How to weld metal to cast iron

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:

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.
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.
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.
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

g84jsm9tB4S

Carrying out construction work or various restoration operations often involves the need to weld various metals. A typical example is steel and cast iron.

In fact, these metals are close to each other in chemical composition, the main difference being the percentage of carbon. This moment complicates the work.

The second nuance is that carbon inclusions in the structure can be represented by granules of various sizes. If they are small, then the process does not cause any particular difficulties, but in a situation where the granules are large it is very difficult, even if visually the seam seems uniform, correct and reliable, great strength cannot be achieved.

So, let’s figure out how to weld cast iron with steel using electric welding, what technological requirements must be observed, and whether there are any effective alternatives for the connection.

Basic techniques

There are several of the most effective technologies:

Hot method . Before starting work, both parts are heated to 600 degrees. Local heating using a blowtorch is allowed. You can determine whether the desired temperature has been achieved by the fact that the cast iron turns crimson in color. Quite long, heavy, but the most reliable method in terms of strength.
Semi-hot technology is based on heating up to 200-300 degrees. The optimal choice for high alloy alloys.
The cold method does not involve preheating. It is simple to implement, but can be used exclusively when forming a weld, that is, a weld that functions in compression.

Welding cast iron with steel is complicated by the structural features of the first material. The top layer is not very dense, and therefore the part needs preliminary preparation. It is not just degreased, but cleaned until a clean layer appears.

If this requirement is ignored, the finished seam will be loose, porous and fragile.

Selecting Electrodes

Practice shows that better results can be achieved using the following elements:

TsCh-4 . Electrodes of this type are suitable for welding using both cold and hot methods. The scope of application is not limited to this; it is allowed to use products for surfacing, soldering, and eliminating defects in surfaces made by injection molding.

A mandatory requirement is that welding must be carried out in the lower position with direct current with reverse polarity.

OZCH-2 . The mandatory requirement for the welding process is similar to the previous versions. Experienced welders recommend using these elements when working with parts with thin walls, since burning metal to a significant depth is excluded.
MNC-2 . Efficient but specialized electrodes. A decent result can only be obtained if the work is carried out using the hot method.

If we talk about imported analogues, the best electrodes for welding are Ficast NiFe models , which allow you to form joints that can withstand bending and torsion loads, and Zeller under the indexes 866 and 855 .

The second option is universal and allows you to work without preheating the metal.

Working instructions

Let's move on directly to how to weld cast iron to metal:

1. The necessary parameters of the electric current are set. Operation is carried out at direct current with reverse polarity - this is the case if the open circuit voltage does not exceed 54 V. If the open circuit voltage is above 54 volts, then the connection is made with alternating current.

The work is being carried out gradually, in small sections. The maximum permissible roller length is 30 millimeters. First, the cast iron part is processed, and the steel product is attached to it.

2. If a seam of large thickness is formed, then it is welded gradually, and it is necessary to forge it before making subsequent layers. Forging is carried out using a hammer, the fresh seam is compacted until it begins to emit a characteristic ringing sound.

The direction of the seams is different, that is, the second one is made perpendicular to the first. This allows you to achieve sufficient strength characteristics.

3. If welding with an electrode is carried out using a hot or semi-hot method, then sufficient cooling of the surfacing zone should be ensured. The seam is heated periodically to prevent its rapid cooling.

A sharp drop in temperature will cause thermal stresses to arise inside it, which can provoke both deformation and destruction.

Source: https://pechi-sibiri.ru/kak-privarit-metall-k-chugunu/

Welding cast iron with steel

Cast iron and steel are very similar metals, the only thing that differentiates them is their carbon content. There is more of it in cast iron. And it is this chemical element that complicates the process of welding cast iron. But the most important thing is that the carbon in its composition can be small granules or large ones.

So the first option can still be welded, but the second is almost impossible. Even with a seemingly well-carried-out welding operation, the result will still be poor.

And when we talk about such a technological process as welding cast iron with steel, it is necessary to understand that similar metals are still dissimilar. And this is the whole difficulty.

Steel can be welded to cast iron by electric arc welding using various electrodes. For example, domestic brands TsCh-4, OZCH-2 or OZL-25. Completely different electrodes, so they are used if the welding seam will be processed in the future or not.

If welding is carried out with further processing, then the OZL-25 or OZCh-2 electrode is used, in another case TsCh-4. The first electrode forms a homogeneous type of metal with high permeability and heterogeneity in the weld seam.

The latter value makes it possible for the metal not to burst during processing, because it relieves the stress inside the weld.

Consumable electrode welding technology for steel and cast iron

As with all welding processes, the first step is to prepare the two metals. They must be cleaned to a metallic shine in the welding zone. Since cast iron is a porous metal, oils and fats easily penetrate deeply into its body. So, it is imperative to clean areas with oil stains until they are completely removed.

As for the welding mode of cast iron and steel, everything will depend on the welding equipment.

If the no-load voltage of the welding machine does not exceed 54 volts, which is a standard value for many types of welding equipment, then the welding process is carried out by direct current of reverse polarity.
If the open circuit voltage is above 54 volts, then alternating current is used for welding.

In both cases, it is necessary to heat both workpieces to a temperature of +600C. This is done with one sole purpose - to prevent large expansion of the workpieces in the welding zone. After all, there is also a reverse process.

