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Types Of Welding Rods And Their Applications

Are you a welding enthusiast looking to explore the different types of welding rods and their various applications? We can help! In this blog post, we’ll be going over an in-depth explanation of how the specific properties of various welding rods affect their uses as well as detailing which kinds are best suited for particular jobs. Without further ado, let’s get started and discover why welders rely on different types of welding rods for different projects.
 

 

What is Welding Rod?

A welding electrode is another name for a welding rod. A metal rod with a metal and mineral powder coating is a welding rod. Stick welding, sometimes referred to as shielded metal arc welding (SMAW), uses welding rods. The rod serves as an electrical conductor for the arc as well as a source of filler metal for the workpiece.

The use of welding rods might be either consumable or non-consumable. Consumable rods break down or melt to create the adhesive that joins two metal parts. Non-consumable rods, on the other hand, merely offer the base metals enough catalytic reaction to promote their fusing in an oxygen-rich air environment. Any continuous weld bead’s length is inversely related to the welding rod’s length.

Types of Welding Rods and their Uses:

  • Consumable and non-consumable electrodes fall into several categories.
  • Consumable electrodes are used by arc welders, MIG welders, and TIG welders.
  • Consumable electrodes, as opposed to non-consumable electrodes, melt into the base metals.
  • A weld pool is formed, and the two base metals are fused by welders using electrodes to create an electric arc.
  • The electrode is made of a thin metal wire available in different lengths, diameters, and coatings.
  • SMAW and TIG welding employ electrodes that resemble long wire rods, whereas MIG welding uses a spool of wire that the MIG machine feeds into the welding gun.
  • A welder maintains a TIG or SMAW electrode throughout the welding procedure rather than using machine feeding.
  • While some electrodes are appropriate for various metals and currents, it’s important to consider which electrode types are made for multiple metals and circumstances.
  • The user is likelier to use a consumable electrode unless TIG welding is the only emphasis. However, if one is to use an arc welder with carbon electrodes, there is an exemption. Carbon graphite is used to make non-consumable carbon electrodes.

Non-Consumable Electrodes

Electrodes made of tungsten and carbon are examples of non-consumable electrodes. In industrial and domestic applications, tungsten rods for TIG welding are more prevalent than carbon rods.

  • Carbon Electrode:

An older and less popular type of welding is carbon arc welding (CAW). CAW is a process that isn’t likely employed in a welding shop or a DIY workshop, although it is still in use today. The American Welding Society (AWS) no longer includes CAW requirements. The US military’s many branches are still heating and cutting metal with CAW. In contrast to a typical arc welder setup, CAW uses two carbon electrodes that cannot be consumed. Unlike the arcs produced by other techniques, the enormous arch created by the carbon electrodes is far more difficult to regulate. The enormous arc can heat metals and carve channels or holes into them, but it is not intended to perform precise welds on thin metals.

  • Tungsten electrodes:

The most common non-consumable electrodes are made of tungsten and are used with Tungsten Inert Gas (TIG) welders. Pure tungsten, a combination of tungsten and zirconium or thorium, is used to make tungsten electrodes. Pure tungsten electrodes are appropriate for smaller applications on thinner metals that don’t require a lot of amperages. Although they perform well on heavier metals, tungsten/zirconium electrodes are not as robust as tungsten/thorium. The most common kind of tungsten electrodes, tungsten/thorium, creates the strongest welds with high amperage.

  • Consumable Electrodes

The consumable electrode is the most prevalent type of electrode and is utilized by shielded metal arc welders and inert metal gas (MIG) welders (SMAW, also known as stick welders and arc welders). Consumables melt while welding, unlike non-consumable electrodes.

The thin wire used for MIG electrodes is automatically fed into the welding gun by the MIG machine. Fully automatic MIG welders are run by robots, whereas human welders run semi-automatic welders.

MIG wire is not flux-coated because MIG machines use a shielding gas to protect the weld. One of the industry’s top picks is the Forney Easy Weld 261 MIG Welder because it strikes the ideal combination between price and quality.

