What Are 1G, 2G, 3G, 4G, 5G and 6G Welding Positions?
A practical guide to plate and pipe groove-weld test positions—what each code means, how gravity and access change the weld, how AWS and ISO terminology differ, and what the designations do and do not prove about welder qualification.
For common U.S. groove-weld qualification terminology, 1G is flat, 2G is horizontal, 3G is vertical and 4G is overhead on plate. Pipe tests add rolled 1G, fixed vertical-axis 2G, fixed horizontal-axis 5G and fixed 45-degree 6G. “G” means groove weld—not a universal production-position label.
Plate + pipe positions
Process, material, thickness, diameter, progression, backing and the governing code still determine the qualification range.
Image: Newfoundlandguy, Wikimedia Commons, CC BY-SA 4.0.The six codes at a glance
These labels are best understood as qualification-test configurations. Plate commonly uses 1G through 4G. Pipe adds fixed configurations such as 5G and 6G, while 1G and 2G can also describe pipe tests with different axis and rotation conditions.
Weld deposited from above; on pipe, the coupon may rotate.
Plate is vertical; fixed pipe commonly has a vertical axis.
Weld progresses upward or downward on a vertical plate.
The joint is above the welder and the weld is made from below.
The pipe does not rotate; the welder travels around it.
The inclined pipe stays fixed, combining changing access and gravity.
What the number and “G” actually mean
The number identifies the orientation of the qualification coupon and joint during the test. The letter “G” means groove weld. It distinguishes these tests from fillet-weld tests, which use “F” designations such as 1F, 2F, 3F and 4F. A 3G plate test and a 3F fillet test are therefore not interchangeable labels.
A crucial distinction is often lost in simplified welding-position charts: AWS uses 1G, 2G, 3G and 4G as test-position designations. In production, the actual weld is normally described as flat, horizontal, vertical or overhead. That wording matters when a drawing, welding procedure specification, welder performance qualification or inspection record is being prepared.
Position is only one variable
A position code does not tell you the welding process, joint detail, base material, filler metal, thickness, pipe diameter, direction of vertical progression, use of backing, shielding arrangement or acceptance criteria. Two welders can both be tested in 6G and still have different qualification ranges because the governing code and essential variables differ.
The controlled orientation of a coupon used to demonstrate welder or procedure capability under a governing qualification standard.
The actual orientation encountered on the component: flat, horizontal, vertical, overhead or a changing combination around pipe.
The direction a vertical weld is deposited—commonly vertical-up or vertical-down. Coverage and technique can change with progression.
Whether the pipe can turn during welding. Rolled 1G pipe is fundamentally different from a fixed 5G or 6G coupon.
1G through 4G: the plate positions
Plate tests isolate four basic relationships between the joint, gravity and the welder. Training normally begins flat, then adds horizontal, vertical and overhead control. The exact parameter window must still come from the approved procedure.
Flat plate groove
The plate is essentially horizontal and the weld is made from above. Gravity supports the pool, visibility is usually good and deposition can be efficient.
- Common starting position for skill development
- Useful for learning arc length, travel and puddle reading
- Do not assume a 1G pass qualifies other positions
Horizontal plate groove
The plate is vertical and the groove axis is horizontal. Gravity pulls liquid metal toward the lower sidewall, making bead placement and sidewall fusion important.
- Watch upper-side undercut and lower-side overlap
- Electrode or torch angle helps support the pool
- Joint geometry must match the test specification
Vertical plate groove
The weld progresses vertically. Vertical-up and vertical-down are distinct techniques and may not provide the same qualification coverage.
- Vertical-up often favors penetration on thicker work
- Vertical-down may be used for suitable thin-material procedures
- Heat input and pool size require close control
Overhead plate groove
The joint is above the welder and the weld is made from below. Gravity, exposure to sparks and constrained body position make technique and PPE especially important.