That is, the greater the expansion, the greater the contraction when metals are cooled. This can lead to cracking of the weld. If you take into account all the above recommendations, the end result will be a high-quality seam.

Moreover, it can be obtained in just one pass with the electrode.

If the composition of steel and cast iron contains alloyed additives, or the workpieces themselves are thick-walled parts, then it will be necessary to cook cast iron with steel using a different technology.

Firstly, no preheating is used.
Secondly, two metals must be welded to each other using small beads no longer than 2.5 mm.
Thirdly, the next roll is formed only after the previous one is well cooled.

It is the last two positions that will affect the tightness of the seam. That is, when welding steel and cast iron using this technology, there is no need to talk about the tightness of the seam. Because the subsequent roller is superimposed on the cooled previous one. In addition, the weld itself will have increased fragility.

Argon arc welding

In principle, what was said above fully applies to argon arc welding with a non-consumable electrode in a shielding gas environment. The only thing added to welding technology is additive and gas. Everything is clear with gas, because it is the same for all types of welding, regardless of the type and type of workpieces being joined, or rather, their metals.

THIS IS INTERESTING: How much does the reinforcement weigh 14

But the filler material is selected according to the properties of the base metal being welded. And since there are two of them, you will have to take into account the welding abilities of each of the two. And since cast iron is, so to speak, weak, then the additive should be selected according to it. So, as a filler material, you can use welding flux-cored wire, from which the coating is beaten off. Some craftsmen use strips of cast iron, cut into small pieces.

True, both materials can be used only if the welder has enough experience in using this technology. The thing is that an incorrectly set mode and an incorrect melting speed of the additive can lead to the formation of so-called intermetallic structures in the weld pool. They have increased fragility. This is why practical experience is considered an important component of the quality of the final result when welding steel and cast iron with a non-consumable tungsten electrode.

Therefore, some purely practical advice.

To weld two metals, it is best to use nickel-based additives, which were specifically invented for welding cast iron products. But if the requirements for the strength and reliability of the joint are quite large, then even such an additive will not be able to fulfill them.
You cannot cook cast iron with steel with a wide bath and large heat inputs.
It is recommended to deposit a nickel additive on the cast iron edge before starting welding work. That is, to form the so-called transition layer.
You can weld cast iron to steel without preheating or with it. The first option is chosen only if during operation of the welded part it will not be subjected to great heat, no more than +300C. If there are no such requirements, then heating will have to be done. Small workpieces are heated completely, large ones only in the welding zone.
Cast iron is a metal with low ductility and very low linear expansion compared to steel. Therefore, it is very important to reduce shrinkage stresses in the weld. Cast iron shrinks a little, steel, on the contrary, shrinks a lot.

What can you do about the last position? The greatest effect can be achieved by hitting the weld with a hammer. This process is called forging. For this, a hammer with a rounded head is used. The metal must be beaten to such an extent that a ringing sound is produced.

There is another option to increase the effect. To do this, you will have to weld with a large diameter filler wire. The seam itself must be done using rollers 4-5 cm long each. In this case, the electric arc should be directed towards the previous roller. It is necessary to cook evenly along the joint without oscillatory movements.

Electrodes

Electrodes have already been discussed above, but it is necessary to identify some serious positions on which the quality of the final result depends.

TsCh-4 can be used for both cold and hot welding of cast iron and steel. They are also used to perform surfacing, soldering and repair of casting defects. In addition to steel and cast iron, this brand of electrode can also weld workpieces made of high-strength malleable cast iron. Cooking with such electrodes can only be done in the lower position using direct current of reverse polarity.
OZCH-2 is used in exactly the same positions as the previous consumable. But experts recommend welding thin-walled workpieces with it. In addition to the lower position, the electrode also cooks well in the vertical position.

By the way, welding of two metals (cast iron and steel) is considered to be of higher quality when manual electric welding is used. But, as mentioned above, if the process is carried out with preheating. Cooling of welded steel and cast iron parts must be carried out slowly. Therefore, after completing the work, the welded structure must be covered with dense material. It’s better to put it in an oven, where the parts were heated before welding, and cool the assembled part along with it.

These are the technologies used today to connect steel and cast iron workpieces. As practice has shown, they all cope well with this, the main thing is to choose the right consumables and welding modes.

Source: https://svarkalegko.com/tehonology/kak-privarit-chugun-k-stali.html

How to weld cast iron to metal

I have to repair the UAZ gearbox and, in the future, the tractor engine block. In connection with this, the question is: what are the features of welding cast iron?

Example of a weld in cast iron

The alloy you specified is a rather difficult material, because...
contains from 2.14 to 6% carbon (everything below 2.14% is called steel). High carbon content negatively affects its weldability. As a melting method, manual arc (MMA) or semi-automatic welding (MIG-MAG) is best suited. When choosing an inverter, consult with store specialists, they will help you choose the right option.

Now, actually, about the features of cast iron:

• it has high thermal conductivity - accordingly, it very quickly releases the heat transferred to it. Rapid cooling leads to the appearance of hardening areas in the weld area and the formation of white cast iron prone to embrittlement.

• Lack of plasticity creates internal supertension in the structure • Carbon burns intensely when heated and melted, releasing carbon monoxide, which promotes the development of pores and cavities.

