What electrodes are for welding cast iron

What electrodes should be used to cook cast iron, what brands, how to choose

Cast iron is an alloy of iron and carbon with the addition of impurities and alloying additives. This material is widely used in many areas. Welding cast iron is characterized by several features that must be taken into account when carrying out work. Depending on the structure of the alloy, white and gray cast iron are distinguished. We will consider below what electrodes are needed for welding different types of cast iron.

Preparing cast iron for welding

The fundamental step for successful welding is preparation. It is necessary to weld cast iron after performing the following operations:

• Cracks should be cut , for this purpose mechanical and thermal methods are used. Cutting facilitates sufficient welding of the defect.
• When working with thick-walled parts, proper cutting of the edges will prevent overheating of the product and guarantee uniform heating. The bevel angle should be 45 degrees.
• Welding thin metal requires the use of graphite heat-dissipating pads, which will prevent burning and help maintain the original shape of the product.
• Before the welding process, workpieces must be cleaned of various types of contaminants: dust, debris, rust.
• Massive and heavy products must be fixed with tacks that hold the entire structure.
• Depending on the chosen welding method, the product should be heated to the required temperature. Hot welding involves preheating the workpiece to 600-650°C; semi-hot - up to 400-450°C; cold welding does not require heating the part.

Let's look further at what kind of electrode is needed, depending on the technology chosen.

What electrodes are used for welding cast iron

In this section we will look at what electrodes can be used to weld cast iron. Depending on the tasks assigned and the type of structures being welded, various consumables should be used. So, what brands of electrodes are used to cook cast iron?

1. To carry out work on welding critical structures, special electrodes for cast iron should be used. To prevent the formation of cracks, it is necessary to carry out the connection using the hot method. It is worth highlighting the most popular brands that are used for welding cast iron:

Welding electrodes MNCh-2.

Some brands are universal (MNC-2), others are intended for certain types of work and materials.

to cook malleable cast iron using OZCh-2, OZCh-6, TsCh-4, MNCh-2.

Cast iron be cooked using OZCH-3, OZZHN-1 and OZZHN-2 electrodes.

Also, welders often have a question: what brands of electrodes are suitable for welding gray cast iron ? For work of this type, OZCh-2, OZCh-4, OZCh-6, OZZHN, and also MNCh-2 are suitable.

Among foreign-made rods, OK 92.18 and ZELLER 855 should be highlighted. The first grade is intended for high-strength, gray and ductile cast iron. The second is used for all types; welding can be performed in any spatial position.

[ads-pc-3][ads-mob-3]

which electrode is best for welding cast iron independently after practical application or theoretical comparison.

What electrodes for cast iron look like can be found in the corresponding section of our directory, going there to the pages of individual brands.

2. You can cook cast iron with conventional electrodes , which are also called steel or general purpose materials. The most common rods of this type are ANO, UONI and others.

Conventional consumables are used when performing non-essential work, when welding ordinary structures and in cases where no special requirements are imposed on the weld metal. This is due to the low quality of the weld metal.

The use of steel electrodes allows the contractor to significantly save on materials.

Attention! We do not recommend using electrodes not intended for cast iron, due to the poor quality of the weld. We provide information to familiarize you with the topic from all sides.

3. To correct defects in cast products, cast iron electrodes . These materials are cast rods with a coating: MNCh-1, OZB-2M, OZCh-1. Welding using the listed rods can be carried out using cold and semi-hot methods.

4. Non-consumable electrodes : tungsten, graphite and carbon - are used quite rarely. Their cost is higher than all the listed consumables. The use of rods of these types implies the presence of special conditions. The work process is characterized by an increased level of costs: labor and financial. In addition, certain difficulties may arise during welding. The most common welding method using non-consumable electrodes is AC TIG.

Other useful information is presented in the article “Welding cast iron with electrodes.”

for novice performers to answer the question of how to identify electrodes using cast iron? In practice, this difficulty rarely occurs, since each pack is “equipped” with all the necessary information. The purpose of the rods is also indicated on the websites of sellers and manufacturers.

Experienced performers, in turn, can visually distinguish a cast iron electrode from a regular one without any problems. To avoid having to think about how to distinguish cast iron electrodes from other types of consumables, you should store the materials in packaging. This will not only eliminate questions from arising, but will also keep the electrodes safe and sound.

How to weld cast iron at home

It should also be noted what electrodes are needed for cast iron when welding at home. The choice of consumables when carrying out work at home depends on several factors :

• experience and knowledge of the performer;
• financial opportunities;
• presence or absence of equipment.

Having extensive practical and theoretical skills allows you to make connections using any type of rods listed above.

To save money, it is allowed to use ordinary rods if the quality of the connection does not pose a threat to life and health.

Most often, home craftsmen have an inverter-type device , which has a wide range of advantages. In this case, it is also possible to use consumables of almost any type: special, cast iron or steel. The welder can decide which is best for cast iron after familiarizing himself with the entire range of electrodes.

Other important points are presented in the article “Welding cast iron with an electrode at home.” This information will help determine how to cook cast iron and how to do it correctly.

What electrodes should be used to cook cast iron and steel?

The need to connect products made of cast iron and steel arises quite often. Therefore, it is important to know which electrodes should be used to weld these materials of different structure. The following grades are recommended for welding steel and cast iron:

TsCh-4 is used in cold, semi-hot and hot technologies. Designed to eliminate defects and surfacing. This grade can be used to apply the first layer, so that ordinary rods can be used to fuse subsequent layers.

Ficast NiFe K and ZELLER 855 provide weld metal with similar characteristics: strength; no cracks; easy workability.

Advantages of OK NIFE-CL-A (OK 92.58): the ability to perform welding in any position; Suitable for a wide range of work.

This article will help professional and novice welders find out what electrodes are available for cast iron.

Source: https://WeldElec.com/info/kak-pravilno-varit/chugun/kakimi-elektrodami/

What types of electrodes should I choose for welding cast iron at home?

Cast iron parts are found in industry and everyday life. When connecting parts, electrodes for welding cast iron are used. In order to obtain a high-quality connection, you need to know the technological process and safety requirements.

Electrodes for welding cast iron

Is it possible to cook cast iron?

