What is Polarity in Stick Welding?

What is Polarity in Stick Welding

So, what is polarity in stick welding? Simply put, polarity refers to the direction of current flow in the welding circuit, and it plays a pivotal role in the quality, penetration, and overall success of your welds.

In stick welding, also known as Shielded Metal Arc Welding (SMAW), polarity impacts how heat is distributed between the electrode and the workpiece.

This choice can make the difference between a strong, clean weld and one that’s weak or poorly formed, so it’s an important concept to get your head around!

What Is Welding Polarity?

Polarity in welding refers to the direction of the electrical current in the welding circuit.

This direction, whether it flows from the electrode to the workpiece or vice versa, significantly influences the welding process.

The choice of polarity affects several key aspects of welding, including heat distribution, penetration depth, and the overall quality of the weld.

In stick welding specfiically, getting the polarity right is crucial because it determines how the arc behaves, how deep the weld penetrates into the metal, and the smoothness of the welding experience.

Direct Current Electrode Positive (DCEP)

Also known as Reverse Polarity, DCEP is where the electrode is connected to the positive terminal of the power source.

In this setup, the majority of the heat concentrates on the workpiece, not the electrode.

This results in deeper penetration and a stronger weld.

DCEP is commonly used for welding thicker metals and for certain types of electrodes that require this polarity to stabilize the arc and ensure proper slag coverage.

Direct Current Electrode Negative (DCEN)

DCEN, or Straight Polarity, involves connecting the electrode to the negative terminal.

Here, more heat is generated on the electrode rather than the workpiece.

This leads to faster melting of the electrode and a shallower penetration, making it ideal for thin metals or for processes where less heat input to the workpiece is desired.

DCEN is often favored for its smoother arc and better control, especially in applications requiring precision.

Alternating Current (AC)

Alternating Current switches between positive and negative polarity, typically many times per second.

This offers a balance between the deep penetration of DCEP and the faster electrode melting of DCEN.

AC is particularly useful in situations where the magnetic fields could disturb the arc in direct current modes, like when welding some types of ferrous metals.

It’s also a go-to choice for welding materials that are prone to cracking or when welding on painted or rusty surfaces where arc blow (a welding defect) can be a problem.

Thank you to TimWelds for the video.

Choosing the Right Polarity

As I’m sure you’re understanding, it’s really important to choose the right polarity.

We’ve compiled some useful information below to help you out!

Direct Current Electrode Positive (DCEP)

Characteristics and Benefits:

  • Known as Reverse Polarity.
  • Offers deep penetration and strong welds.
  • Concentrated heat on the workpiece for a deeper weld pool.
  • Ideal for thicker materials.
  • Stable and consistent arc, aiding clean and controlled welding.

When to Use DCEP:

  • Most stick welding applications.
  • Suitable with electrodes like E6010 and E7018.
  • Perfect for tasks requiring strong penetration (e.g., structural steelwork, heavy equipment repair).

Direct Current Electrode Negative (DCEN)

Features and Advantages:

  • Referred to as Straight Polarity.
  • More heat directed towards the electrode, less on the workpiece.
  • Leads to a cooler weld pool with shallower penetration.
  • Beneficial for thinner materials.
  • Reduces distortion and warping in thin metals.
  • Focused arc, easier to control for precision tasks.

Applications for DCEN:

  • Sheet metal work or automotive repairs.
  • Compatible with electrodes like E6012 and E6013.
  • Ideal for low heat input requirements and smooth arc welding.

Alternating Current (AC)

Properties and Usage:

  • Balances features of both DCEP and DCEN.
  • Switches between positive and negative poles.
  • Balances deep penetration and moderate electrode melting.
  • Minimizes arc blow issues in magnetic fields.

Best Used For:

  • Welding metals with residual magnetism or in awkward positions.
  • Working on not perfectly clean surfaces, like rusted or painted metals.
  • Versatile with electrodes like E6011, designed for AC welding.
  • Suitable across various materials and conditions.

Stick Welding Polarity Chart

Below we’ve created an expanded stick welding polarity chart that is designed to serve as a quick reference guide, helping you choose the right electrode for your welding project based on its optimal polarity and characteristics.