• Cast iron oxide is very refractory

Electrodes for cast iron

For RDS (MMA) the following are used:

• cast iron is now rare. They can be very large in diameter from 6 to 15 mm. It is recommended to use electrodes with a minimum diameter and at low currents.• copper based,• nickel based

• steel.

Application of steel electrodes

For cast iron, you can't imagine anything worse. It is advisable if minor defects are being repaired and no further machining is planned. The bleaching process causes the seam to become pliable and brittle. TsCh-4 electrodes are used, the rod of which is made of pure Fe or UONII-13/45, which are used for welding “black” and low-alloy steels

The best characteristics are shown by nickel-based electrodes (ESAB electrodes OK 92.18, OK 92.58). They carry out cold welding of cast iron (see below), but slight heating to 40 degrees is recommended. The resulting seam has good strength characteristics and can be processed with a cutter or milling cutter without restrictions.

Cast iron is welded well with copper-based electrodes, but you will not get the strength properties of the weld and heat-affected zone, this is due to the fact that Cu and Fe do not interact with each other until the Cu dissolves.

For semi-automatic welding

steel, nickel and silicon-bronze wires are used in combination with shielding gas or its mixtures.

Distinguish between hot and cold welding

• During hot welding, cast iron is heated to a temperature of 250 to 650 degrees, followed by melting at low currents. Overheating and high currents can lead to cracking. After the welding operation, the cast iron is slowly cooled. To do this, it can be placed in sand or covered with thermal insulation material.

• Cold welding for cast iron is carried out without heating, but you need to make the seams as short as possible, it is necessary that they cool gradually.

Read Repair of cast iron products by welding. From the experience of Uralmashplant.

Makita anti-splash sander

The welder may encounter “plenty” of spatter. In this case, stripping to a depth of more than 0.5 mm should help.

The fact is that in the manufacture of the sand-clay mold into which cast iron is cast, not only sand and clay are used, but also binding components, including rosin.

When heated, these impurities may enter the surface layer, and they “gas” when heated. Use a Makita sander with a sanding or roughing wheel to remove the surface layer.

Welding cast iron and steel

Hello, I am making a fence with a foundation in the form of a strip. Every 2.5 meters there are metal gratings that will be between the stone pillars. Cast iron sewer pipes were found to reinforce the stone columns. The grids in the posts will be secured with steel strips. Question: how to weld steel to cast iron?

Typically, before welding, steel and cast iron workpieces are heated to a temperature of 600 degrees. Preheating allows you to obtain continuous, hermetically sealed welded joints in one pass. But if, as in your case, preheating in a furnace is not possible, then the technology is changing. Weld the fence using rollers no longer than 25 mm.

Before surfacing a new bead, you must wait until the previous bead has cooled completely. That is, the base metal of the connection cannot be overheated. Also, the weld obtained in this way cannot be subjected to mechanical processing, since it has increased fragility. But there should be enough strength to maintain the integrity of a structure such as a fence.

To obtain a less brittle welded joint and a more durable seam, use electrodes for welding cast iron - as well as cast iron and steel - ESAB OK 92.58.

Source: https://steelfactoryrus.com/kak-privarit-chugun-k-metallu/

How to weld cast iron to metal? — Metals, equipment, instructions

page » About welding » How to cook correctly » How to cook cast iron » Welding cast iron with an electrode at home

Cast iron is an alloy of carbon and iron, which also contains alloying additives and impurities. Cast iron parts are widely used not only in industrial and production areas, but also in everyday life. Cast iron products for private use: plumbing elements, fence structures, car parts and much more. The active use of this alloy leads to the need for welding work.

The main difficulties in welding cast iron that home craftsmen encounter:

due to the fluidity of the alloy, it is recommended to carry out welding in the lower spatial position;
non-compliance with temperature conditions leads to overheating of cast iron, which can cause the formation of pores and stress in welds;
cast iron in a molten state can release gases , which will negatively affect the quality of the connection;
Accelerated or uneven heating or cooling can promote cracking .

In order to obtain a high-quality connection of cast iron products at home, it is necessary to take into account these specific characteristics, as well as correctly prepare the working surface, select the correct welding mode and electrode.

Preparation for welding

Preparatory operations must be carried out carefully and carefully, as this is one of the fundamental principles of obtaining a high-quality connection:

the structure is cleaned of dirt, debris and dust;
then you should degrease the parts with a solvent, for example, acetone;
when working with thin cast iron, you need to use pads to remove heat ;
edge cutting should be done before welding thick-walled products; for this, a file or grinder is used;
cracks must be drilled along the edges and cut to their entire length; an alternative method is to cut out the cracks and round off ;
depending on the chosen welding method (hot or cold), the product is heated or not. heated using various equipment: ovens, gas burners, or using improvised means: a blowtorch.

Welding methods

Experts distinguish 3 methods of welding cast iron:

Hot is carried out by heating the cast iron parts before making the connection, the temperature is 600-650°C. This method cannot be used at home.
Semi-hot is practically no different from the previous method, the difference is only in the heating temperature, the product is heated to 300-350°C.
Cold implies the absence of heating of work products. Welding cast iron with an electrode at home is carried out using this technology.

Welding cast iron using an inverter and a consumable electrode is most often carried out using the cold method. Important components of successful work are: the correct choice of electrode and optimal welding modes.