Craftsmen can determine the weldability properties of cast iron by cutting. If the cut reveals that the material has a fine-grained structure, then connecting the parts will not cause difficulties. However, if the cut material has a large structure, then additional equipment and components must be used during welding. Cast iron that has been exposed to moisture, oil, and an acidic environment for a long time is considered unsuitable for processing.

Cast iron is a metal with limited weldability; when connecting parts, the following material features are taken into account:

• when welding, the workpieces are installed in a horizontal, lower position, since the metal is fluid;
• observe the temperature regime; if violated, defects may form at the seam site;
• as a result of excess temperatures, as well as the low fluidity of cast iron, internal stresses at the weld site may increase;
• When melting, the metal forms oxides that melt at high temperatures.

Cracks may appear on the weld as it cools. To prevent this phenomenon, it is recommended to follow technology.

Features of cast iron welding

The metal has characteristics that influence the joining process:

• rapid cooling leads to the appearance of white cast iron on the surface of the seam, which is not processed and also self-destructs;
• exceeding the permissible processing temperature leads to microcracks in the weld;
• when an electric arc burns, excess gases are formed in the bath, which makes the seam porous;
• Difficulties may arise during formation; molten metal may flow out of the weld pool;
• The material contains silicon; when it interacts with oxygen, a refractory oxide is obtained, and the seam will be uncooked.

Joining cast iron parts may present difficulties, but this does not make metal welding any less common. It is used to process possible defects after foundry production, as well as in the manufacture of complex structures. the characteristics of the material require the use of devices and components (electrodes and wire), on which the quality of the connection depends.

Connecting a cast iron pipe by welding

Cast iron welding technology

In the presence of additional heating, as well as its absence and the temperature of the weld pool, there are three methods of welding cast iron with electrodes:

• hot;
• semi-hot;
• cold.

hot

Used in industrial production. The part is heated to a temperature of 650°C, which is difficult to achieve at home, since you need to have special equipment. As a result, damage to the welding seam is avoided.

During processing, the workpieces should be heated evenly. As a result of temperature differences between the joint and the base metal, a fracture may occur. Before work, the parts are secured, which helps reduce internal stress during heating. It is forbidden to exceed the reading of 750°C, this leads to melting of the material.

Semi-hot

Used in industrial production and private workshops. Heating does not exceed 450°C.

Cold

The master does not preheat the part. In the absence of equipment, as well as for piece repairs and one-time processing, cold welding is used. However, the connection made in this way is of poor quality.

What electrodes should you use to cook?

Types of electrodes:

• alloy steel wire;
• made of carbon material;
• cast iron rods;
• copper rods, as well as manufactured and alloys.

Steel electrodes are coated with a mixture containing ferrosilicon. With its use, the master can obtain gray cast iron at the junction of parts, which differs from its analogues in useful characteristics. This type of electrodes is used to connect parts that are not subject to increased loads during operation.

Brands of electrodes for welding cast iron:

1. EMChS. The electrode core contains low carbon steel. On top of the core there is a coating consisting of several layers, each of which protects the weld pool, generates gas, and improves the properties of the metal. This type of electrode does not require preheating of cast iron parts, the thickness of which should not exceed 10 mm.
2. TsCh4. It is considered an ordinary electrode. The core is coated with a substance that, during operation, enters into a chemical reaction with carbon and forms carbides that do not interact with iron.
3. MNC-1. The core consists of copper and zinc alloys. In this case, the seam is of high quality, it is not subject to destruction, and is easy to process. The amount of dissolved carbon decreases at the weld site.
4. Cast iron. They make two types: barium carbonate and carborundum, which are mixed with a solution of liquid glass.

The components are made from a set of rods:

• copper-iron alloy coated with iron powder;
• copper covered with steel wire;
• copper, covered with tin.

When choosing components, they are guided by the thickness of the metal, the magnitude of the current, as well as the requirements for the seam.

Types of electrodes for welding

How to weld cast iron?

Before joining the parts, it is necessary to prepare the weld area. The metal is removed using a grinding machine, then the joint is wiped to degrease. If there are defects on the edge, they are completely removed. Parts are fixed and heated if necessary.

Welding cast iron with an electrode at home is performed subject to the following conditions:

• the terminals are connected in reverse order;
• rated power is set according to the size of the metal;
• one weld does not exceed 50 mm;
• To prevent critical heating of cast iron, it is recommended to interrupt the electric arc, as when connecting with conventional electrodes.

Compliance with safety requirements and technological process conditions allows the craftsman to obtain a high-quality seam, the joint will not be destroyed in the future.
Welding the cast iron with a secret, the old-fashioned way, everyone can do it!\Welding the cast iron with a secret
Master class on welding cast iron with electrodes

What types of electrodes should I choose for welding cast iron at home? Link to main publication

Source: https://metalloy.ru/obrabotka/svarka/elektrody-dlya-chuguna

Electrodes for welding cast iron: types, types, characteristics and features

It often happens that it is necessary to weld parts that are made of cast iron. This type of welding is one of the most difficult and requires knowledge and experience to perform it.

In order to perform welding efficiently and to ensure smooth welding seams, it is necessary to properly select electrodes for cast iron.

This article was written to introduce you to welding cast iron parts. Let's look at the chemical composition of cast iron and what types of electrodes are used in this case.

Characteristic properties when welding cast iron

The iron-carbon alloy is called cast iron. Carbon is added to an iron alloy to increase hardness and reduce ductility.

Its content is approximately 2.14%. This connection gives the alloy lightness and makes it more resistant to adverse environments.

This also reduces the likelihood of corrosion. To achieve high durability, the alloy undergoes an alloying process. This is the process of adding impurities to the composition of materials to improve the properties of the base material.

In this case, it could be: aluminum, vanadium, chromium, nickel and others.

Without the addition of these impurities, cast iron becomes very brittle.

There are the following types of cast iron:

• white cast iron is the hardest and most brittle, and therefore responds poorly to welding.
• gray cast iron is softer due to the addition of silicon (from 1.2-3.5%) and carbon. This type of cast iron responds well to welding.
• Malleable cast iron is formed by prolonged annealing of white cast iron. The output is flake-shaped graphite. This type of cast iron is the most ductile and tough.

Obstacles encountered when welding cast iron parts

The carbon contained in cast iron complicates the welding process. Therefore, it is worth choosing the type of electrodes responsibly.