Arc welders utilize consumable electrodes or sticks instead of shielding gas to create strong welds. Bare and coated electrodes are the two consumable electrodes for arc welding. For welding manganese steel, bare electrodes, which lack a flux layer to shield the weld pool, are frequently employed. Arc welders prefer coated electrodes, which are split into three categories. Electrodes with light coatings, medium coatings, heavy coatings, or protected arc electrodes.

  • Light-Coated Electrodes:

     

Light-coated electrodes have a thin flux coating, as the name suggests. The flux shields the weld pool from contaminants, including phosphorus, sulfur, and oxides, even though it doesn’t provide a trustworthy shielding gas. In addition to stabilizing the electric arc, light-coated rods produce less slag than medium or heavy-coated rods. Light-coated rods are not appropriate for metals with high contamination levels that need a shielding flux since they have a coating factor of 1.25.

  • Medium-Coated Electrodes:

     

Welders of all skill levels typically use medium-coated electrodes, such as low-hydrogen rods. Offshore drilling operations, bridge construction, commercial building construction, and pipeline welding are typical uses for medium-coated rods. Medium-coated electrodes, which have a coating factor of 1.45, are characterized by readily removed slag, excellent arc control, and the capacity to weld in all positions.

  • Heavy-Coated Electrodes:

     

The most flux is found in heavy-coated electrodes with a coating factor of 1.6 to 2.2. When the coating is fired in the weld pool, an efficient shielding gas is produced to safeguard the weld. Three different materials, cellulose, minerals, and a mix of cellulose and minerals, are used to make the rods.

Different categories of Welding Rods 

  • 6010:

Popular 6010 electrodes are widely used. They are employed in deep penetration welding, which requires extremely high power densities of up to 1 megawatt per square centimeter. E6010 electrodes are primarily utilized in pipe welding and applications, including shipyards, water towers, steel castings, field construction, and steel storage tanks in light of this. But it’s crucial to remember that they can only be used with direct-current welding equipment (DC). They also have a very tight arc, which makes them challenging to handle, especially for novice welders.

  • 6011:

The 6011 electrode is unique because it can be utilized with either alternating or direct current. This provides tremendous ease because the consumer can quickly switch between different current types to see which performs best. Because of this, it is the ideal electrode to use for welding thicker materials. This also explains why welding jobs involving painted, grimy, or oily surfaces need 6011 electrodes. This electrode’s disadvantage is that it produces flat weld beads, which create ripples and rather uneven finishes. This can be a problem if one wants a finished product that looks good.

  • 6012:

The 6012 is a multipurpose welding rod that excels at bridging, especially in applications with poor fit-up. Additionally, this electrode is renowned for producing a good, stable arc and operating at high currents with little spatter. Even better, it can use both AC and DC power sources. However, 6012 electrodes have two significant drawbacks. First, they work best for thin or shallow penetration. They also produce thick waste material from smelting, necessitating more post-welding cleanup. This welding rod is frequently used for non-critical welding, connecting open joints, welding repairs, and joining rusted carbon steel sheets.

  • 6013:

Another widely used electrode, this one, produces a gentle arc with minimum spillage. The 6013 has an easily removed slag and is frequently used for welding with moderate penetration. It’s also crucial to remember that it works with both alternating and direct currents. With these qualities in mind, this kind of electrode is utilized when welding activities are brief or irregular. It works perfectly for applications requiring a change in position because it produces a fairly solid and smooth arc. These include welding mild steel surfaces overworked or worn out, welding sheet metal, and building and repairing ships. Electrodes made of 6013 are also employed in general and light fabrication.

  • 7018:

One of the most flexible welding rods, it is primarily utilized for welding low to mild-carbon steel. As previously discussed, this electrode creates a considerably stronger weld that can endure up to 70,000 psi. Another important characteristic of the 7018 welding rod is that it is typically covered in a low-hydrogen compound made of iron. This substance is what vaporizes, shielding the weld bead from moisture and air damage in the process. This welding electrode can be used in all four positions and with AC and DC power sources. These qualities have made the 7018 useful for structural welding. This refers to the welding needed for industries, bridges, powerhouses, and energy-generating plants.