Electrodes OZCH-3

The performer must make the connection with special electrodes containing nickel and/or copper:

OZZHN-1;
OZCh-2;
OZCh-3;
OZCh-4;
OZCh-6;
MNC-2;
TsCh-4.

Recommended welding modes for some of the listed brands:

Electrode brand	Current strength for an electrode with a diameter of 3 mm.	Current strength for an electrode with a diameter of 4 mm.	Current strength for an electrode with a diameter of 5 mm.	Current strength for an electrode with a diameter of 6 mm.
TsCh-4	65-80	90-120	130-150	—
OZCH-2	90-110	120-140	160-190	220-250
OZZHN-1	100-120	130-150	160-180	—
MNC-2	90-110	120-140	160-190	210-230

The following technological features should also be highlighted:

the length of one continuous seam should not be 30-50 mm;
frequent breaks in the welding process will help eliminate the possibility of overheating; temperatures above 80°C are unacceptable;
polarity is reversed.

This welding method can be performed in two ways: using studs and in layers.

1. The studs are equipped with threads, which allows them to be screwed into the edges of the product being welded. The studs should be staggered/staggered to prevent overheating during welding. The dimensions of the studs depend on the thickness of the workpiece; when selecting them, you should rely on the following recommendations:

diameter - 0.3-0.4 product thickness, but not more than 12 mm;
screwing depth - 1.5 times the diameter of the stud, but not more than half the thickness of the product;
the height of the protruding part of the pin is 0.75-1.2 times the diameter.

After installing the studs, you can start welding. Metal is deposited around each pin, layer by layer. Then the performer needs to weld the space between the studs, which remains untouched, and make one or more connecting seams.

2. Multi-layer welding is performed after cutting the edges. The presence of sharp corners is not allowed. Surfacing should be done from the edges. The first layer is the main one, so during its deposition you need to carefully monitor the welding mode. Each subsequent layer, except the first and facing ones, must be forged with a hammer, without cooling.

The following video demonstrates the Zeller 855 cast iron electrode, but from the video you can see how welding is done.

This information will help the contractor learn how to cook cast iron with an inverter using electrodes on cast iron, and easily carry out the connection work.

Welding with conventional electrodes

In order to save money, you can use ordinary (steel) consumables instead of special ones. General purpose electrodes have a more affordable price.

The technology of multilayer welding with conventional rods is practically no different from the method discussed above, which uses special rods coated with non-ferrous metals. The stages of work are similar.

The only difference is that the layers following the first are deposited not with a special electrode, but with a regular one.

Attention! Welding cast iron with electrodes not intended for this purpose is possible, but we do not recommend using it in any critical connections! This information is provided only for welding for experimental purposes.

This welding method can be carried out using a cold or semi-hot method. A little preheating will improve the structure of the weld metal.

Cast iron electrodes are cast rods coated with coating, used to correct defects in cast iron. This type of consumables includes the following brands: MNCh-1; OZCh-1; OZB-2M.

THIS IS INTERESTING: What types of alloys are there?

Welding is carried out using direct and alternating current. The current value is determined as follows: 50-60 A per 1 mm. electrode rod.

Welding cast iron using this technology is carried out in a protective environment of argon or fluxes, the main component of which is borax. Cast iron or special rods containing nickel, aluminum and copper are used as filler materials. Welding cast iron is carried out using tungsten, carbon and graphite electrodes.

The most common method is argon arc welding (AC TIG). In order for the work to be successful, you should adhere to several rules:

Thorough cleaning of the surface from debris and dirt;
the workpiece must be fixed at several points;
It is recommended to use slight preheating of the product; for this you can use improvised means. It should be remembered that the presence or absence of heating depends on the type of cast iron being welded;
the additive is supplied at an angle of 20-30 degrees;
it is necessary to use small amounts of current;
the connection should be carried out in stages : the performer welds a small section of 2-3 cm and forges the deposited metal so that
avoid residual stress. Forging is done with a small hammer, the weight of which does not exceed 1.2 kg, the hammer is of a rounded type.
Cooling of the part after welding is carried out gradually .

This method is not the main one when connecting cast iron products. This is due to certain difficulties that arise during the work process, as well as an increased level of labor and financial costs.

DIY electrodes for cast iron

In the absence of special electrodes for welding cast iron, you can independently make consumables that are similar in characteristics to the OZCH-2 and OZCH-6 grades. Next, we will look at two ways to make electrodes for cast iron with your own hands.

The production of electrodes for cast iron is carried out using the following technology:

Warning!

Source: https://spb-metalloobrabotka.com/kak-privarit-chugun-k-metallu/

How to weld cast iron to metal with a simple electrode?

Durable and reliable - cast iron is one of the most common materials used in everyday life and industry.

It has its undeniable advantages: it lasts a long time, is relatively inexpensive, can be easily welded, and does not lose its performance characteristics over time.

When might it be necessary to weld cast iron with an electrode? If, for example, a seam in a heating radiator is leaking, it needs to be patched, or several more compartments need to be welded to the batteries.

Cast iron: types, application

Cast iron is a kind of mixture of iron and carbon. The material is hard and wear-resistant, but, paradoxically, quite fragile if not handled correctly. This is why welding cast iron with an electrode at home using an inverter should only be done after careful preparation (this will be discussed below).