Circumstances that make welding cast iron difficult:

• When welding cast iron parts, enough gas is generated, resulting in bubbles that contribute to the formation of cracks in the weld. In case of insufficient cooling, the seam will lose its strength due to increased porosity.
• When welding parts made of very thin cast iron, you need to be extremely careful, since due to exceeding the permissible temperatures, the parts may simply fall apart.
• glow, which can arise due to violation of welding rules, is very difficult to remove from cast iron parts.
• since the melting point of some oxides that are included in the composition is very high, some parts may be difficult to weld. Therefore, a film may form between the material and the melt. If it occurs, then considerable effort must be made to remove it.
• the temperature of the alloy that is in the weld drops very quickly. As a result, cementite is formed. It gives a white color to the parts being welded and is difficult to process.
• It is also possible for the melt to leak from the weld seam.

The procedure for welding work with cast iron parts includes:

• Before starting work, it is necessary to clean the surface to be welded and remove the oxide film if it has formed.
• edge grinding is one of the important stages. Because if there are cracks on the surface, then during the welding process you can expect mass leakage from the weld seam. To prevent this situation, a mold with graphite inserts is used. It can be made using sand.

Note! To avoid a situation where the molten mass flows out through existing cracks, which can harm the person doing the work, it is necessary to use a graphite insert. It can be assembled from refractory bricks.

Proper warming up

To warm up the workpiece, you need to make an effort. The temperature at which cast iron melts ranges from 1150 Co to 1200 Co, which is 300 Co lower than that of iron without impurities.

Based on this, the workpieces are preheated to 500-700 Co. You need to approach this stage with caution, since you need to warm up both the parts that will be welded and the area around it. If the heating is carried out correctly, the metal will not crack.

When performing professional work, special devices are used for heating - crucibles. When performing welding work at home, you can use a gas torch.

To get a positive result, it is better to do such work together. This way, one will be able to carry out and control the heating of the surface, and the second will perform welding.

After the welding process is completed, you need to lower the temperature of the workpiece. To do this, it can be placed in ordinary sand. To reduce the likelihood of cracking, you need to cool it for as long as possible.

Note! To prevent hand burns, all work should be done in gloves that have additional heat protection. You should not neglect the use of a reflective shield so as not to burn the retina or face and neck. In case of burns, you must contact a medical facility for proper diagnosis of the degree of burn and qualified treatment!

At home, it is quite difficult to reach a temperature of 600°C in order to carry out welding work at high temperatures. Therefore, most often, semi-hot welding is used, for which a heating temperature of up to 400C is sufficient.

This method is used if it is necessary to perform work on important parts. In any other cases, you can use the cold welding method.

When performing hot welding, the lower part of the welded surface can be cooled with water. There is a special product, the use of which prolongs wear resistance. This is castolin, it is applied to the weld seam after welding.

Main types of electrodes for welding cast iron and their features

Among the electrodes for welding cast iron, the following main types of electrodes are distinguished:

• EMChS type electrodes. These electrodes are made from a special wire that contains carbon in small quantities. They consist of three layers. The first is a gas-forming layer, promotes the formation of a protective layer of the melt and prevents the formation of bubbles, the second is a slag-forming layer, it protects the weld pool from oxidation.
• alloying. It improves the chemical and physical characteristics of the material being welded. Electrodes of this type are most productive when welding cast iron parts up to 1 cm thick. The peculiarity is that at the beginning of welding there is no need to heat up the parts.
• electrodes type TsCh-4. This type is especially famous. Their thickness is 3 – 5 mm. They contain chemical elements that, at high exposure temperatures, contribute to the formation of a first-class welding seam. Initial heating is also optional. For 1 kg of deposited metal, the consumption of such electrodes will be only 1.8 kg.
• electrodes type OCHZ-1. The basis is an iron-copper alloy, which is coated with iron powder with an admixture of UONI-13. Additional components in the composition include liquid glass. Such electrodes make it possible to effectively perform welding work in vertical, horizontal and ceiling positions.
• electrodes that do not melt during the welding process. This type of electrode is characterized by the use of tungsten, carbon or graphite rods fed by a special cast iron wheel or wire. These include coal, graphite and tungsten.

Having reviewed the information presented, we can say that welding cast iron surfaces is a rather difficult type of work. To simplify these types of work, it is necessary to select the right type of electrodes to obtain a satisfactory result.

Source: https://prosvarku.info/elektrody/ehlektrody-dlya-svarki-chuguna

Welding: types of electrodes and rods for welding cast iron, main difficulties - Machine

page » About welding » How to cook correctly » How to cook cast iron » Welding cast iron with electrodes

Cast iron is an alloy of iron and carbon (content exceeds 2.11-2.14%), which contains impurities: silicon (no more than 3%), manganese (up to 1%), sulfur, phosphorus and alloying additives: chromium, nickel , vanadium, aluminum, magnesium and others. Without special additives and heat treatment, cast iron has low strength, hardness and ductility .

Carbon may be present in the alloy in the form of cementite and graphite. Depending on the proportion of these substances in the composition, several types of cast iron can be distinguished.

Some of them can be processed by welding, others cannot. For each type of alloy there are certain brands of electrodes. Next, we will look at which cast iron is welded with electrodes in various situations.

White cast iron is characterized by the fact that all carbon is present in the alloy in the form of cementite. This type has high hardness and cannot be processed with cutting tools.

Most or all of the carbon is present in gray cast iron in the form of graphite. This type lends itself well to processing; has high casting properties, thanks to which it is actively used as a material for casting. Welding of gray cast iron with an OZCH-2 electrode is performed with direct current with reverse polarity.

Also for this type are the brands OZCh-4 and OZCH-6, OZZHN-2, MNCh-2.

Malleable iron is the result of casting and heat treating white iron to form flake graphite; used in the production of cars, tractors and agricultural machinery. Electrodes designed for working with malleable alloy: OZCh-2 and 6, MNCh-2, TsCh-4. Welding is carried out with direct current; the polarity when welding cast iron is reversed.

• In half cast iron, carbon is present in two forms: graphite and cementite; used in the manufacture of parts operating under conditions of increased wear resistance.
• Ductile iron contains nodular graphite, which is formed during the crystallization process; used for the production of critical parts in mechanical engineering, as well as for oil and gas pipelines, water supply pipes.
• In the article we will look at how to weld cast iron with electrodes, depending on the connection method used.

