Guide to Welding Positions

Welding is a fundamental skill that plays a role in a number of industries, including the construction, manufacturing, automotive, aerospace, and energy production sectors. Understanding welding positions is essential for creating high-quality welds. This guide will provide you with the basic knowledge you need to understand welding positions as well as their applications, their numerical designations, and the techniques necessary to perform welds in different positions.

What Are Welding Positions?

Welding positions are the various orientations in which it is possible to perform welding on any given joint. The position of the joint and the direction in which the weld is made will have a significant impact on the welding technique as well as on the quality of the weld.

It is important to learn welding positions for several reasons:

Versatility. By learning different welding positions, welders understand how to adapt to any scenario and are capable of completing a wide variety of challenging welding projects.
Quality. Understanding the different welding positions enables the welder to determine the best technique to utilize to obtain high-quality welds.
Code Compliance. Many welding codes — for example, the AWS (American Welding Society) and the ASME (American Society of Mechanical Engineers) — specify what qualification tests are necessary to ensure welders are capable of performing sound welds on jobs regulated by the applicable codes.

Basic Welding Positions

The basic welding positions form the foundation of welding techniques and are often a determining factor in things like quality, productivity, skill, and technique.

Welding positions are noted by their numerical designation and the type of weld joint being performed. Note that “G” refers to a groove weld and “F” signifies a fillet weld.

Flat Position (1G and 1F)

In the flat position, the axis of the weld joint is horizontal and the weld is made on the top side of the joint. A weld in the flat position is the easiest weld joint to perform. Gravity keeps the molten weld metal in place, with little extra effort required by the welder. It is generally advisable to weld as much as possible in the flat position for two main reasons:

Productivity - As the molten weld puddle stays in place far more easily in the flat position, the welder can use much higher temperatures and larger electrodes and/or filler metals, thus increasing deposition rates. (Deposition rate refers to how much filler metal may be deposited into the weld joint in any given unit of time.)
Skill and ability - Since gravity is helping to keep the molten weld puddle in place and little to no extra effort is required by the welder, it takes less skill to make welds in the flat position. Beginner level welders often learn on weld joints in the flat position before they advance to more challenging welding positions.

Horizontal Position (2G and 2F)

In the horizontal position, the weld is performed on the side of the joint and the weld axis is horizontal. This dynamic requires the welder to adjust heat and travel speed to keep excess molten weld metal from falling out of the weld joint.

The photo above shows a welder making a fillet weld in a beam connection in the horizontal, 2F position.

Vertical Position (3G and 3F)

In the vertical position, the weld joint is oriented straight up and down with the axis of the joint in the vertical position. Vertical position welding requires careful control of the welding parameters to keep the molten weld metal in the weld joint and to prevent it from falling out. Heat, travel speed, and filler metal size are all important factors in vertical position welding.

Uphill or Downhill in Vertical Position Welding

The welder may start the weld at the bottom going upward (as is the case in structural steel welding) or at the top going down (as is common in pipeline welding). The applicable welding code, the welding process, and the designated filler metals are a few of the many factors that determine if a welder will use vertical up or vertical down welding.

Overhead Position (4G and 4F)

Overhead position welding is performed on the bottom side of the joint, with the welder looking up from underneath. Welding in the overhead position may be the most challenging for the simple fact that gravity adversely impacts the weldability of the joint. The welder must use sufficient heat to ensure proper weld penetration but not use so much that there is too much weld metal in molten form, which would cause excess weld metal to fall out. Again, heat, travel speed, filler metal size, and technique influence whether welds made in the overhead position are successful.

Advanced Welding Positions

In addition to the four basic welding positions described above (which primarily address plate welding positions encountered in structural steel welding), there are more advanced positions commonly found in more specialized applications in the welding industry, such as in process piping.

2G Position

In the 2G position, the pipe is positioned on the vertical plane, with the weld joint on the horizontal axis. The welder starts from one side of the pipe and proceeds in a sideways motion to complete the weld.

5G Position

In the 5G position, the pipe is on the horizontal plane, similar to the 1G position. The difference is the pipe is fixed in this position and does not move or rotate throughout the welding process.

6G and 6GR Positions

6G position welding is when the pipe is set in the fixed position on a 45-degree angle. The 6G position is the most challenging weld to perform, requiring high levels of skill and dexterity. The welder must be able to weld the pipe in all positions within the weld joint, without rotating the pipes.