Cast iron has been known in the world for a long time - it is believed that it appeared in the 6th century BC.

The average melting point is over 1000 degrees Celsius. You can work with the material when heated to 600 degrees.

By type, cast iron metal is divided into the following categories:

white;
half-hearted;
grey;
high strength;
malleable.

Over time, cast iron does not lose its relevance; it is used in various spheres of human activity. The material is used for the following purposes and tasks:

forging fences;
production of machine tools;
production of frying pans for household use;
manufacturing of heating radiators, pipes, plumbing connections;
creating baths;
in the automotive industry - for the production of crankshafts, cylinders, engines and other things.

This is only a small part of the tasks that ordinary cast iron can successfully cope with. An important feature is that surfacing cast iron with electrodes can be done at home without the help of a professional welder.

Types of welding

To know how to weld cast iron with a conventional electrode, it is important to understand the types of welding in general. They are divided into:

hot;
semi-hot;
cold.

Hot is indeed such, occurring at temperatures between 600 and 700 degrees Celsius. The metal is heated in industrial furnaces, which are considered heavy-duty equipment. Cast iron becomes flexible, like plasticine, and is easy to work with. During the process, no cracks or pores appear on the product that would interfere with normal operation in the future.

Experts call this welding method the most ideal for cast iron. Naturally, to the question: is it possible to cook cast iron using conventional electrodes at home using the hot welding method, the answer will be negative. Creating such a colossal temperature in an apartment or garage, for example, is dangerous to life and health.

Semi-hot welding is also impossible at home. It is carried out at a temperature of 300-400 degrees Celsius. For heating, special hair dryers or heating elements are used. This method is used in industry.

Its main advantage is faster cooling compared to the hot method.
For a novice master, the semi-hot technology of welding cast iron with electrodes is practically impossible. Cold welding is suitable for home use.

It occurs at a maximum temperature of 80 degrees Celsius.

Preparation for welding with electrodes

To begin the welding process, it is necessary to make thorough preparations for it. In particular:

sand the surface;
degrease parts of the unit without fail;
prepare the welding machine, make sure that it is technically sound;
decide how exactly the welding will take place: on studs or in multilayers;
prepare a sufficient number of electrodes;
remember the safety rules.

It is forbidden to start work if the surface is not cleaned and sanded - this creates the possibility of a dangerous situation: a sharp element will jump off during the welding process and cause injury to the worker. Simple electrodes will not work in this case. It is necessary to purchase those that contain chromium, copper and nickel.

You cannot start work without theoretical preparation for the process. Failure to comply with the technology will lead to the fact that when the material hardens, numerous pores and cracks will form, cast iron will lose its excellent performance properties, and it will simply be impractical to use it in the future.

Features of the welding process

Now we’ll tell you how to weld cast iron using electric welding. When the master is convinced of the reliability of the equipment, he can begin the process. To do this, you need to choose how to cook cast iron with simple electrodes:

on studs;
multi-layered.

In the first case, the master first installs the pins themselves, and forms a seam around them. Experienced welders recommend performing the procedure in a staggered manner to prevent overheating of the material. The work is completed with a connecting seam - it goes from one pin and its “surroundings” to the other.

The multilayer method is as follows: chamfers are created, then the initial layer is fused, it is hammered, then a second layer is laid, tapped again, and so on.

After the seam has cooled, it must be sanded to give the product an aesthetic appearance.

If it is possible to access the inside of the product, then the initial layer in the multilayer method is placed on the outside and inside. This makes the connection even stronger.

In general, there is nothing complicated about how to properly cook cast iron with electrodes. The main thing is to follow safety rules.

Safety precautions

Even before cooking cast iron with a conventional electrode, it is important to take care of following safety precautions:

Place a fire extinguisher near your workplace;
make sure the welding machine is in good working order;
put on special protective gloves for welding activities;
cover your face with a mask or at least glasses;
work exclusively in thick clothing so that particles of hot metal do not have the opportunity to come into contact with the skin;
it is important that fresh air always flows into the room where welding is performed;
if you are welding for the first time, it is wise to invite an assistant or at least an outside observer, so that in case of an emergency, there will be someone to help.

Naturally, it is advisable to work during daylight hours or at least in sufficient lighting, in an absolutely sober and healthy state.

Conclusion

In general, the process of how to weld cast iron with metal with an electrode is described above. Experienced welders will tell you the details and subtleties. Don't hesitate to ask them for advice. When working at home, choose the cold method. Work only with proven equipment, do not forget about safety precautions.

Interesting video

Source: https://varimtutru.com/kak-privarit-chugun-k-metallu-prostym-elektrodom/

How to cook cast iron with metal

When carrying out repair work, situations arise when it is necessary to connect dissimilar metals. Is it possible to weld cast iron and steel? Yes, but this can be done by people with experience.

Cast iron alloys are characterized by a high carbon content; when it burns out, the structure of the metal changes. The joint is boiled at low temperature, up to 120°C. Steel, on the contrary, needs to be very hot.

A buffer layer technology has been developed to connect cast iron parts with other ferrous alloys. Nickel alloy provides a strong connection between dissimilar metals.

