Many people ask whether it is possible to make an electrode for welding ferrous metals with your own hands at home?
The answer is no. You cannot make a normal welding electrode yourself. Because this is a fairly knowledge-intensive process, and the components included in the coating cannot always be purchased at the nearest store.
What does the great and terrible Internet offer us in this regard?
Numerous welding websites claim that making an electrode is not a problem. Without going into the details of such production, you will need a steel bar, chalk, crushed to a powdery state (fine fractions). Liquid glass (silicate glue) is applied to the rod, then the whole thing is sprinkled with chalk and rolled so that it evenly adheres to the surface of the rod. It turns out chalk layer some thickness. The homemade product is sent to the oven, oven or dried with a hairdryer.
And can you cook with this?
From our point of view it is impossible. You can equally well weld with a nail, rebar or bare metal rod. No difference. The process of such welding is unstable, the seam can hardly be called such, and there will be practically no slag due to the absence of slag-forming elements in the composition of the coating.
If you are going to do it yourself, it is better to use the idea proposed a hundred years ago by two Americans. They came up with the idea of simply wrapping the rod in paper and gluing it onto liquid glass. At least it's easier than messing around with chalk. And the idea is very simple. The paper burns and emits smoke, which protects against the harmful effects of oxygen. Also, such a coating somehow improved ignition and had a positive effect on the stability of the arc... And this, of course, is very doubtful. Since easy ignition electric arc and the maintenance of its combustion occurs due to the low ionization energy of elements such as sodium, potassium and calcium.
In other words, you don’t have to worry about the composition of the coating and the method of application. If you really want to cook, but have nothing, and the shops are all closed for the holidays, take any piece of iron suitable in diameter and length, clamp it into the electrode holder and cook - this process cannot be called welding, but it is quite possible to grab something this way in extreme conditions. At the very least, this is no worse than the options proposed above.
The production and sale of welding electrodes is popular view activities in Russia. Electrodes are a consumable material that is in demand in construction during the construction of reinforced concrete structures, as well as in those areas of industry where it is necessary to connect metal surfaces by welding. Relatively small financial investments at the opening stage and quick payback (from 1 to 3 years) are the main advantages of an enterprise whose activity is the production and sale of welding electrodes.
Our business assessment:
Starting investment – from RUB 2,500,000. and higher
Market saturation is high.
The difficulty of starting a business is 8/10.
Main stages of production of welding electrodes
An entrepreneur opening a mini plant for the production of welding electrodes needs to rent premises, purchase equipment and consumables. But you can buy machines and raw materials only after you have chosen the method of manufacturing the product: coating or crimping.
Generally, technological process, in which a thin coating layer is applied to a metal rod, is not complicated and consists of several stages:
- production of a workpiece - a metal rod;
- preparation of coating mixture;
- applying coating to the workpiece;
- drying.
Production of electrodes at home: coating method
Coating is a method that can be used in the production of electrodes at home in small batches. The main device responsible for quality finished products, is a drying cabinet. The cost of a drying cabinet varies from 1,230 rubles. (simple pencil case) up to 22,000 (powerful electric oven).
Materials used for the manufacture of electrodes:
- special wire of a certain diameter;
- chalk with additives;
- potassium or sodium lump.
Special steel wire for making electrodes, required diameter and length, straightened and cut into equal pieces. All operations are carried out using automated equipment.
The surface of the resulting workpieces must be thoroughly cleaned sandpaper. Removed during processing upper layer metal, and the surface of the wire becomes clean and slightly rough, which guarantees high-quality adhesion to the coating.
The coating solution is a homogeneous mass mixed from different components, one of which is liquid glass made from silicate block. It is important to remember that all substances must be in powder form.
Chalk and other additives undergo certain stages of crushing in a roller or crushed stone crusher:
- rough crushing, as a result of which substances are divided into large pieces;
- grinding to obtain a powdery mass (fine grinding);
- sifting using special sieves.
This will create a homogeneous mixture that will lie evenly on the electrode and adhere well to metal surface blanks. Next, the metal rod is lowered into ready solution and then double dried.
Manufacturing of electrodes by crimping method
But the coating method used at home is not suitable for making electrodes on a large scale industrial production. Hardly large companies in need of large quantities welding material, will buy “handicraft” products, without a certificate and accompanying documentation, even if they are of good quality.
Therefore, in an enterprise that has plans for further development and expansion, it is preferable to use electrode production technology using the crimping method. Since the product obtained in this way corresponds to the maximum modern requirements and standards for welding materials.