- Use only procedure-approved settings and consumables
- Maintain a controllable pool rather than chasing speed
- Plan access, cable routing and safe escape space
1G–6G welding position chart
This chart separates coupon setup from the practical welding challenge. It is a planning aid, not a substitute for the position diagrams and qualification tables in the applicable code.
| Designation | Typical test coupon | Orientation / rotation | Gravity exposure | Common training focus | Important caution |
|---|---|---|---|---|---|
| 1G plate | Grooved plate | Plate flat; weld from above | Mostly supports the pool | Travel consistency, angle and fusion | Flat qualification does not automatically cover out-of-position work. |
| 1G pipe | Grooved pipe | Pipe axis horizontal; coupon may rotate | Welding point can remain near the top | Root consistency with controlled rotation | Rolled production is not equivalent to fixed pipe welding. |
| 2G plate | Grooved plate | Plate vertical; weld axis horizontal | Pool tends toward lower sidewall | Sidewall fusion and bead placement | Do not confuse plate 2G with pipe 2G geometry. |
| 2G pipe | Grooved pipe | Pipe fixed with vertical axis | Joint remains horizontal around circumference | Consistent torch position around fixed pipe | Use the governing standard's exact test arrangement. |
| 3G plate | Grooved plate | Plate vertical; weld progresses up or down | Pool tends to sag | Heat control, progression and tie-in | Vertical-up and vertical-down may qualify differently. |
| 4G plate | Grooved plate | Joint overhead; weld from below | Pool is pulled away from joint | Pool size, access and operator stability | Ergonomics and protection from falling spatter are critical. |
| 5G pipe | Grooved pipe | Horizontal axis; pipe fixed | Changes continuously around pipe | Transitions through flat, vertical and overhead regions | The welder moves; the coupon does not rotate. |
| 6G pipe | Grooved pipe | Pipe fixed at approximately 45° | Changes with position and access | Body control, visibility, transitions and root integrity | Broad coverage is code-dependent, not automatic. |
Always use the edition of the qualification code cited by the contract. Position diagrams, ranges and essential variables may differ between standards and applications.
At the top, side and underside of the pipe, gravity, sightline, hand position and shielding all change.
Image: Vronmikah2024, Wikimedia Commons, CC0 1.0Why 5G and 6G feel different from plate
A pipe joint wraps around a curved surface. When the coupon is fixed, the welder must adapt continuously instead of repositioning the work. The root opening, land, tack placement and fit-up must remain consistent around the circumference, because small local variations can become incomplete fusion, excessive penetration or an irregular root.
Rolled pipe
The pipe axis is horizontal and the coupon rotates. The weld point can remain near the top, making this the pipe configuration most comparable to flat welding. Rotation speed and synchronization become process variables.
Fixed vertical-axis pipe
The pipe stands with its axis vertical and does not rotate during the qualification test. The groove runs horizontally around the pipe, requiring consistent travel and orientation around the circumference.
Fixed horizontal-axis pipe
The operator progresses around the pipe and encounters effective flat, vertical and overhead regions. Starts, stops and quadrant transitions must be planned to meet the procedure and examination requirements.
Fixed pipe inclined at 45°
The 45-degree axis removes the simple symmetry of 5G and creates demanding access and body-position changes. It is widely treated as an advanced pipe qualification test—but its coverage still follows the code.
Gravity, access and technique—not just the label
As the joint moves out of the flat position, the welder must manage a pool that no longer sits naturally in the joint. The correct response depends on the process, consumable classification, transfer mode, joint and approved WPS.
Molten-pool behavior
Gravity can pull the pool toward a lower sidewall, down a vertical joint or away from an overhead root. Pool size, arc placement, wire delivery and travel pattern must keep both sidewalls fused without creating undercut or overlap.
Watch: toe fusion, root profile, saggingHeat input and travel
There is no universal rule that every overhead weld must simply be slower or lower power. The acceptable window comes from the procedure. Excessive heat can enlarge the pool; insufficient energy can reduce fusion.
Use: qualified settings, not a generic multiplierFiller and electrode control
Torch angle, electrode manipulation and filler placement help direct energy and support the pool. What works for SMAW may not translate directly to GTAW, GMAW, FCAW or handheld laser welding.
Confirm: process-specific techniqueShielding stability
Gas coverage can be affected by nozzle angle, distance, drafts and access around the joint. Pipe roots may also require internal purge control. A visually clean surface does not prove adequate shielding or root quality.