Technology of welding cast iron with steel using a consumable electrode

There are several methods of welding cast iron; they are used to join cast iron alloys with other metals:

Hot - before joining the parts, the ovens are preheated to 600°C completely. Heating with a blowtorch is allowed only in the work area (cast iron becomes crimson in color). Used for reliable connections.
Semi-hot, good for alloys. The parts to be joined are partially or completely heated to 200–300°C.
Cold - parts are connected without heating, used for overlays - seams working under compression.

Joining metals by manual electric welding involves preliminary preparation of surfaces. Cast iron alloy is porous and absorbs oil well. It is not enough to degrease the stain; it must be cleaned to a clean layer, otherwise the seam will turn out loose.

How to weld steel to cast iron:

First you need to select the current parameters. If the welding machine only works on constant, switch the Polarity to reverse. It is necessary to take into account the no-load indicator (voltage between the poles without an arc), the permissible value is up to 54 V. Operating on alternating current is allowed only with no-load from 54 V.
Welding is carried out in small sections, the beads are made no more than 3 cm long. First, cast iron is deposited, then a steel part is welded to the buffer layer.
Thick-walled seams are welded in multi-layers, each one is hammered before applying the next. It is made perpendicular to the first - this is how the strength of the connection is achieved.
After joining the cast iron alloy with steel using hot and semi-hot methods, it is important to observe the cooling regime of the surfacing zone. The seam is periodically heated so that it cools gradually. When suddenly cooled, the cast iron alloy cracks due to internal stresses.

Applications of argon arc welding

The use of refractory electrodes and copper-nickel filler wire gives good results.

How to weld steel to cast iron (several recommendations):

The additive is selected according to the type of metal and type of cast iron. Nickel-based flux-cored wire is most often chosen; the coating is first removed from it.
Argon is used as a protective atmosphere; it saves the seam from oxidation.
Refractory tungsten electrodes are chosen for work.
To work with thin-walled elements, experienced welders use small thin pieces of cast iron instead of wire.
For connections that experience only static loads (compression), nickel alloys can be used. They adhere perfectly to any grade of steel.

Welding cast iron requires a different technological approach. This is due to the chemical characteristics of the metal, which affects its processing and, in particular, welding.

In this article we will look at technologies for welding cast iron at home using two main techniques.

Features of the material

Cast iron in its composition is a combination of iron elements and a certain amount of carbon. But, in comparison with steel, the latter contains over 2.14%.

Depending on the composition, cast iron can be white or gray.

White cast iron is essentially a semi-finished product and is used to produce malleable metal. It is very fragile and products are not made from it.

The gray appearance of this metal is most often used in industry and the manufacture of various things.

There are also malleable and high-strength cast irons.

What are the features of this material in welding work? The main thing is the difficulties in obtaining a high-quality seam, associated with the following problems.

Cast iron, due to its heterogeneous structure, is prone to cracking at the welding site. This is due to its exposure to high arc temperatures, which leads to its bleaching and a change in composition at the cooking site (high temperature plus rapid cooling).
Due to the high-temperature influence of the electric arc, part of the carbon in the metal composition burns out, and as a result, pores form in the weld. This does not add strength to such a connection and the quality deteriorates significantly.
When melted, cast iron is very fluid, which does not allow the formation of a correct seam. The higher the percentage of carbon, the higher the fluidity will be.
Also, during welding, oxides can form in the weld, which also do not strengthen the joint. In addition, oxides are more refractory.

Source: https://MyTooling.ru/instrumenty/kak-varit-chugun-s-metallom

How to weld metal to cast iron - Metalworker's Guide

Cast iron is one of the most popular metals for making a variety of products: from car parts to water pipes.

At its core, cast iron is carbon and iron, which in the right proportions form a very strong and durable metal.

Cast iron parts can be found in factories and industries, and even old cast iron frying pans have served their owners for decades.

Despite many alternatives, cast iron is not slowing down and remains a very popular material.

Therefore, a home or professional welder will sooner or later have to face the need to weld cast iron.

In this article we will tell you in detail what features this metal has, how to weld cast iron correctly and how to carry out welding work on cast iron with maximum benefit.

Features of cast iron

Welding cast iron in a garage or in large-scale production has a number of nuances that need to be taken into account before starting work. There are not many of them, so we will tell you about them all.

Welding cast iron must be done in the lower position, since the metal is very fluid. Do not overheat cast iron when welding, otherwise pores are guaranteed to form, followed by cracks.

THIS IS INTERESTING: Magnetic corners for welding

Also, when melting, cast iron releases a special gas, which negatively affects the formation of the weld. Therefore, welding of cast iron parts must be carried out quickly and in compliance with the temperature regime.

Do not overcool hot cast iron, otherwise cracks will form again.

In order to get a truly high-quality welded joint when working with this metal, take into account all the features and characteristics of the cast iron itself.

Be sure to prepare the metal before welding, select the correct operating mode in your welding machine and use special electrodes.

But we will talk about all this further; first, we will deal with the preparation of the metal, since this is where the technology of welding cast iron begins.

Preparatory stage

The preparatory stage is one of the most important, since the quality of further work depends on proper preparation. First, clean the surface of dirt, dust and corrosion (if any). Degrease the metal with acetone.

If you are welding thin cast iron, make sure you have a heat-dissipating pad in advance. Cut the edges using a file or grinder.