Crimping is the production of welding electrodes using special presses, where they are exposed to high pressure(from 300 to 650 kgf/sq. cm). The process consists of pulling a metal workpiece (electrode wire) through the holes located in the installation cylinder, which is filled with a coating solution.
Finished products are checked for defects and the ends are cleaned. Only after this are the electrodes labeled and packaged. The waste remaining after the operation of the scrap cleaning machine is sent for processing and then put into production of the next batch of products.
To organize a mini workshop, you need a line for the production of medium-power electrodes, including:
- rod feeder;
- GEP – hydraulic electrocoating press;
- stripping installation.
Additional devices:
- MPE – electrode supply mechanism;
- MZT – stripping and transportation mechanism;
- Ballast – automatic straightening and chipper, equipped with a receiving hopper and a wire unwinder;
- BP – briquette press;
- MOB (10) – a mechanism for cleaning raw defective electrodes;
- MS (50) – wet mixer.
The price of equipment for electrodes varies from 6,800,000 to 8,000,000 rubles.
It should be noted that the coating is a necessary component of the electrode, facilitating uniform melting of the metals being welded. And the slag crust formed during the welding process blocks the access of oxygen to the connecting seam, which avoids rapid loss of temperature on the surfaces being welded. The result is a perfectly smooth seam, without bubbles and microcracks.
Production of graphite electrodes
The production of carbon electrodes is considered more complex, the production of which requires large quantity energy (current 60-120 kA), complex expensive equipment and time. This determines high cost finished products.
Carbon or graphite electrodes are made from the following materials:
- low ash petroleum coke (about 85%);
- electrode strike (about 15%);
- coal tar pitch (as a binder).
The components go through the stages of crushing, calcination, grinding, fractionation, dosing and mixing. Next, the electrode mass is processed in powerful horizontal presses. The resulting green electrodes are dried, fired and graphitized.
Firing is carried out for 12 - 33 days at temperatures from 1525 to 1625 K without access to oxygen. As a result, coal tar pitch turns into coke, providing increased thermal conductivity and electrical conductivity of the finished product, as well as improved mechanical characteristics electrodes.
Graphitization lasts more than 100 hours at temperatures from 2700 to 2900 K.
The most expensive part of the project is the acquisition of a production line. Therefore, before buying equipment for the production of welding electrodes, it is necessary to carefully analyze the state of the market in the opening region, calculate the amount of starting investments and choose optimal technology manufacturing.
It is advisable to first find clients, who are usually:
- specialty stores;
- companies engaged in the production of metal structures;
- private workshops.
You can save money by purchasing used equipment. But in this case, you need to carefully check the documentation (technical condition, number of repairs), find out about the reasons for the sale.
Calculation of profits from the production and sale of electrodes
For a novice businessman who does not have the opportunity to purchase a modern production line, it is better to start with small production. But this will also require renting premises for installing equipment (for example, drying cabinet, press and containers for preparing the coating mixture) and purchasing a minimum set of devices. In this case, the costs will be from 2,500,000 rubles. and higher. This includes the purchase of equipment, delivery, launch, purchase of raw materials, employee salaries, advertising, packaging, etc.
According to experts, the profitability of such a business is 30%.
The cost of electrodes varies depending on the region and averages 400 rubles. per package (5 kg) or 80 rub. for 1 kg. Cost - about 50 rubles. for 1 kg. By using modern devices You can produce about 500 kg of finished product per day.
From here:
- Revenue per day will be about 25,000 rubles. (500x50),
- per month – 750,000 rub.
Based on profitability, net profit will be about 230,000 rubles. per month (750,000 / 30). The enterprise will fully pay for itself in 10-12 months.
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 site article is about MMA welding mmasvarka.ru we will talk about what types of cast iron electrodes 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.
EMES - for their manufacture, low-carbon wire is used, onto which a three-layer coating is applied during the manufacture of EMES electrodes. Due to this, during the burning of the electrode, a gas protective layer is formed, which protects Weld from the formation of air bubbles and oxidation.
Ficast NiFe K electrodes - a special type of electrodes for welding cast iron and steel together. They are iron-nickel rods for high-quality welding of cast iron and steel.
MNC-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 orSSSI 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 screw copper wire to conventional 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, make sure that homemade electrodes are calcined in 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 to achieve best quality performance of work.
Anyone who has ever dealt with welding has probably paid attention to the clamping of the electrode - one awkward movement, and the rod changes angle, or may even fall out. Of course, professional welders do not encounter such situations, but an amateur would like something more reliable - rigid fixation of the electrode will allow him to perform welding work efficiently and accurately.
What materials will you need?