Difficulties in welding cast iron

Before starting work, the contractor must take into account the features of welding cast iron with electrodes. These specific features are due to the unique properties of cast iron.

One of the main disadvantages of cast iron is poor weldability, which is due to the following factors:

• poor connection of cast iron by welding is explained by its chemical structure and properties; In the photo: time in the welding bead
• Various elements, in particular silicon, are oxidized in the weld pool, resulting in the formation of oxides. The refractoriness of these oxides leads to the appearance of uncooked areas ;
• rapid cooling of the joint and heat-affected zone leads to the formation of areas of cementite characterized by increased hardness. These areas are difficult to machine ;
• cast iron is characterized by high fluidity , which makes it difficult to retain the molten metal in the bath and complicates the formation of a seam;
• uneven heating and cooling of brittle cast iron can most likely lead to cracks ;
• molten cast iron tends to release gases, which can cause pores .

Despite these difficulties and features, a performer of any level can obtain a high-quality and reliable connection. To do this, you need to select the right consumables. We will discuss below which electrodes to choose for welding cast iron.

Methods of welding cast iron

There are three methods of welding cast iron, depending on the preheating temperature of the products:

Hot welding is the main and most “correct” method. Before welding, the workpieces are heated to a temperature of 600-650°C.

Semi-hot welding involves heating cast iron parts to a temperature of 300-350°C.

Cold welding does not involve heating the workpiece.

When using different types of cast iron welding, the types of electrodes also differ. Regardless of the method chosen by the performer, the rules and recommendations should be strictly followed. This article is devoted to how to properly cook cast iron with various types of electrodes.

[ads-pc-2][ads-mob-2]

Cold welding of cast iron with special electrodes

Welding electrodes MNCh-2.

Cold welding is simple and easy to perform. The connection is made using special electrodes containing nickel and/or copper. There are quite a lot of special rods of this type. The most popular brands made by domestic manufacturers are:

• the basis of the OZCh-2 and OZCh-6 electrodes is a copper rod coated with a coating that includes iron powder;
• nickel and iron-nickel consumables OZZHN-1, OZCh-3, OZCH-4, with the help of which welding of cast iron is carried out with direct current.
• iron-copper-nickel MNC-2. Welding cast iron with MNC 2 electrodes allows you to obtain a high-tech weld that is corrosion resistant in liquid aggressive media and hot gases. This brand has a fairly high cost, so it is used mainly for critical work and in cases where strict quality requirements are imposed on the connection.

Or watch a presentation on cold welding cast iron with the Zeller 855 electrode. These are really very good electrodes, but they are expensive and difficult to buy.

How to cook cast iron using electrodes on cast iron will be discussed below.

Basic principles. Welding with electrodes on cast iron can be performed in vertical and lower spatial positions. In this case, direct current is used.

There is also one more rule - try to stick to a small penetration of the base metal. To do this, it is necessary to use small current values, small diameter rods and short seams.

After applying each seam, you should take a break to cool the part to 50-60°C.

Welding with all the listed brands of electrodes is performed using direct current. To determine which polarity to cook cast iron with, you should familiarize yourself with the technical characteristics of consumables, all brands of which are collected on the corresponding page.

Welding cast iron with simple electrodes (on steel)

Welding cast iron with conventional steel electrodes does not provide good weld quality . Consumables of this type are used due to their availability and low cost. To reduce the negative consequences of using steel electrodes, it is necessary to use special TsCh-4 rods. This brand is one of the most popular and in demand among welders.

Therefore, it is important to know how to properly cook cast iron with TsCh-4 electrodes. This grade is intended for surfacing the first cladding layers with subsequent continuation of the welding process with conventional materials (in the picture). In addition, TsCh-4 is suitable for both hot and cold welding of cast iron, sealing defects and joining steel to cast iron .

As for the SSSI. Often performers wonder about UONI electrodes, whether it is possible to cook cast iron with this brand. It should be noted that conventional electrodes can only be used when welding small defects in non-critical structures.

Since the quality of the connection will not be high. To obtain more or less satisfactory quality, you should follow the same rules as when welding with special electrodes.

Another effective way to improve the quality of the connection is a slight preheating to 150-200°C and slow cooling.

Welding electrodes "UONI-13/55" in packaging.

When welding cast iron with general purpose electrodes, the weakest point is the heat-affected zone at the fusion boundary. This zone is characterized by fragility and the presence of cracks. These defects often lead to peeling of the deposited layer from the base metal. To avoid this, you must use steel studs or bolts.

The studs are threaded and screwed into the surface to be welded. The dimensions depend on the thickness of the work product. There are recommendations regarding stud sizes:

• the diameter should be 0.3-0.4 of the thickness of the part, but not more than 12 mm;
• screw-in depth - 1.5 times the diameter of the stud, but not more than half the thickness of the products being welded;
• the height of the protruding part of the pin is 0.75-1.2 of its diameter.

The studs are placed in the beveled edges of the parts in a checkerboard pattern at a distance of 4-6 diameters .

The protruding parts of the studs are scalded around the perimeter, gradually filling the seam. First of all, all studs are welded with circumferential seams using electrodes whose diameter is 3 mm.

A low voltage is used. Welding is done randomly to avoid severe overheating.

Afterwards, circular seams are placed around the welding site until the entire surface is covered with a layer of deposited metal.

We hope that presenting here the above rules and recommendations will help you figure out how to weld cast iron correctly with electrodes and successfully complete the work.
[ads-pc-3][ads-mob-3]

Welding cast iron with non-consumable electrodes

Cast iron can be welded with different types of non-consumable electrodes: tungsten, carbon or graphite. Cast iron or special filler rods containing nickel, aluminum, copper and other metals are used as filler material.

To protect the welding zone, inert gases are used, most often argon or fluxes, the main component of which is borax. The most popular technology is AC TIG - welding with a tungsten electrode using alternating current in an argon environment.

Welding cast iron with coated electrodes

Cast iron electrodes are special materials for correcting defects in cast iron, which are cast round rods coated with different compositions. In most cases, the connection is made using direct current, but it is also possible to use alternating current. The current value is determined at the rate of 50-60 A per 1 mm. electrode.

The quality of the seam obtained as a result of cold welding with cast iron electrodes is heterogeneous. Therefore, semi-hot welding should be performed.

