continuously. Further welding of the metal is carried out gradually with the electrode moving higher, leaving behind a finished welding seam. Another scheme of oscillatory movement during welding - an angle, provides for oscillatory movements of the electrode using an alternating displacement up and down, metal is deposited onto the edges without breaks with a uniform movement of the electrode upwards.

Methodology " herringbone» characterized moving the electrode up, then to the right, after that they descend down to the left along a short trajectory. It is desirable for a drop of metal to solidify at each individual stage of welding between the edges. Afterwards, the withdrawn electrode is moved up to the left and again lowered from the ascent point, but now down to the right. Such gradual movements with continuous separate portions are how the welding seam is made.

Electrodes for welding carbon and low-alloy steels are also characterized by the level of welding and technological properties, incl. the possibility of welding in all spatial positions, the type of welding current, the productivity of the process, the tendency to form pores, and in some cases, the hydrogen content in the deposited metal and the tendency of welded joints to form cracks. The listed characteristics that must be taken into account when choosing a specific brand of electrode are largely determined by the type of coating.

Coverage can be:

Rutilov,

Main

Cellulose,

Mixed.

Acid coated electrodes.

The basis of this type of coating is oxides of iron, manganese and silicon. Weld metal made with acid-coated electrodes has an increased tendency to form hot cracks. According to the mechanical properties of the weld metal and welded joint, the electrodes belong to types E38 and E42.

Acid-coated electrodes are not prone to pore formation when welding metal covered with scale or rust, or when the arc is extended. Welding can be performed with direct and alternating current.

Electrodes with rutile coating.

The coating of such electrodes is based on rutile concentrate (natural titanium dioxide). The weld metal, made with rutile-coated electrodes, corresponds to mild or semi-mild steel. The resistance of the weld metal against the formation of cracks in electrodes with a rutile coating is higher than that of electrodes with an acid coating. According to the mechanical properties of the weld metal and welded joint, most brands of rutile electrodes belong to electrodes of the E42 and E46 types.

Rutile electrodes have a number of advantages compared to other types of electrodes, namely, they provide stable and powerful arc combustion when welding with alternating current, low metal loss due to spattering, easy separation of the slag crust, and excellent weld formation. Electrodes are little sensitive to the formation of pores when changing the arc length, when welding wet and rusty metal and on an oxidized surface.

The electrodes of this group also include electrodes with ilmenite coating, which occupy an intermediate position between electrodes with acidic and rutile coatings. The main component of the coating of these electrodes includes ilmenite concentrate (a natural compound of titanium and iron dioxides).

Electrodes with basic coating.

The basis of this type of coating is carbonates and fluoride compounds. The metal deposited with electrodes with a basic coating corresponds in chemical composition to mild steel. Due to the low content of gases, non-metallic inclusions and harmful impurities, the weld metal made with these electrodes is characterized by high ductility and impact strength at normal and low temperatures, and also has increased resistance to the formation of hot cracks. According to the mechanical properties of the weld metal and welded joints, electrodes with a basic coating belong to electrodes of the E42A, E46A, E50A, E55 and E60 types.

At the same time, in terms of technological characteristics, electrodes with a basic coating are inferior to other types of electrodes. They are very sensitive to the formation of pores in the presence of scale, rust and oil on the edges of the parts being welded, as well as when the coating is moistened and the arc is extended. Welding is usually carried out with direct current of reverse polarity. Before welding, electrodes must be calcined at high temperatures (250-420 0 C).

Electrodes with cellulose coating.

This type of coating contains a large amount (up to 50%) of organic components, usually cellulose. Metal deposited with cellulose electrodes has the same chemical composition as semi-quiet or mild steel. At the same time, it contains an increased amount of hydrogen. In terms of the mechanical properties of the weld metal and welded joints, cellulose-coated electrodes correspond to electrodes E42, E46 and E50. Cellulose electrodes are characterized by the formation of a uniform back seam bead during one-sided suspended welding, and the ability to weld vertical seams using a top-down method.

All electrodes described above, intended for welding carbon and low-alloy steels, with any type of coating, must meet the requirements of GOST 9466-75 and GOST 9467-75, as well as the requirements of technical specifications for electrodes.

The technical specifications may contain additional requirements that are necessary to more efficiently conduct the process and/or obtain welded joints with special characteristics and increased operational reliability.