If you have to weld cast iron parts using the hot method (a method in which the part is heated before welding), then use a stove or gas burner for this.

Inverter welding with consumable electrode

Now let's move on to welding methods. Cast iron is cooked at an average temperature, so it can be welded with an inverter machine right in the garage or at the dacha, not to mention the factory workshop.

Welding cast iron with an inverter is carried out using a consumable electrode, as well as with a welding machine and a cold method (a method in which the part is not heated in a furnace or manually using a torch before welding).

Consumable electrodes must contain nickel or copper. Below you can see a table with recommended settings for different electrodes.

It is allowed to make intermittent seams, but not shorter than 3 centimeters in length, you need to use a temperature of no more than 80 degrees Celsius and allow the cast iron to cool. Also set the polarity to reverse.

Welding with steel electrodes

Is it possible to weld cast iron with ordinary steel electrodes? You can of course try, but we don't recommend doing it, especially with arc welding.

Yes, standard steel electrodes are cheap, but such a connection will be unaesthetic and short-lived.

If you need to weld a critical part (for example, part of a water pipe), then it is better to use special electrodes and do not skimp.

Welding with cast iron electrodes

For cast iron, specialized cast iron electrodes are best suited. You can cook it either cold or hot, as you see fit. We often warm up the part before welding so that the metal structure becomes better and the seam is more reliable.

Using such electrodes, you can easily correct multiple defects in cast iron, such as cracks, holes or chips. Electrodes of the MNCh-1, OZCh-1 or OZB-2M brands are often used in work. They are not that expensive, but the quality of work is excellent.

Welding cast iron with an electrode at home is carried out using direct and alternating current. To correctly set the current value, look at how long your electrode is. 1 millimeter of electrode corresponds to 50 amperes.

Welding with non-consumable electrodes

Welding of cast iron parts with non-consumable electrodes is carried out in a shielding gas environment or using drill fluxes. Nickel, copper or aluminum filler wire can also be used. Carbon, tungsten or graphite rods are used as a non-consumable electrode.

In most cases, when using non-consumable electrodes, cast iron is welded with argon (so-called TIG welding). We recommend slightly heating the part before welding using a gas torch.

Set the welding current to a small value. Welding should be intermittent, 3 centimeters at a time.

After welding, you need to gradually cool the part and monitor the temperature to prevent overcooling and the formation of cracks.

Welding cast iron with argon is rarely used, since it requires not only an electrode, but also a gas cylinder, preheating of the part and careful cooling, and all this takes a lot of time. Also, semi-automatic welding of cast iron is more expensive than other methods, but when you have no other option, you can weld using this method.

Gas welding of cast iron

Gas welding of cast iron is a fairly popular method, since the work requires only flammable gas, oxygen, cast iron welding wire and flux. At the same time, the quality of the seams is very decent.

Welding wire for cast iron used in the work must contain flint. This is very important because silicon promotes the formation of graphite in cast iron and does not bleach the metal.

The use of fluxes when gas welding cast iron is simply necessary, especially if you are welding steel with cast iron. Cast iron and steel are generally very different metals, so an oxide film forms on the surface in large quantities.

Instead of a conclusion

Welding cast iron with an electrode at home requires the master to follow the technology and take into account all the nuances of the metal itself.

Take your time while working, use quality components and practice as much as possible. This way you can gain experience.

Leave your comments and share this article on social networks. Good luck!

Source: https://ssk2121.com/kak-privarit-metall-k-chugunu/

How to weld steel and cast iron - Do it yourself

Carrying out construction work or various restoration operations often involves the need to weld various metals. A typical example is steel and cast iron.

In fact, these metals are close to each other in chemical composition, the main difference being the percentage of carbon. This moment complicates the work.

The second nuance is that carbon inclusions in the structure can be represented by granules of various sizes. If they are small, then the process does not cause any particular difficulties, but in a situation where the granules are large it is very difficult, even if visually the seam seems uniform, correct and reliable, great strength cannot be achieved.

So, let’s figure out how to weld cast iron with steel using electric welding, what technological requirements must be observed, and whether there are any effective alternatives for the connection.

Argon arc technology

The connection of these types of iron is also possible using the argon arc method. To achieve a high-quality result, you must adhere to a certain set of recommendations:

The choice of additive is an important point. The exact grade of additive depends on what type of cast iron is involved in the process. The most widely used is nickel-based flux-cored wire, from which the coating has been previously removed.
Argon is a gas that forms a protective atmosphere that prevents oxidation of the weld.
The best working elements are electrodes made of tungsten, a refractory metal.
If the surfaces to be welded are of small thickness, then an alternative to nickel is thin cast iron plates.
If the weld will be subjected exclusively to static loads (compression), then a nickel alloy is the best option. This metal adheres well to all types of steel, regardless of grade.

on the topic, argon arc welding of cast iron:

Let's sum it up

Connecting cast iron and steel elements is a completely feasible task. The main thing is to adhere to the above tips and recommendations.

An important point is that with an increase in the degree of alloying of steel, the friability of the weld also increases. To achieve the required strength, careful forging and compaction are required.