Control: gas delivery and environmentStarts, stops and transitions
Fixed pipe requires planned tie-ins between segments or operators. Arc starts, crater treatment and restart overlap must comply with the WPS and inspection requirements rather than being improvised during the test.
Plan: quadrants and tie-in locationsErgonomics and line of sight
A welder who cannot see the leading edge or hold a stable body position will struggle to repeat the procedure. Fixtures, access platforms, cable routing and lighting influence quality as directly as hand skill.
Engineer: access before testingAWS-style 1G–6G and ISO 6947 are not the same naming system
Both systems describe welding orientation, but they do not use identical labels or qualification logic. Copying a position code from one standard into documents governed by another can create an avoidable technical mismatch.
Common U.S. designations
AWS and other U.S.-based code contexts commonly use numeric-plus-letter test designations such as 1G through 6G. AWS educational guidance emphasizes that 1G–4G are test positions, while production welds are described as flat, horizontal, vertical and overhead.
- “G” identifies a groove-weld test.
- “F” identifies a fillet-weld test.
- Pipe setup includes axis orientation and whether the coupon is fixed or rolled.
- Qualification range is read from the governing code tables.
ISO 6947 position designations
ISO 6947:2019 defines welding positions for testing and production across butt and fillet welds and different product forms. It uses letter combinations such as PA, PB, PC, PF and PG rather than simply adopting 1G–6G.
- ISO 6947 includes position limits and an annex comparing ISO and U.S. systems.
- A comparison table is not permission to assume every qualification is equivalent.
- Use the standard and edition specified by the contract.
- Keep drawings, WPS/PQR records and welder certificates internally consistent.
Does 6G qualify a welder for every position?
6G is widely regarded as an advanced pipe test because the fixed 45-degree coupon forces the welder through changing orientations and access. AWS training material notes that it commonly provides broad pipe-position coverage. But “6G qualifies everything” is an unsafe shortcut.
The certificate's usable range is determined by the applicable code and the variables recorded during the test. A welder may have broad position coverage and still be outside qualification because the production joint uses a different process, product form, pipe diameter, deposit thickness, base-metal group, filler classification, backing condition or vertical progression.
Check these variables before assigning production work
- Governing code, edition and project specification
- Welder performance qualification versus procedure qualification
- Welding process or combination of processes used during the test
- Plate versus pipe, plus pipe outside diameter and wall thickness ranges
- Base-metal and filler-metal grouping required by the code
- Use or removal of backing and root technique
- Vertical-up or vertical-down progression where applicable
- Position range permitted by the specific qualification table
- Examination method, acceptance criteria and continuity requirements
Likewise, combining plate tests can produce broader coverage in some code contexts—for example, certain 3G and 4G combinations—but the permitted range must be taken from that code rather than generalized across structural steel, pressure piping, pipelines and other applications.
How welding position applies to laser welding
The 1G–6G vocabulary originated in conventional fusion-welding qualification practice and should not be treated as a complete handheld or robotic laser procedure. Nevertheless, orientation still changes melt-pool behavior, shielding, wire delivery, access and operator safety.
For a handheld laser welder, the practical question is not only whether the seam is “vertical” or “overhead.” It is whether the head can maintain the required stand-off and angle, whether the wire enters the leading edge consistently, whether shielding reaches the active pool, and whether reflections, plume and spatter are controlled throughout the motion.
Melt-pool stability
Out-of-position seams may narrow the usable power, speed, wobble and focus window. Validate penetration and fusion across the actual orientation.
Wire delivery
Gravity and access can move filler wire away from the intended leading edge. Gun, feeder, liner and fixture geometry must work together.
Shielding and plume
Nozzle orientation, gas flow, extraction and part geometry affect coverage. Overhead work also changes the path of hot particles and fume.
Automation feasibility
A position that is awkward manually may be consistent with a positioner, seam-tracking system or robot—provided reach, collision and cable limits are modeled.
Qualification plan
The applicable product code and customer specification determine whether and how the laser process, procedure and operator must be qualified.
Can every welding process be used in every position?