1. How to properly cook cast iron with electrodes, the video is presented below.
2. After reviewing the entire range of information, the performer will be able to choose the best electrode for cast iron.

Electrodes for surfacing cast iron

• MNC-2;
• OZHN;
• OZCh-2;
• TsCh-4.

Surfacing cast iron with T 590 electrodes also guarantees a high-quality connection. This brand is widely used in various fields of activity, for working with different structures and parts. The affordable price of T-590 rods makes these consumables so popular among welding professionals.

More detailed information is presented in the article “Metal surfacing: electrode and others.”

This article will help every performer find out what are the best electrodes for cast iron.

Source: https://regionvtormet.ru/svarka/svarka-vidy-elektrodov-i-sterzhnej-dlya-svarki-chuguna-osnovnye-slozhnosti.html

How to make electrodes for cast iron at home

How to make electrodes for cast iron at home

The carbon contained in cast iron makes it difficult to weld. If the approach is incorrect, deep pores and cracks may appear at the joint, and in general, the workpiece being welded can easily be damaged.

For this reason, there are special requirements for welding cast iron, one of which is the use of the appropriate type of electrodes. Electrodes for cast iron differ in materials of manufacture. They can be made from cast iron rods, steel wire, and copper and its alloys.

This article from the website about MMA welding mmasvarka.ru will talk about what types of electrodes for cast iron exist, and whether they can be made with your own hands, so to speak, at home.

Types of electrodes for welding cast iron

Special types of electrodes are used for welding cast iron products. If steel wire was taken as the basis for their manufacture, then cast iron electrodes are marked as follows - SV-08 A and SV-08. There are also so-called universal types of electrodes for cast iron.

TsCh-4 - with electrodes of this brand you can obtain an even and strong welding joint on cast iron and products made from it. TsCh-4 electrodes are suitable for welding at almost any temperature.

EMChS - for their manufacture, low-carbon wire is used, on which a three-layer coating is applied during the manufacture of EMChS electrodes. Due to this, during the combustion of the electrode, a gas protective layer is formed, which protects the weld from the formation of air bubbles and oxidation.

Ficast NiFe K electrodes are a special type of electrode for welding cast iron and steel together. They are iron-nickel rods for high-quality welding of cast iron and steel.

MNCh-1 - electrodes of this series are made of an expensive alloy, which includes: copper, nickel and monel metal. Thanks to the use of these electrodes on cast iron, the seam is easy to further process, and no pores or cracks form on it.

How to make electrodes for cast iron with your own hands

The cost of electrodes for welding cast iron is quite high, and today it is quite difficult to find high-quality consumables for working with cast iron and products made from it. Therefore, many experienced welders resort to one trick: they make cast iron electrodes themselves.

To make them, you will need copper wire up to 2 mm, and the most common electrodes for welding, for example, the same UONI, ANO-4 or UONI 13/45. The process of converting conventional electrodes for welding cast iron is very simple. To make electrodes for cast iron with your own hands, you will need to wind copper wire onto ordinary electrodes. Thus, using ordinary electrodes, it will be possible to cook cast iron.

An equally popular method of making electrodes using cast iron and using the following components:

• Liquid glass;
• Copper rods, up to 5 mm in diameter;
• Metal powder and crushed electrode coating.

The process of making homemade electrodes for welding cast iron using these components is as follows:

• Copper rods are cut to the required length, after which they are thoroughly cleaned with fine sandpaper and degreased;
• A previously prepared and carefully crushed electrode coating is taken and mixed with fine metal filings (proportions: one to one). Then approximately 30% liquid glass is added to the resulting mixture;

• Next, cut copper rods are taken and dipped several times into homemade electrode coating until their coating becomes approximately 2 mm thick;
• The electrodes are then dried;
• And before welding cast iron, homemade electrodes are always calcined in an electric oven. The temperature for calcining electrodes on cast iron is approximately 200 degrees plus.

As you can see, making electrodes for welding cast iron is not at all difficult. Thus, you will not only save on consumables for welding, but also achieve better quality of work.

Good luck to you! Subscribe to the MMA welding in Zen channel and stay up to date with the latest news!

Source: https://mmasvarka.ru/elektrody-po-chugunu.html

What types of welding electrodes are there for cast iron?

Along with steel, cast iron is the main structural material. However, due to its physical and chemical composition, it has a lot of features that should be taken into account when welding. In addition, there are several types of cast iron, which also needs to be taken into account when choosing welding consumables. What types of welding electrodes are there for cast iron? First, let's look at the specific properties.

1. Features of cast iron

2. The best electrodes for cast iron

3. Cold welding of cast iron

4. Hot welding of cast iron

5. Main brands of electrodes for cast iron

Along with steel, cast iron is the main structural material. However, due to its physical and chemical composition, it has a lot of features that should be taken into account when welding. In addition, there are several types of cast iron, which also needs to be taken into account when choosing welding consumables. What types of welding electrodes are there for cast iron? First, let's look at the specific properties.

Features of cast iron

Unlike steel, cast iron contains a significant amount of carbon - from 2 to 6%, while CO2 is in a free state - in the form of graphite. This determines its unique characteristics - it is extremely hard, but at the same time fragile, has low ductility and viscosity. These properties affect the processing and welding of metal. If the parameters, materials and welding techniques are incorrectly selected, the following risks exist:

• due to the presence of graphite in the metal, cracks may form;
• carbon burns out, which leads to the formation of pores in the weld;
• Refractory oxides are formed, whose melting point is higher than that of cast iron.

In addition, difficulties during welding can be caused by such a property as high fluidity, which prevents the formation of a high-quality seam.

Rapid cooling of gray cast iron after a heating temperature of more than 750°C leads to the transformation of graphite into iron carbide - cementite. The cast iron itself turns from gray to white. Such cast iron cannot be welded.

The best electrodes for cast iron

These features require the selection of special brands of electrodes. They must provide the same concentration of CO2 in the base and filler metal and the same cooling time.

Electrodes for cast iron often include copper (copper-nickel, copper-iron electrodes), but they can also be steel, ferro-nickel or nickel. The type of rod coating is basic, less often acidic. Among the most popular grades that are used for welding on cast iron are MNCh-2, OZCh-4, OZCh-6, OZCH-2, OK 92.18, OZZHN-1.

Some of them are universal in purpose, allowing you to work with all types of cast iron (except for the white one mentioned above), some have a narrower specialization (more on this below).