Welders use the “R” in the 6GR designation to signify the use of a restriction. This means they place some sort of restricting ring near and off to one side of the weld joint. This forces the welder to make the weld from only one side of the weld joint. (This is commonly found in welding tests for work in refineries or other facilities where it may be necessary to perform welds with limited access.)

Positions for Pipe Welding

Pipe welding may be more challenging due to the fact that the welder may have to weld in all positions within the same joint. For this reason, pipe welding codes contain their own specific designations. It is possible to use both groove welds and fillet welds in pipe welding. As with plate welding positions, these are designated by either “G” or “F” along with the appropriate number.

Horizontal Pipe Rolled Weld

Expressed as 1G in pipe welding, the pipe is placed in rollers, a positioner, or a “roll-out” wheel (as it is commonly referred to in the pipe welding industry). The pipe is then rolled to allow the welder to perform all welding on the top side in the flat position.

Horizontal Pipe Fixed Position Weld

In the 5G position, the pipe itself is on the horizontal axis whereas the weld joint is oriented vertically. At no point in the welding process will the weld move from this “fixed” position. To make a weld in the fixed position, the welder starts on top (in the relatively flat position), moves into the vertical position on the sides, and then welds in the overhead position to complete the weld on the bottom side. (Of course, the above progression is reversed when welding a pipe in the vertical up position.)

In the photo above, a welder is completing a groove weld on a pipe in the 5G position. The pipe is fixed horizontally with the weld joint on the vertical axis. Note the overhead position to complete the weld.

Vertical Pipe Fixed Position Weld

In the 2G pipe position, the pipe is on the vertical axis with the weld joint oriented horizontally. The weld is then made moving from the starting point in a sideways manner until the welder has completed the full circumference of the weld pass.

The photo above shows a welder making a weld in the fixed, 2G position. Note the pipe is in the vertical position whereas the weld joint is oriented horizontally.

Multipass Arc Welding

When welding smaller pieces of metal together, one single weld pass or bead is sufficient to achieve the desired weld size. In joining thicker pieces of metal or when welding “out of position,” it may be necessary to deposit multiple weld beads to fill the designated joint properly and achieve the required weld size. This practice of adding additional passes of weld metal is commonly known as “multipass welding.”

How to Choose the Right Welding Position

There are a number of factors to consider when selecting the right position to perform the required weld. In most cases, it is preferable to weld in the flat position due to the fact that, as previously mentioned, it is easier to make clean welds in the flat position and you can use bigger electrodes, thereby greatly enhancing productivity and efficiency.

It may not, however, always be practical, safe, or even possible to weld in the flat position. Welding on a bridge or a building, for example, involves welding on a structure so large that it would be impossible to perform every weld in the flat position. In welding smaller sections of pipe, it is often advisable to “roll-out” — that is to say, position welds in an apparatus capable of rotating the pipe — and always making the weld in the flat, 1G position. When welding large pipelines or welding in facilities where you may be welding on or tying into existing pipe assemblies, it is impossible to move, let alone rotate the pipe from its fixed position. In these scenarios, it is often necessary for the welder to achieve mastery in welding in all positions to be able to consistently achieve sound, code-quality welds.

Assessing the Job Requirements and Access to the Joint

Many job conditions require performing a weld in less-than-ideal conditions. You may have to weld on a section of pipe that is being tied in for final assembly or in a repair or modification type situation that involves working off a scaffolding, man-lift, or other type elevated work platform to achieve the required weld. When welding on steel-framed buildings, welders often work several stories high, welding steel beam and column connections, either off lifts or while sitting on the beam itself. Careful job planning can keep tough, difficult-to-access welds to a minimum but unforeseen errors and circumstances may result in the need to make repairs in tough-to-access places.

Evaluating Personnel Skills and Welders’ Skill Levels

Welders undergo welding tests in specific positions to determine which positions they are qualified to weld in. Welding positions are one of the most important factors in developing welder qualification tests.

When testing structural steel welders to the AWS D1.1, Structural Welding Code, a plate test given in the 1G, flat position would restrict the welder to the flat position only. A weld given in the 3G position qualifies the welder to weld in the flat (1G), horizontal (2G), and vertical (3G) positions.

When qualifying welders in the pipe industry, the 6G test is often administered for the fact that, with this qualification, the welder is qualified to perform welds in any position. It may not always be necessary, however, to have welders qualified to all positions. In welding cross country pipelines over relatively flat terrain, a 5G qualification (a weld test made with the pipe in the horizontal position and the weld joint in the vertical axis) may be sufficient.