No. Position capability depends on the process variant, consumable classification, transfer mode, equipment and qualified procedure. Treat broad statements such as “TIG works in all positions” as a starting point, not a production authorization.
| Process family | Position potential | Practical strengths | Typical limitations to verify |
|---|---|---|---|
| SMAW | Many consumables support all-position work, but classification matters. | Portable and tolerant of field access; widely used for pipe qualification training. | Electrode designation, progression, slag control, moisture control and WPS amperage range. |
| GTAW / TIG | Can be applied in many positions with suitable procedure and access. | Precise root control and high-quality pipe roots. | Shielding sensitivity, travel speed, operator coordination, purge quality and deposition rate. |
| GMAW / MIG | Position range depends strongly on transfer mode, wire and procedure. | High productivity and automation potential. | Spray transfer is not automatically suitable for all positions; pool size, wire feed and shielding require control. |
| FCAW | Many wires are designed for all-position work; classification must be checked. | Productive structural and field welding with suitable consumables. | Slag system, wire classification, polarity, fume extraction and vertical technique. |
| SAW | Most commonly flat and suitable horizontal configurations. | High deposition and consistent mechanized production. | Granular flux retention, joint orientation, equipment access and procedure-specific position limits. |
| Laser welding | Possible in multiple orientations with validated optics, shielding, motion and safety. | High speed, low distortion and automation potential. | Reflectivity, fit-up, wire delivery, keyhole stability, beam safety and code/customer qualification requirements. |
A practical training progression
Training often moves from simple pool control to changing gravity and access. The sequence below is useful for planning practice, but the formal test sequence and acceptance criteria must come from the relevant program or code.
Build a repeatable flat baseline
Use 1G plate to learn joint preparation, tack placement, machine setup, arc or beam positioning, travel consistency and basic visual inspection.
Add horizontal and vertical control
Move to 2G and 3G while recording how pool shape, sidewall fusion and travel respond. Train vertical-up or vertical-down only within the intended procedure.
Introduce overhead safely
Before 4G, verify PPE, booth clearance, cable management and protection from falling hot material. Develop stable body position before pursuing speed.
Transfer fundamentals to pipe
Practice rolled pipe, then fixed 2G or 5G to learn circumference control, quadrants, tie-ins and changes in visibility.
Attempt 6G after process control is stable
The inclined fixed coupon combines the previous demands. Use standardized fit-up and inspection so defects lead to a specific corrective action.
Validate against production reality
After passing a test, rehearse the actual joint, access restriction, fixture, material and WPS. Qualification establishes permission; production readiness requires repeatability.
Harder access increases both quality and safety risk
Overhead and fixed-pipe work place the welder closer to hot metal, sparks, fume and awkward postures. Safety controls must be designed for the actual position, enclosure and process—not copied from a flat training coupon.
Eye, face and body protection
Use the correct helmet or laser-rated protective system, safety glasses, gloves, fire-resistant clothing and footwear for the process. Protect exposed areas from radiation, sparks and hot metal.
Inspect PPE before every shiftVentilation and source capture
Welding fume should be controlled with ventilation and local exhaust positioned as close as practicable without disturbing shielding. Coatings and base-metal composition can change the hazard.
Evaluate the actual contaminantConfined-space controls
Pipe, vessel and tank work may create confined or enclosed spaces. Follow entry, atmospheric testing, ventilation, attendant and emergency procedures required by the site and regulations.
Never improvise confined-space entrySecure the workpiece
A qualification coupon, pipe spool or positioner must be restrained against unintended movement. Rotation systems need guarded controls, emergency stops and a verified load rating.
Fixture before striking an arcPlan body position
Overhead and 6G work can fatigue shoulders, wrists and the lower back. Provide stable platforms, clear footing, suitable lighting and breaks before precision declines.
Ergonomics supports weld consistencyControl nearby hazards
Remove combustibles, screen adjacent personnel and control cables, hoses and hot work. Laser welding additionally requires a controlled area, interlocks and wavelength-specific protection.
Use a process-specific hot-work planRelated welding pages and next steps
Position is only one part of a successful welding project. Use these pages to connect orientation with equipment, pipe applications, process planning and physical sample validation.