  • 7024:

This welding rod’s high iron powder concentration is its distinguishing feature. This essential characteristic greatly accelerates the deposition rate, which facilitates welding. The most common application for 7024 rods is high-speed flat or horizontal welding. They work especially well in applications that call for a clean finish with subtle ripples. For beginners, the 6013 and 6011 welding rods are ideal. The 6011 produced almost no slag. Extremely simple to strike but required the proper ratio of melting through to connect the pieces. Currents up to 225 amps can be employed with the 7018 arc welding rod. The user must follow the manufacturer’s instructions for establishing the welding wind because the amp requirements for 7018 rods differ between manufacturers. The 7018 rod, made of mild steel, has a low-hydrogen, iron-based flux coating that vaporizes to protect the molten weld bead from contamination by air and moisture. It is frequently employed for welding carbon steel for all purposes.

Varieties of Welding Rods:

The following are the typical welding rod types:

Low Hydrogen Carbon Steel Electrode: 

It is a main coated low hydrogen iron powder electrode for low-temperature applications. It is an all-position electrode for welding medium tensile and fine-grained carbon steels. These welding rods provide outstanding weld beads for welding and cutting thick materials.

It also allows simple generation and retention on the arc and outstanding endurance. These are also effective in joining low alloy and carbon steels. After a prolonged post, the electrode also has remarkable mechanical qualities.

Mild Steel Electrodes: 

High-quality soft steel electrodes have negligible carbon steel deposits. Under all circumstances, this electrode functions at low OCV (50V) AC. They possess the significant tensile strength needed to maintain a lengthy arc. These are extensively utilized in manufacturing ships, pipelines, rail carriages, and automobiles. Additionally, it offers a gentle weld bead formation, little spatter, great slag detachability, and a smooth, stable welding arc.

Aluminum Welding Rods: 

These aluminum welding rods serve multiple purposes and can combine different aluminum alloys and pure aluminum. It enables rich, dense, porosity-free, crack-free deposits and high-quality welds.

Almost any non-ferrous metal can be welded with aluminum welding rods. They operate smoothly, weld quickly, produce little spatter, and are simple.

Stainless Steel Electrode: 

It is a fundamental electrode that delivers a weld metal in austenitic stainless steel with low carbon content. It is intended to provide and maintain a consistent weld quality regardless of how the weather and temperature affect it.

These rods provide smooth welding, high corrosion resistance, and simple slag removal. Welding electrodes produce spectacular, long-lasting project work demonstrating excellent quality and expertise.

Bronze Welding Rods: 

Nearly all repairs to bronze workpieces or the joining of copper to metals that are not compatible are done using bronze welding rods. These rods are also employed in brazing, which calls for the use of filler metal. To bridge the space between the workpieces in this instance, it has a lower melting point than the nearby metals.

How are Welding Rods named?

An alpha-numeric system for naming welding electrodes was developed by the American Welding Society (AWS). This is the primary system used to identify welding rods in the United States and other nations. As suggested by the name, this alpha-numeric technique consists of letters and numbers, typically engraved on the side of each welding rod. One will encounter words like E6010, E7018, and others. The naming approach operates as follows:

The word “electrode” is represented by the large letter “E” at the start of the name. The minimum tensile strength of the weld, expressed in pounds per square inch, is indicated by the next two digits (Psi). The number 60 in E6010, for example, indicates that the rod creates beads with a minimum strength of 60,000 psi. In other words, the final weld bead can withstand the 60,000 pounds of force needed to tear it apart.

The third value is the total number of possible places for the welding electrode. Four positions are comfortable: flat, horizontal, vertical, and overhead. For instance, a rod can be utilized in any position with a one, but a 2 restricts its use to flat or horizontal positions. The final digit displays the coating and welding current type that can be utilized with the rod (alternating current, direct current, or both).

How are Welding Rods numbered?