Electrode brand	Cast iron type	Welding direction	Welding type	Properties
MNC-2	in the bottom vertical from bottom to top semi-ceiling positions	cold welding of casting defects surfacing of parts	Preferred for welding the first layer in joints that require high joint density and surface cleanliness after processing
TsCh-4	grey malleable  high strength	in the down position	cold and hot welding for damaged parts welding of defects	For structures made of ductile iron with nodular graphite and gray cast iron with flake graphite, as well as their combinations with steel.
OZCH-6	in the bottom vertical from bottom to top	For manual arc welding and surfacing of thin-walled parts.
OZCH-4	in the bottom vertical from bottom to top	warm welding (hourly calcination at a temperature of 250-280 °C)	They are preferred when welding the last layers, providing the weld metal with high abrasion resistance and impact strength.
OZCH-2	in the bottom vertical from bottom to top	cold welding	For welding, surfacing and welding of casting defects when restoring cast iron products.
OZZHN-1	in the bottom vertical from bottom to top	cold welding	This grade is often used for welding large casting defects and multi-layer surfacing with large volumes of metal.
OK 92.18	grey malleable high strength	all provisions	hot welding	They have proven themselves well in the repair of products made from thin parts (welding damage and defects in gearboxes, pump housings, engine blocks, etc.).

Cold welding of cast iron

Cold welding is the welding of cast iron without preheating the parts.

Cold welding requires special electrodes. This includes brands such as MNCh-2 (good for welding parts in critical structures), OZCH-2, OZCH-6 (especially effective when working with thin-walled products), TsCh-4, as well as OZZHN-1 (elimination of serious defects).

Hot welding of cast iron

Hot welding is welding that requires pre-calcination of the cast iron.

Actually, the “hot” method is the one in which the metal is heated to a temperature of +500 + 600 °C, “semi-hot” - the temperature reaches +300 +400 °C, “warm” - +200 °C. Most often, universal electrodes of the TsCh-4 brand are used for this, as well as OK 92.18 (“warm” method) and OMCh-1. Also in this case, electrode rods of the UONII, ANO brands, carbon and other electrodes are used.

MNC-2

Universal nickel-copper electrodes that allow you to work with any type of cast iron - malleable, gray and high-strength. Products of this brand are specially designed so that welding can be performed without pre-calcination.

The core is made of monel metal (mostly nickel, 28.5% copper, iron and manganese are also present) has a special coating. Main purpose: cold welding, surfacing, welding of casting defects.

Welding is possible in any spatial position except the ceiling and from top to bottom, and is carried out with direct current of reverse polarity. In addition to versatility of use, there are a number of advantages:

• no need for calcination - minor heating is required only when working with thick products;
• easy ignition, stable arc combustion, high melting rate at a relatively low temperature, easy separation of the slag crust;
• excellent quality of the resulting seam in terms of strength, ductility, corrosion resistance;
• color identity of the base and deposited metal;
• low hardness of the seam, due to which during operation of the structure the risk of cracks in the joint area is minimal.

This brand of cast iron electrodes for electric arc welding is widely used in the repair of worn parts in gears, pumps, gearboxes, excavator buckets and other components and mechanisms. Analogues of the MNC-2 brand according to the international classification are electrodes of the ENiCu-B type.

Important. If multi-layer surfacing is carried out, the bead must be gradually cooled to a temperature of 60 ° C and forged with light blows of a hammer. This reduces the internal stress in the metal structure and reduces the risk of cracks appearing in the heat-affected zone. The length of the welding roller itself is from 30 to 50 mm.

OZCH-4

In terms of their properties, these electrodes with a basic coating are almost as universal as the MNCh-2 brand - they can be used to weld any type of cast iron.

Electrodes make it possible to obtain a seam with increased wear resistance (which is important if the operation of the product involves constant friction of metal on metal), as well as high manufacturability during cutting and high resistance to impact loads. For welding and surfacing, reverse polarity current is used. Possible spatial positions are lower and vertical.

When welding technology, one must comply with the requirements for products of the MNCh-2 brand (cooling and easy forging of the roller), however, unlike MNCh-2, in this case, preliminary calcination for an hour at a temperature of 250-280 ° C is necessary.

Important. OZCH-4 electrodes are most effective when welding the last layers, providing the weld metal with high abrasion resistance and impact strength.

TsCh-4

Basic coated electrodes designed for both hot and cold welding of ductile, ductile and gray cast irons. The main purpose is welding of defective castings, surfacing when repairing cast iron parts.

These are also electrodes for cast iron and stainless steel; they allow high-quality welding of these two alloys with different structures.

Often, to obtain a more effective result, they are used only for surfacing the first layers, after which it is performed with other, special electrodes.

OZCH-2

These are copper electrodes for welding cast iron (copper core) with an acid coating. They have a limited scope of use - they are used only for working with malleable (soft and viscous) and gray cast iron. The scope of work includes cold welding, as well as surfacing and welding of casting defects when restoring cast iron products.

The length of the roller that is recommended for welding is small, in the range of 30–50 mm. The resulting roller must be cooled to 60 °C and then forged with gentle hammer blows. Before welding, the electrode should be calcined for an hour at a temperature of 190-210 degrees.

Welding is permissible in the lower and vertical positions with direct current of reverse polarity.

OZZHN-1

Area of ​​use: exclusively cold welding. A constant current of reverse polarity is used. The types of cast iron to be welded are ductile and gray. Before welding, the electrode must be calcined for an hour at a temperature of 350°C.

As is the case with other grades of cast iron, the bead should be forged with light blows of a hammer to relieve internal stress in the weld metal. This grade is often used for welding large casting defects and multi-layer surfacing with large volumes of metal.

In the latter case, these electrodes must be combined with MNCh-2 or OZCh-3 (the first and intermediate layers are fused with them).

OK 92.18

The new name for these electrodes is OK Ni-Cl. They have a base coating with a high graphite content. Designed for welding with minimal heating. They operate on both direct and alternating (at the same time reduced) currents.

They have proven themselves well in the repair of products made from thin parts (welding damage and defects in gearboxes, pump housings, engine blocks, etc.).

Answering the question of which electrodes are suitable for welding cast iron and steel, we note that along with TsCh-4 these are also suitable.

How much do electrodes cost for cast iron?