- Bolt (35 mm) and stud (70 mm) with thread 12;
- Extended nut (25-30 mm);
- Two regular nuts;
- Coupling nut (wing);
- Plastic holder (side handle) for an angle grinder.
Preparatory work
First of all, mark the center of the elongated nut, and then clamp it in a vice. With help conventional drill drill out through hole. The diameter of the drill should be about 1/3 larger than the possible thickness of the electrode. 6-8 mm. Make sure that the drill is strictly perpendicular to the edge of the nut.
Then we clamp the bolt in a vice and use a grinder to cut off the head. We weld a wing nut in this place. The length of the free thread must be no less than the distance from the edge of the long nut to the center of the hole made.
We unscrew the handle from a non-working angle grinder, drill or other similar tool.
The inner bolt is easily knocked out.
We clamp it in a vice and drill a hole for our stud.
Now you can start assembling.
Assembly of an exclusive reliable electrode holder
We screw the stud and the wing bolt into the wide nut so that they do not reach the edge of the hole made.
Next, we insert the entire structure into the handle and visually mark the place to which the fixing nut is to be tightened.
Then we twist the double nut, and on the opposite side we install the nut to the desired depth. We wind the wire going to the welding machine and clamp it with another nut, using two open-end wrenches for this.
We place the pin with the wire inside the handle and finally fix it with a double nut with outside. Insert the electrode into the hole and tighten the wing bolt with a little force. Now you can start welding.
What you shouldn't forget
Throughout all the work, tools such as a drill, grinder and welding machine. All of them require increased attention, because non-compliance elementary rules safety and neglect of personal protective equipment (work gloves, goggles, welding mask and long-sleeved clothing made of non-flammable materials) can cause injuries, sometimes quite serious.
Trial
Having carried out test welding, I can say with confidence that our homemade holder is a full replacement for industrial analogues. It securely fixes the electrode, and in cases of sticking it is quite easy to detach it from the surface to be welded (in the factory handle it often jumps out of the clamp and remains welded to the workpiece).
The only drawback can be considered the fact that this handle is made of plastic, albeit durable. During prolonged use, heating occurs in any case, and the handle may become deformed. Otherwise, it turned out to be an excellent handle, the cost of which is three nuts and two bolts.
It is desirable that the wire be close in composition to the metal being welded. Otherwise, there is a high risk that the seam will turn out to be short-lived and of poor quality. Otherwise it will completely fall apart.
Today, 56 grades of electrode wire are produced. They all have different chemical composition. They can be divided into three main groups.
The first group is carbon wire. It contains up to 0.12 carbon. This wire is used to weld low and medium carbon steel.
The second group is wire for low-alloy steel. It contains nickel, chromium, molybdenum, titanium, manganese and others chemical elements. Well, the third group includes high-alloy wire.
Special tables can help you choose the right type of wire. According to the contents symbols It is easy to calculate the appropriate chemical composition of the wire.
Electrode wire is available in diameters from 0.3 to 12 millimeters. Most often used with a diameter of three to six millimeters. The wire must always be clean.
Electrode coating
The electrode coating is a mixture of various components applied and fixed to the electrode rod.
The inventor of the coated electrode is the Swedish engineer Oskar Kjellberg. He came up with the idea of coating the wire with silicate powder.
In 1908, German Imperial Patent No. was issued to Kjellberg. 231733 "Electrode and procedure for electrical soldering." The patent states that the purpose of the coating is to “protect the molten metal from oxygen and nitrogen in the air, ensure the proper physical and chemical condition of the weld, and enable welding in all spatial positions.”
Today, two types of electrode coatings are most often used: thin or stabilizing, and thick or high-quality. The stabilizing coating ionizes the arc gap, thereby facilitating the process arc welding.
It weakly protects the molten metal from harmful effects air. But it still gives a relatively acceptable quality of the weld, although inferior to the base metal. The simplest stabilizing coating is chalk diluted in liquid glass (sodium silicate).
A high-quality coating regulates metallurgical processes during welding and improves the properties of the deposited metal. Compound high-quality coating quite complicated. It contains slag-forming, gas-forming, deoxidizing, alloying and stabilizing components, steel powders.
Nowadays, the most common electrodes in our country are those with calcium fluoride or, with similar properties, rutile coating. When melting, such electrodes produce flux that protects weld from the harmful effects of the atmosphere.
In Western countries, cellulose-coated electrodes have also become widespread. Metal rod wrapped in plain paper, which is soaked liquid glass and then dried. Such electrodes emit a lot of gases that protect the metal and the weld pool.