Here’s a brief explanation of the table:

  • Electrode Type: Lists common types of electrodes used in stick welding, such as E6010, E6011, E7018, etc. Each type has specific properties and uses.
  • Optimal Polarity: Indicates the recommended polarity (Direct Current Electrode Positive – DCEP, Direct Current Electrode Negative – DCEN, or Alternating Current – AC) for each electrode. Some electrodes work well with more than one type of polarity.
  • Characteristics: Describes key features of each electrode, like penetration depth, arc stability, ease of use, and special attributes like low hydrogen content or suitability for dirty or rusty metal.
  • Common Applications: Provides examples of typical uses for each electrode, guiding you in selecting an electrode that matches the demands of your specific welding task, such as general fabrication, repair work, or heavy industrial applications.
Electrode TypeOptimal PolarityCharacteristicsCommon Applications
E6010DCEPDeep penetration, ideal for dirty or rusty metalPipelines, shipbuilding, outdoor repairs
E6011AC, DCEPAll position welding, good for dirty/rusty metalGeneral fabrication, repair work, outdoors
E6012AC, DCEP, DCENSmooth arc, moderate penetration, all positionsSheet metal, irregular joints
E6013AC, DCEP, DCENEasy to use, minimal spatter, all positionsHome repairs, light fabrication
E7014AC, DCEP, DCENEasy slag removal, good for poor fit-upSheet metal, build-up work
E7018AC, DCEPLow hydrogen, prevents cracking, good for high-strength weldsStructural steel, industrial applications
E7024AC, DCEPHigh deposition rates, suitable for flat or horizontal weldsHeavy sections, non-critical applications
E7028AC, DCEPHigh deposition, efficient in flat and horizontal positionsStructural steel, heavy sections
E308LAC, DCEP, DCENStainless steel electrode, minimal spatterStainless steel fabrication
E6019AC, DCEP, DCENGeneral-purpose electrode, works well on poorly prepared surfacesGeneral repairs, light fabrication
E7027DCEPHigh iron powder content, deep penetrationHeavy welding, bridge construction

What is Straight and Reverse Polarity in Welding?

In welding, “straight” and “reverse” polarity refer to the direction of the electrical current in relation to the electrode.

  • Straight Polarity: Also known as electrode-negative (DCEN), this means the electrode is connected to the negative charge. With straight polarity, the welding process experiences a faster electrode melt-off and a quicker deposition rate. This makes it suitable for welding thinner materials, as it provides less penetration, reducing the risk of burning through the metal.
  • Reverse Polarity: Also known as electrode-positive (DCEP), in this setup, the electrode is connected to the positive charge. Reverse polarity results in deeper penetration into the workpiece, making it ideal for welding thicker materials where a strong, deep weld is needed.

The choice between straight and reverse polarity impacts not just penetration and deposition rate, but also the overall quality and characteristics of the weld.

The type of shielding gas used can influence the weld’s outcome when combined with these polarities.

For instance, certain gases might work better with one polarity over the other, affecting aspects like arc stability and weld bead appearance.

Frequently Asked Questions:

Which polarity is best for welding?

Determining the “best” polarity for welding depends largely on the specific welding use case, material being welded, desired weld characteristics, and the type of electrode used.

Here’s a quick breakdown:

  1. Direct Current Electrode Positive (DCEP): Often considered the most commonly used polarity in stick welding, DCEP is excellent for creating deep penetration into the workpiece. This makes it ideal for thicker materials and for electrodes that require a deep weld pool. It’s often used in structural welding, heavy repair work, and with many common electrodes like E6010 and E7018.
  2. Direct Current Electrode Negative (DCEN): DCEN directs more heat towards the electrode rather than the workpiece, resulting in a cooler weld pool with less penetration. This characteristic makes it suitable for welding thinner materials where excessive penetration could be detrimental. It is often used in applications like sheet metal work or welding thin tubes and pipes.
  3. Alternating Current (AC): AC is useful in situations where DCEN and DCEP are not as effective, such as when welding on magnetized materials or when dealing with arc blow (a disturbance of the welding arc due to magnetic fields). It’s a good all-around choice when welding materials like certain ferrous metals or working on surfaces that aren’t perfectly clean.

How do you check the polarity of a welder?

To check the polarity of a welder, locate the output terminals where the welding leads connect.

They are typically marked with a “+” for positive and a “-” for negative. Connect the electrode holder to the positive terminal for DCEP (Direct Current Electrode Positive) or to the negative terminal for DCEN (Direct Current Electrode Negative).

Some welders have a switch or a setting in the control panel to change polarity; refer to the welder’s manual for specific instructions.

Do you stick weld on DC+ or DC?

In stick welding, you can weld using either DC+ (Direct Current Electrode Positive, also known as DCEP) or DC- (Direct Current Electrode Negative, also known as DCEN).

The choice between DC+ and DC- depends on the electrode being used and the desired characteristics of the weld.

  • DC+ (DCEP): This is the most commonly used polarity in stick welding. It provides deeper penetration and is often used for welding thicker materials. It’s the preferred polarity for many types of electrodes, such as E6010 and E7018.
  • DC- (DCEN): This polarity results in less penetration compared to DCEP. It’s typically used for welding thinner materials or when less heat input is desired. DCEN is often chosen for its smoother arc and better control in certain applications.

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