The main factors that determine the cost of this consumable are the brand and country of origin, the type of electrodes, their brand and coating composition.

Traditionally, high-quality European and American analogues are considered more expensive - for example, products from such well-known brands as ASPIK or UTP.

Excellent consumer properties when working with cast iron are demonstrated by the German-made UTP 86 FN electrode and also by German Capilla brand products. Russian analogues are cheaper, while the quality of modern domestic products is at a high level.

Where can I buy electrodes for cast iron?

Of course, it is worth buying such products only from well-known manufacturers and trusted suppliers - this is a guarantee of high factory quality and, importantly, this is the reputation of the brand. This, and only this quality, is the quality of cast iron electrodes produced by the oldest specialized enterprise in Russia - the Magnitogorsk Electrode Plant.

Electrodes for cast iron

Source: https://magelectrod.ru/article/luchshie-ehlektrody-dlya-svarki-chuguna/

How to weld cast iron with an electrode at home

The service life of cast iron is twice as long as that of steel, however, due to the high carbon content, repairs by conventional electric welding of parts made of this material are ineffective. Microcracks form at the junction, and pores form at the seam. In industry, this problem is solved by special training, which is not applicable for welding cast iron at home. However, creating strong connections is also possible with self-repair using electrodes for welding cast iron.

Welding methods

Three methods have been developed to create strong seams:

1. Hot welding technology is complex, but practically eliminates the formation of cracks. It is performed with preheating to a temperature of 600 - 650⁰C with subsequent slow cooling. In production, this procedure is performed on induction installations. Some beginners doubt whether it is possible to cook cast iron using this method on their own. This is possible if you use a forge, gas burner, or blowtorch for heating, and hot sand for slow cooling.
2. Semi-hot welding is similar to the previous method, but the heating temperature is 300 - 350⁰C.
3. Cold welding is carried out with special electrodes without preheating the parts. However, in order to brew cast iron using this method, it is necessary to take into account the technological features of the material.

Selecting electrodes for welding cast iron

When cold welding, inexpensive electrodes with an index of 2 to 6 are most often used. The basis is copper rods with a special coating. The MNCh-2 grade is used for surfacing metal; an alloy is used to make rods, to which nickel, manganese, iron, and copper are added. These electrodes are scarce and expensive. Cheaper ones include TsCh-4 and OZZHN-1.

Source: https://svarkaprosto.ru/tehnologii/svarka-chuguna-elektrodom

Electrodes used for welding cast iron

Often in everyday life you have to deal with situations when it is necessary to weld products made of cast iron. Such work is labor-intensive and not every welder can cope with it.

One of the most important conditions for a high-quality connection is correctly selected electrodes for cast iron.

In the article we will look at the features of welding this material and how to choose suitable welding electrodes for the job, and also answer the question: what electrodes should be used to cook cast iron?

 Distinctive features of welding cast iron

Cast iron is a material that is an alloy of iron and carbon.
Due to the combination of such elements, it is quite light, durable and not subject to corrosion processes. In order for the material to have such characteristics, it is necessary to alloy the alloy. To do this, chromium, nickel, aluminum, magnesium and other metals are added to cast iron.

If these substances are not added, the cast iron will be brittle and weak.

Currently, there are two types of cast iron:

• white, it gives absolutely no reaction to welding work due to its hardness and brittleness,
• gray, this material is quite soft. By and large, in this case, welding will be the processing of malleable cast iron; it lends itself well to welding.

Difficulties encountered when welding cast iron

It is very important to approach the choice of carbons for welding cast iron responsibly, since during the work you will have to face a number of difficulties due to the high carbon content in the alloy:

• in the process of creating a seam, cracks and pores will constantly appear, this is due to the fact that when welding cast iron a lot of gas is released, so there are a lot of bubbles in the melt. If you do not maintain a balance in the cooling rate, the seam will be porous, and this negatively affects its strength,  

• if thin cast iron is welded, you should be very careful, because if it is overheated, it will crumble,
• various hardened structures can form that are difficult to remove from the surface of the material,
• due to the fact that refractory oxides are present in the weld pool, some places may not be welded through. This is due to the fact that the temperature at which the oxides melt is very high, and therefore the arc may simply not melt. The result is that a film appears between the base material and the melt, which is difficult to remove mechanically.
• in the weld area the alloy cools very quickly. Hard zones with the release of cementite form near the treated area. These places acquire a white tint and are very difficult to process after welding is completed.
• there is a high probability that the melt may leak out of the weld area.

When welding cast iron at home, do not neglect the following recommendations and specialists and try to follow the work technology as accurately as possible.

1. First of all, it is necessary to prepare the surface of the product, it must be well cleaned, and it is also worth getting rid of the oxide film.
2. Next you need to sand the edge. If you see that the material has cracks, chips, or irregularities, then know that during the welding process the mass may simply leak out of the seam. That is why be sure to use special forms with graphite inserts. This form can be made using sand.

Advice! In the area where the mold will be in contact with the welding site, it is better to lay a graphite insert, which can be made from refractory bricks. This way you will protect yourself from unwanted leakage of the melt through the crack.

3.Next we move on to the most labor-intensive process - heating the workpiece. Cast iron melts at a fairly low temperature of 1200-1250°C. In this regard, the preheating temperature should not be higher than 500-700°C. You also need to very carefully warm up both the connection area itself and the space around it. Thanks to this procedure, the metal will not crack.

In industrial conditions, heating is carried out in special crucibles. You can use a gas burner at home or in the garage. It is better to do the work with a partner. One is engaged in warming up the connection area, the other is working with the device.

4.After the welding is completed, the workpiece must be cooled: to do this, it is covered with sand or fine charcoal. The longer the workpiece cools, the less likely there will be cracks and cement release.

Note! To avoid getting burned, perform the entire work process wearing gloves with increased heat protection, and also use a holder with a reflective shield.

Carrying out full-fledged hot welding with heating up to 600°C at home is not easy. Therefore, you should limit yourself to the semi-hot method, which involves heating the part to 300-400°C.

This method is most often used to repair load-bearing structures or connect critical parts. In all other cases, the cold welding method is suitable. When joining workpieces, the seams are laid sequentially, one layer after another.

The part to be welded can be cooled with water from below. It is worth noting that the electrodes for cold welding of cast iron and for hot welding are no different.