Handheld Laser Welding Machine
Explore portable laser-welding configurations for sheet, tube and fabricated assemblies.
View laser welders → ApplicationPipe Laser Welding
Review the factors that affect speed, seam access, shielding and fit-up on pipe joints.
Explore the application → SolutionPipe & Tube Welding Solution
Connect workpiece geometry and production goals with a practical system direction.
Review the solution → ValidationSample Testing
Verify access, parameters, bead quality and production cycle time on your actual joint.
Plan a sample test →1G–6G welding position FAQ
Concise answers to common training, qualification and production questions.
What does “G” mean in 1G or 6G?
“G” means groove weld. The test uses a prepared groove between the pieces. Fillet-weld test positions use “F,” so 2G and 2F refer to different joint and test configurations.
What are the 1G, 2G, 3G and 4G plate positions?
In common U.S. test terminology, 1G is flat plate, 2G is a horizontal groove on a vertical plate, 3G is vertical plate and 4G is overhead plate. Production welds are usually described as flat, horizontal, vertical or overhead rather than by the test code alone.
What is the difference between 5G and 6G pipe welding?
Both use fixed pipe. In 5G the pipe axis is horizontal; in 6G the axis is inclined approximately 45 degrees. The 6G setup combines changing gravity, access and body position around an inclined coupon.
Can the pipe rotate in 5G or 6G?
No. The pipe is fixed during 5G and 6G qualification tests. A pipe that rotates with its axis horizontal is commonly associated with a rolled 1G pipe configuration.
Is 6G the hardest welding position?
6G is widely regarded as one of the most demanding common pipe qualification tests because the fixed 45-degree coupon requires changing technique and access. Actual difficulty still depends on process, material, thickness, joint and restriction.
Does passing 6G qualify a welder for every position?
Not automatically. 6G often gives broad positional coverage, but the governing code determines the qualified process, position, product form, diameter, thickness, material, backing, progression and other ranges. Review the original qualification record against the production WPS.
Which welding position should a beginner learn first?
1G flat plate is a common starting point because visibility is good and gravity supports the pool. A sound program should still teach joint preparation, safety, parameter control and inspection rather than focusing only on bead appearance.
Is 2G the same for plate and pipe?
No. A 2G plate test uses a vertical plate with a horizontal groove. A common 2G pipe groove test uses fixed pipe with its axis vertical. Always consult the position diagram in the governing standard.
What is the difference between 3G vertical-up and vertical-down?
They use opposite progression directions and different pool-control strategies. Qualification coverage and permitted production use can differ, so the direction must be recorded and matched to the code and WPS.
Does ISO use 1G, 2G, 3G and 4G?
ISO 6947 uses its own letter-based welding-position designations and includes a comparison with U.S. designations. Do not assume the systems are identical or that qualification automatically transfers between them.
Can laser welding be performed in 3G, 4G, 5G or 6G orientations?
Laser welding can be engineered for multiple orientations, but the suitable power, speed, wobble, focus, shielding, wire delivery, fixture and safety controls must be validated on the real joint. The applicable code or customer requirement determines the qualification route.
What information is needed before choosing a qualification test?
Identify the governing code and edition, product form, material, thickness, pipe diameter, joint, process, filler, backing, progression, intended production positions, examination method and customer requirements. Then select the test that gives the required—not merely the broadest—coverage.
Standards and reference sources
- American Welding Society — “The Answer Is”. Explains the distinction between 1G–4G test positions and flat, horizontal, vertical and overhead production positions.
- American Welding Society — How to Pass a Welding Test. Describes common plate and pipe training progression and the fixed 45-degree 6G test.
- AWS QC7 Supplement F. Provides piping qualification position and test-condition examples, including fixed 2G and 5G pipe configurations.
- ISO 6947:2019 — Welding and allied processes — Welding positions. Defines ISO welding positions and includes comparison information for U.S. designations.
- TWI — What Is Pipe Welding?. Background on pipe-welding applications, processes and position terminology.
- OSHA 29 CFR 1910.252 and 29 CFR 1926.353. General welding protection and ventilation requirements.
Have a difficult pipe, vertical or overhead laser-welding joint?
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