The electrodes’ numerical classification system may appear perplexing at first, but once there is knowledge regarding what the numbers mean, buying electrons will be simple. The system, created by the AWS, provides information regarding the amount of pressure the rod can withstand, the ideal welding position, the makeup of the flux, and the ideal current to employ with the rod. In welding, the most used rods are 7018, 7014, 6013, 6011, and 6010.

The first two figures, using a 7018 rod as an example, can be used to calculate the rod’s tensile strength. One may determine that the weld can endure 70,000 pounds of pressure per square inch by multiplying 70 by 1000. The third number on the electrode indicates the electrode’s ideal position for welding. Just 1, 2, and 4 are employed.

The electrodes can be utilized in any position when the electrodes are numbered 1, 2, or 4. The number 4 denotes an overhead or vertically up or down position. This implies that the rod can be used in all situations in the case of the 7018 rods. The last value denotes the proper current to utilize along with the flux material. 8 denotes the rod’s low hydrogen potassium and iron powder composition. It indicates that AC, DC-, and DC+ are the electrode’s good currents. The electrode’s covering is constructed from a variety of substances. The number categorization of an electrode contains a wealth of information.

Manufacturers of electrodes publish complete specs on the packaging, which should address all concerns. It is important to check the specs before starting a welding project and before a welding equipment setup. Most instructions also explain how to set the machine’s amperage and what metals are appropriate for the electrode.

How to store and work with Welding Rods?

When one buys electrodes, there are a few things that any consumer should be aware of. Electrodes must be handled carefully because they are brittle parts. Although electrodes have metal cores, they can flex or break depending on the metal. Welds made with rods that are not physically sound when utilized won’t hold up. The flux keeps the weld pool safe and is necessary for producing strong welds.

When one buys rods, they are placed in an airtight container, and if they are left without protection for more than a few hours, they start to deteriorate. Keep the leftover rods in a sealed container while choosing an electrode for welding. The flux will degrade when exposed to humid environments, depending on the makeup of the rod. The change will become a mushy mess if it uses too much hydrogen or oxygen. If the user works outside, it can be difficult to avoid the humidity. By opening the rod’s container just before welding, one can try to reduce the electrode’s exposure to the atmosphere.

How to select a Welding Rod?

Even if one knows the many welding electrode types, selecting the right one for a certain application might be challenging. Several other things to think about include the following:

  • The Base Metal:

The base metal’s composition is one factor that should be considered. Finding a welding rod closely resembling the base metal is the main objective. The likelihood of a solid and stable weld occurring is increased by doing this. If one is unsure of the base metal’s configuration, the following factors should be considered and taken into account:

  • Appearance:

Identifying whether one is working with a broken piece of metal or a component is crucial. After doing so, one should examine the texture; a rough or grainy surface indicates that the object is made of cast metal.
Magnetic vs. non-magnetic: Another way to differentiate the base metal is by determining whether the substance is magnetic. There is a good chance it is alloy steel or carbon steel if it is magnetic. If it’s not magnetic, the base metal could be any non-ferrous alloy made of brass, aluminum, titanium, or copper, austenitic stainless steel, manganese steel, or austenitic stainless steel.

  • Type of spark:

Check the base metal’s spark when it is run against a grinder. Here, the golden rule is that the base metal has a larger carbon content, the more flare there is in its sparks.
Chisel’s impact on the metal A chisel leaves bite marks when used on soft metal like aluminum. Harder metals like cast iron or high carbon steel, on the other hand, cause it to bounce off when struck.

  • Tensile Strength:

It’s crucial to match the welding rod’s tensile strength to the base metals. Failure to do so may lead to weld discontinuities such as cracking. The consumer only needs to look at the first two digits of an electrode’s serial number to determine its tensile strength. A 6011 rod, for instance, creates a weld bead with a minimum tensile strength of 60,000 psi and can thus be used with steel with similar tensile strength.