After completing the work, to improve the quality of the seam, apply castolin to it - a special composition that will increase the service life of the product.

Electrodes for welding cast iron

The widespread use of cast iron for the manufacture of various parts required the development of methods for their repair. Conventional, well-known methods did not give the required results. This is due to its specific structure and physical properties. This required the development of completely new electrodes for welding cast iron.

Methods and features of welding cast iron

Distinctive features of the welding process are:

• after completion of the work, there is a rapid drop in temperature in the area of ​​the created seam;
• formation of refractory oxides;
• high turnover rate;
• it is not possible to create uniform heating;
• when overheated, the formation and intensive release of various gases occurs;
• the presence in its composition of silicon and other elements capable of forming refractory oxides, which cause the appearance of weakly cooked areas or even lack of cooking.

Currently, three methods have been developed to take into account these features:

• hot method (with preheating);
• semi-hot;
• cold (without preheating).

Each of these methods is used to solve individual practical problems. The first is used mainly in heavy industry. To implement it, you need special equipment that allows you to heat the product to a high temperature.

The main limitation in this method is maintaining the required temperature and preventing it from entering the melt stage. Which leads to a change in the structure of the metal and the formation of new cracks.

Once the process is complete, cooling should be done slowly and naturally.

The second welding method (semi-hot or with preheating) involves heating the parts being welded to a temperature of 300 degrees with the gradual introduction of graphitizing substances into the fire zone. Aluminum or silicon are used as such elements. They ensure high quality of the resulting seam.

To improve the quality of the weld when using these methods, preliminary exposure to the workpiece is used:

• alloying with the help of so-called graphitizers (allowing the internal structure to be stabilized during the cooling process);
• alloying to obtain a pearlite-ferrite structure, this is especially necessary when welding cast iron with low-carbon steel;
• adding oxygen-containing components to increase the degree of oxidation (burning) of carbon, which helps to obtain a weld from low-carbon steel;
• adding non-ferrous metal alloys (for example, copper-nickel, copper-iron, and so on, having a melting point close to cast iron), which increases the ductility of the weld.

Cold welding of cast iron (without preheating) involves precise control of the parameters of the welding arc and the edges of the metal being welded. It is advisable to use this method for products in which the seam length does not exceed 25 mm. The implementation of all three methods is carried out using the following processes:

• manual arc welding (using the required electrodes);
• semi-automatic;
• argon-arc.

The following types of electrodes are used for them: cast iron, with a copper base, nickel rod, steel core.

Modern manufacturers offer a wide range of products for welding. The optimal selection is made based on an assessment of the following parameters:

• what material is planned to be welded (only cast iron blanks or cast iron with another metal, such as steel);
• metal grade;
• what method do you plan to weld cast iron;
• goals and tasks to be solved (welding of two separate parts, surfacing, welding of defects in casting);
• manufacturer reliability;
• price.

After analyzing these provisions, you can accurately select the required brand. Professionals advise choosing electrodes for welding cast iron based on existing standards, recommendations and experience in carrying out such work.

Marking of electrodes on cast iron

Modern standards specify different types of welding products for use. They indicate which brands are suitable for which welding conditions. The marking consists of two components. The first is a set of capital letters, each of which allows you to decipher the composition. The capital M indicates the presence of copper in its composition, the letter H indicates the presence of nickel.

The last letter explains what metal it is intended for, for example the letter H is cast iron. The subsequent set of numbers indicates the brand in the proposed series. In some cases, an abbreviation is added to the marking to clarify the specific affiliation. For example, the letters UD indicate the need for their use for welding carbon and low-alloy steel.

Popular brands of electrodes for welding cast iron

Theoretical developments and many years of experience in welding work with cast iron products have made it possible to identify certain brands that allow us to most effectively solve the problem.

Electrodes for hot welding of cast iron

To implement this method, it is assumed to obtain a temperature of 600 degrees Celsius for cast iron. Products with the designation TsCh-4 are considered the most acceptable. They provide high quality welding of cast iron to steel. At the same time, the metal does not lose its original properties. Nickel ones have proven themselves well, for example, OK 92.18.

Such a sample is a guarantee of high quality and reliability of the resulting seam. It is based on a nickel core. A distinctive feature is the small amount of slag that is formed during welding. Added nickel allows you to obtain the best toughness in the deposited metal. It can be processed quite easily in the future.

In production, samples with the addition of copper are used. These include products of the UONI-13/45 or K-5 brand. The copper electrode provides fine-droplet transfer of metal to the seam.

Both types have steel wire at their core. An appropriate coating has been applied to it. To carry out welding with these samples, a standard welding machine is used.

Electrodes for cold welding of cast iron

Cold welding technology refers to a process that takes place at a temperature of about 200 °C. For such low temperatures, the following brands are used: OZCh (2 or 6), MNCh-2 or the so-called universal ones, which include TsCh-4. Welding cast iron with electrodes using the cold method is carried out with lower or vertical arrangement of parts.

Each of the listed types performs well under appropriate conditions. Electrodes for cold welding and surfacing of the OZCh-6 brand have proven themselves well. The task of high-quality welding of important joints and surfacing without heating is carried out with products of the MNCh-2 brand. Under certain conditions, the OZZHN-1 grade is used for surfacing without heating.

They allow you to deposit large volumes of metal.

Electrodes for welding cast iron and steel

The task of welding metals such as cast iron and steel often arises. In this case, they try to select the most suitable products for steel. These include universal grades TsCh-4. They have proven themselves in hot and cold welding of these two metals. In addition to domestic samples, imported products of the Ficast NiFe and ZELLER 855 brands have proven themselves well. They have shown good results and provide an even and durable seam.

Ductile iron electrodes

To obtain the strongest and most reliable seam when working with forged cast iron, welding electrodes of the following brands are used: MNCh-2, OZCh-6 (2) or TsCh-4.

Electrodes for gray cast iron

The best results for connecting parts made of gray cast iron, eliminating cracks and defects, are obtained when using cast iron electrodes of the following brands: OZCh-6 (2), OZZHN-1 or 2.

Popular manufacturers

The most famous manufacturers that have established themselves as manufacturers of the highest quality and reliable products are:

• domestic ones are ASPIK; SpecialElectrode; Frunze-Electrode;

Source: https://stankiexpert.ru/spravochnik/svarka/ehlektrody-dlya-svarki-chuguna.html