The Welding Process

The welding process to be utilized may be a major determining factor in the weld position to perform the work in. For example, SAW (submerged arc welding) is restricted to flat and limited horizontal applications due to the highly-fluid weld puddle, the molten slag, and the need to maintain a granular flux covering the arc. When welding large sections of pipe, beam, or plate, it is common to place the assembly in a positioner and then position the part such that it is possible to make the weld in the flat position.

In contrast, it is possible to use SMAW, “stick,” and TIG welding in all welding positions.

Joint Configuration

The weld joint configuration often has a significant impact on possible weld position. For example, if one has to cope a beam to be fit and welded into another beam, the welder may have to weld in all positions — flat, horizontal, vertical, and overhead — to complete that specific connection.

Thickness of the Base Material

Oftentimes, the base metal thickness has an impact on weld position. Thick sections of metal absorb and dissipate heat differently than thinner materials. If one is welding a beam with thick, heavy flanges in the overhead position, it might be necessary to perform multiple passes, given the inherent challenges involved with welding in the overhead position as opposed to making the same weld in the flat position, where the welder could use larger electrodes to complete the weld much faster. This often has a direct impact on heat inputs, which may have a significant impact on the strength and quality of the completed weld.

Welding Position Certification

As previously discussed, welding position is a major determining factor in welder qualifications. A welder who qualifies on a piece of pipe in the 6G position is qualified to weld pipe in all positions. A welder performing a plate test in the 3G position is qualified to weld flat vertical and horizontal. A welder needs to complete a separate test to qualify for 4G, overhead welding, as per the AWS Structural Welding Code.

Welding Position Specifications in the Welding Procedure Specification (WPS)

Welding procedures are developed based on the position the welding will be performed in. If a contractor — the party responsible for ensuring the welders are qualified according to the designated codes and standards — knows that welders will be facing fixed, out-of-position welds, it may be necessary to develop procedures and qualification tests to ensure welders are qualified to perform any of the welds they might encounter. If they are to perform welding in a shop with a positioner or cranes that enable them to make every weld in a flat position, a procedure that only qualifies 1G, flat position welding may be sufficient.

Determining the Appropriate Welding Position

If the part to be welded is not in a fixed position and can be safely and practically moved, it is necessary for the welder to determine the optimal position to perform the welding process. Factors to take into consideration include, but are not limited to:

Welding process to be used. Some welding processes are difficult out of position, which may limit the welder to flat and limited horizontal positions.
Welding electrodes. When welding out of position, be sure the designation electrodes are capable of producing sound welds in vertical or overhead position welding.
Joint design. Careful consideration of welding positions is advisable when choosing joint designs. Welding a groove weld in a beam splice, for example, may be easier to perform in the flat position.

Adjusting the Welding Position to Optimize Weld Quality

You should carefully consider welding positions to optimize the quality of the weld. If it is possible to position the part to be welded such that the weld is in the flat position, you will be able to increase weld quality and production. When all welding is in the flat position, you can employ more beginner level welders and use larger electrodes, which increases deposition rates and, therefore, productivity.

Safety Measures for Different Welding Positions

The inherent safety hazards associated with welding operations mean you should observe specific safety measures to ensure the health and well-being of the welder.

Safety Gear and Equipment

Safety gear in welding operations should include the following:

Safety glasses
Welding helmet with the appropriate rated lens
Gloves
Clothing of a sturdy, durable material like denim or heavy cotton cloth that protects and fully covers the skin. (Avoid polyester and synthetic materials. Many of these can melt to the skin, causing serious injury if a portion of the weld puddle falls from the weld joint and lands on the clothing.)
Sturdy leather work boots.

Proper Handling of Welding Tools

You should always use welding tools properly and maintain them in good, working order. Check cords and cables to ensure there are no exposed wires that could lead to electrical shock. Grinders should have the handles and guards in place to keep the operator safe.

Flat Position Safety Risks

Welding in the flat position may be the safest, but you should take care to ensure the weld piece is secure on the stands or in the positioner (if applicable) to ensure the piece cannot fall during welding operations, which would result in serious injury.

Horizontal Position Safety Risks

When welding a piece in the horizontal position, there is often a tendency to brace and steady oneself by placing the arm against the part to be welded. Take care to protect the arm from burns from sparks, weld metal, slag, and any residual heat in the workpiece. Pipeline welders commonly use sturdy leather arm guards for this reason.