  • Welding Current:

Some welding rods handle alternating and direct currents, whereas others only work with one. Check the fourth digit in an electrode’s name to see what kind of current it can be utilized. This figure displays the appropriate welding current as well as the type of coating.

Different Coatings used in Welding rods:

Since each type of electrode coating has a variety of qualities, each coating’s chemical composition will result in various properties. There are many different coatings, so one should study the best uses for each coating type before deciding which one is best for a particular project.

  • Cellulose Coating

    About 1/3 of these coatings are made of cellulose, while 2/3 are made of other organic compounds. The substance breaks down into three different gases, hydrogen, carbon monoxide, and carbon dioxide, when exposed to the welding arc, strengthening the angle in the process.
    As a result, it enables the current to pierce the metal more deeply, producing stronger welds. Additionally, it releases a gas barrier to shield the weld pool from contaminants. They come in various chemical combinations with special qualities and the finest uses.

  • Mineral Coating

    Mineral coatings leave slag on top of the metal used for welding. Slag has a use, despite appearing to be a bothersome side effect. Compared to an electrode coated in cellulose, the slag of a mineral-covered electrode cools much more slowly. This gives the contaminants time to settle on the metal surface, protecting the weld’s structural integrity.

  • A mixture of Both

    Given that it combines the greatest qualities of both chemicals, cellulose, and minerals, it is a preferred option among fabricators. The chemical variety of these coatings offers several important benefits due to the small number of components and higher number of elements. Welds’ slag and shielding gas protection can be quite helpful, especially when working with fickle base metals.

How are Welding Rods made?

A metallic wire is employed. It is purchased from the low carbon and silicon content metallic wire supplier. These wires are examined in the composition and, if necessary, heat treated to improve the metal’s ductility.

  • Metal Forming:

By dragging the wire through drawing dies, the metal forming process reduces the cross-section of the wire. Then, these metallic wires are removed and formed into certain sizes per the specifications using metal forming equipment. These metallic rods often come in 2.5, 3.15, 4, and 5mm sizes.

  • Straightening and Cutting:

    The feed is given to the machine for straightening and cutting after the metal has been formed. The metallic rod is straightened and chopped to the welding electrode’s prescribed length.

  • Dry Mixture:

The dry mixture contains the flux’s chemical makeup, which will be deposited on the metallic rod. Cellulose, Mica, Titanium Dioxide, Low Carbon Ferro Manganese, Feldspar, and other chemicals comprise most of the chemical composition. These ingredients are thoroughly weighed before preparation, then added to the dry mixer to create a homogeneous mixture.

  • Wet Mixture:

Potassium silicate is weighed and added to create a wet mixture out of the dry mix. This serves as the mixture’s binding agent. The moist mixture is collected and loaded into a hydraulic press to create briquettes. These briquettes are then fed into the extruder’s flux cylinder.

  • Coating the flux by extrusion:

The extrusion press applies the flux coating to the metallic rod. Here, the wire is fed from the wire magazine, and the flux is provided through a cylinder under pressure. The metallic wire is fed sequentially from the wire feeder during the extrusion process. It is thoroughly coated with the flux with a nozzle or die box mechanism that integrates well with the extrusion press. To ensure that the welding rod is formed properly, an eccentricity tester routinely examines the metallic rods that have been coated with flux.
The rods that failed the test are gathered, and the stripping rod is used to remove the flux. These metallic rods may be utilized once more in the procedure. The welding rod’s one end is properly ground and used for holding it by the holder during welding. The electrodes coming out of the press with the help of the conveyor are brushed to make the surface smoother. After some time, these welding rods are fed into the oven for appropriate drying after being collected in the tray for air drying.

  • Baking of the electrode:

The welding electrodes are placed in the tray and fed into the oven to bake. The main purpose of baking is to reduce moisture content, and the baking time varies depending on the electrode size. For the welding electrode to operate correctly, it is advised that the moisture content not go beyond 4%.

  • Grading and Packing:

The type of electrode is printed on the body of the welding electrode when the baking cycle is complete. The finished welding electrodes are finally stored and packaged in the designated boxes.
 

 

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