(15,00 out of 5)

Source: https://vsesamado.ru/kak-svarit-stal-i-chugun.html

Features of welding cast iron, types of cast iron

Experienced welders can determine the weldability of cast iron from just a
cut. It is believed that if the structure of the metal is finely dispersed and close to gray in color, then such cast iron can be welded much easier than coarse-grained metal of dark shades.

If we are talking about welding parts that were in an oil environment or were subject to regular oxidation in an aqueous environment, soil or other similar conditions, then such a welding material will not be suitable.

Since cast iron is a metal with limited weldability, it is worth taking into account the following features:

The metal is fluid, so the main and only correct welding position is the bottom one.
If you do not observe temperature conditions and chop the metal, then when the carbon burns out, pores will form.
Low ductility and non-compliance with temperature conditions are the main causes of stress at welded joints.
Molten iron can create oxides that will have a higher melting point than the parent metal.

The problem you may encounter is the formation of cracks at the welding points when the part cools.

This can only be solved if we fully adhere to the technology, in our case - cold welding.

We recommend! Essence and modes of gas acetylene welding

Cast iron welding methods

There are three ways to weld cast iron:

Hot welding. The main and most correct method. It consists in the fact that before working with the electrode, the workpiece is heated to 600 - 650 degrees. This allows you to avoid the formation of compounds with a high melting point, overheating and tension of the metal at the joint. Heating is carried out in ovens, gas or other burners. For home conditions, this method is a stretch, because in addition to the heating device, you need to know at what moments you can work at the welded joint, how to cool the metal and many other nuances.
Semi-hot welding. It is practically no different from the previous method, with the exception of the heating temperature. Here the product is heated to 300 - 350 degrees.
Cold welding. The method does not involve heating the workpiece, but it is based on many other technological aspects, failure to comply with which will lead to the impossibility of making a high-quality seam. Welding cast iron at home with an electrode is carried out in this way.

Preparing cast iron for cold welding with an inverter

Before welding cast iron, it must be prepared. First, the desired area is cleaned with a grinder with a flap wheel or other suitable attachment. After stripping the top layer to non-oxidized metal, it is necessary to carry out mandatory degreasing with gasoline or any other solvent. If you decide to repair the crack, then you need to clear the metal until it ends, and drill a hole with a diameter of 10 mm in this place.

Cutting a crack when welding cast iron

It is worth talking separately about the following preparation features:

1. Hairpins. Arc welding of cast iron can be carried out either layer by layer without the use of supporting elements, or using
studs. The studs are made of steel. Their dimensions are strictly regulated, for example, the diameter should not exceed 40% of the thickness of the cast iron. The protrusion of the stud above the metal is limited to 4-6 mm, and the distance between the studs should not be more than 6 diameters. The amount depends only on the size of the connection, but not more than 25% of the fracture area

We recommend! What and how to weld aluminum

2. Cutting edges.

Note! The edges should not have a sharp cut at the junction of two parts of metal; the optimal shape is spherical.

How to weld a ceiling seam using an electrode?

3. Electrodes must be special. It is almost impossible to weld such metal with conventional electrodes on steel, so it is worth purchasing an electrode with the addition of copper, chromium, nickel and other alloys that facilitate welding onto fastidious cast iron.

Welding process

In the previous paragraph, we discussed the preliminary preparation, and before starting welding, we need to consider the main technological points:

Connection polarity is reverse;
The power of the welding machine is minimal for a given electrode thickness;
The length of one continuous weld should not exceed 30 - 50 mm;
It is necessary to prevent overheating of the metal due to frequent breaks;
The first and last layers of multilayers are hammered with minimal force.

The table below will help you decide on the welding mode:

We have considered the main preliminary points, but the main question remains: “How to cook cast iron using electric welding?” There are two ways: on studs or in layers. Let's look at each option separately.

Welding cast iron using an inverter using studs

After installing the studs, you can begin welding the seam. Metal is placed layer by layer around each pin to form a patch. You can prevent heating above 80 degrees by doing the work in a checkerboard pattern or alternately at opposite ends. The final point in this type of welding is the connecting seam, which connects the welded metal between the studs.

Multilayer welding

First you need to make sure that the chamfers are created correctly. Then, using a special electrode, observing the temperature regime, we begin to fuse the first layer. It is fundamental and will determine the success of further work.

Each layer, while still hot, must be hammered.

If there is access to the back side of the part, then after the first layer on one side you should turn the product over and fuse a similar seam on its back side and only then proceed to complete the multilayer welding of the upper and then the lower part.

We recommend! Possible causes of welding electrodes sticking

Surfacing must be done from the edges, and many layers must be gradually created. The main thing is not to forget to forge each layer. If you don’t know how to check the temperature of a part, then use the random technique. It consists in forming a seam alternately at different joints. When the weld is completely ready, the surface deposited on the cast iron must be ground.

If you are faced with the need to weld cast iron and you only have an inverter, then at home you can repair cracks or apply patches to non-load-bearing structural elements. You will already have almost everything you need, such as a mask, protective gloves and clothing.

You will only have to purchase special cast iron electrodes, or make them yourself. This article describes two ways to weld cast iron at home. Which one suits you best – decide for yourself.

But remember - when there is a need to restore a product that requires heavy loads, it is better to turn to professionals.

Source: https://rem-serv.com/kak-privarit-chugun-k-metallu-prostym-elektrodom/

How to weld cast iron with metal

You must be logged in to post a comment.