Vertical Position Safety Risks

When welding in the vertical position, sparks and even molten metal from the weld puddle can fall out and land on sleeves, creases in pants, or footwear. For this reason, heavy duty welding shirts made from cotton or a denim-type material and durable jeans or work pants are a must. Welders should use leather sleeves, jackets, or even chaps for welding processes that generate a lot of heat and/or sparks. Metatarsal guards are effective at keeping sparks from entering boots.

Overhead Position Safety Risks

In overhead welding, there are a few hazards to consider. A welder looking up at the weld puddle may leave the neck exposed, which could result in a sunburn from the UV rays produced by the welding arc. The welder should consider the addition of a helmet bib that clips onto the bottom portion of the hood to help counter this effect.

When welding overhead with a welding process that produces a lot of sparks, welding caps to protect the head are a must. A welding jacket with a high, snug-fitting collar will protect the neck area from burns from welding sparks, slag, or molten metal.

Tips to Improve Your Welding Position Skills

Improving your ability to weld in all positions requires patience, commitment, practice, and strict attention to detail. A number of factors contribute to success in welding in all positions:

Body positioning. Get into a position that allows you to make the weld with minimal strain.
Workpiece positioning. Secure the workpiece to eliminate movement during welding.
Visibility and lighting. Make sure you can see the entirety of the weld joint and any potential hazards in the work area.
Amps and volts. Adjust welding machine settings as necessary to obtain the optimal weld profile.
Travel speed. Finding the ideal travel speed is crucial in achieving sound welds.
Work angle and travel angle. Learning to adjust the travel angle and work angle (the angle of the electrode relative to the weld joint) will help you make good-quality welds on a consistent basis.

Importance of Regular Practice

To master any craft, it is necessary to practice to attain the consistency necessary to produce quality welds in all positions. It is important to analyze every weld you produce. Be honest with yourself when examining the weld. Take note of what you did properly and identify things you could improve. Learn to make every weld better than the last to master the art of welding!

Participating in Welding Workshops and Investing in Continuous Learning

Seek out the advice of more experienced welders. Most veteran craftsmen are usually happy to share tips and tricks to those who express interest. Oftentimes, just a couple tips can make a big difference! Night classes with qualified instructors offer good opportunities for beginner and even novice welders to improve skills. Many welding distributors also offer classes on the evenings and weekends.

Troubleshooting Common Issues in Various Welding Positions

Certain weld defects can occur in almost any welding position. Welding in more difficult positions adds to the likelihood of weld defects.

Dealing with Poor Weld Penetration

When you observe poor weld penetration, evaluate the joint preparation. Is the gap set properly? Is the root face excessive?

If the weld joint has been properly performed and poor penetration is still occurring, check the welding parameters. Inadequate amps and volts at the arc may lead to penetration issues. Excessive travel speed may also result in poor weld penetration.

Resolving Incomplete Fusion

Incomplete fusion is often due to inadequate amps and volts in the welding arc. If you observe incomplete fusion, check and adjust the machine settings, increasing the heat, as necessary. Work angle (the angle of the electrode relative to the workpiece) may be a factor in fusion defects. Confirm the angle at which the molten weld is deposited is adequate to fuse the base metal, filler metal, and other weld passes.

Common Welding Position Defects

There are some common defects that result from welding in specific positions.

Flat Position Defects

Welding in the flat position is often advantageous because it allows for welding with more heat than may be possible in other positions. However, excessive heat can result in burn-through defects. Travel speed should always be adequate to prevent burning through. Traveling too slowly will result in too much heat in one area, which increases the chances of burn through.

Horizontal Position Defects

To control the weld puddle in horizontal welding, you must use the correct work angle to keep the molten weld puddle in place and allow it to solidify into a weld with the proper profile. Excessive work angle combined with too little heat in the weld may lead to fusion defects. You should adjust the work angle to maintain a uniform, consistent weld with the proper profile.

Vertical Position Defects

Welding in the vertical position takes the right combination of amps and volts, arc length, travel speed, and travel angle to obtain the proper weld profile. Welding too hot and slowly will result in too much metal in the molten state, which may either fall out of the joint or result in a poor weld profile.

Undercut often appears in welds made in the vertical position. It usually is the result of welding too hot or poor technique. Excessive heat results in the molten weld metal falling back out of the joint. It is crucial to find the right combination of heat, travel speed, and technique to make sound welds in the vertical position.