Welding Positions are basically the different angles of joining metals. Normally, there are four types of welding positions namely horizontal, flat, vertical, and overhead. And the most common types of welds are groove and fillet welds. Welders can perform these two welds in all four positions. Besides this, there are special letters to designate fillet and groove welds.
Fillet Weld (F) – It is a welding method for combining two parts of metal vertically or slightly at an angle.
Groove Weld (G) – It is a weld made in the groove. It requires full penetration for laying strong welds.
Grove and Fillet Welding Positions
Normally, the following numbers and letters are used.
For groove welding positions-
- 1G – (flat welding position)
- 2G – (horizontal welding position)
- 3G – (vertical welding position)
- 4G – (welding position overhead or overhead)
- 5G – (uphill/downhill vertical welding position)
- 6G/6GR – (overhead vertical welding position)
For fillet welding positions-
- 1F – (flat welding position)
- 2F – (horizontal welding position)
- 3F – (vertical welding position)
- 4F – (welding position overhead or overhead)
Types of Welding Positions by AWS and ASME
- 1G/1F
- 2F/2G
- 3G Uphill
- 3G Downhill
- 4F/4G
- 5G Uphill
- 5G Downhill
- 6G Uphill
- 6G Downhill
Pipe and Plate Weld Joint Positions
Normally there are six welding positions with certain numbers and letter i.e. 1G, 2G, 3G, 4G, 5G, and 6G/6GR. All the positions are used in various angles and shapes while performing welding. Generally, the ways and ideas of welding are similar in different countries. But the AWS D1.1 (referring to AWS A3.0), ASME IX, and ISO 15614-1 use different names in their Tables.
1G/1F/PA Position (Flat)
1G/1F/PA position is a flat welding position. In this weld position, welders put metal piece right below the torch. This position is performed for butt, groove and fillet welds as well.
2G/PC Position (Horizontal)
This is a horizontal position for butt welds. In this welding position, the metal piece remains parallel to welder’s body and he welds it while remaining in front of him.
2F(2f)/PB Position (Horizontal)
2F/PB Position is a horizontal welding position used for fillet welds. It is harder than the 1F position. A welder needs to hold the torch at a 45° angle most of the time with the piece next to him. But the exact angle of torch depends on the angles of the plate and pipe.
In the 2F/2f position, the butt weld is a bit more difficult than flat welding. This happens due to the molted metal flowing downward of the joint and the torch heat rises upward of the joint. Consequently, a uniform deposit cannot be applied to joints.
For better welds, welders need to align the metals and weld at both ends. The movements of the torch should be slightly up and down for spreading equal heat to both sides of the joint. In this way, the molten metal will not flow the lower side of the joint and solidify the weld metal faster. For master, a welder needs a lot of experience in 2f or any horizontal position. 2f is one of the horizontal positions for the fillet test.
There is another horizontal fixed weld position or pipe welding position. In this, the pipe axis remains nearly horizontal. It is noteworthy that the pipe being welded should not move or rotate while performing welding.
In another horizontal rolled welding position, pipe puts flat and welding is done on by rotating it as required. First, the welder needs to align the joints and weld it. For gripping pipe, welders can use steel made bridge clamps while using a welding torch.
Another similar welding position is 2G, which means a horizontal welding position for groove not for fillet welds. In this position, the weld axis remains horizontal and the weld is facing the vertical plane.
3G Uphill/PF Position (Vertical)
It is a vertical-up position used for both butt and fillet welds. While welding, the angle of the torch remains at 45°, and welder used the metal from the lower part.
3G Downhill/PG Position (Vertical)
It is a vertical-down position used for fillet and butt welds. Welders used the metal from the upper part. This position is considered good in terms of productivity.
4G/PE Position (Overhead)
It is an overhead position used for butt welds. Welders need to hold the torch from below the metal piece. Normally, it is a complex and hard position. Welders must set proper parameters before welding.
4F/PD Position (Overhead)
This is also an overhead position used for fillet welds. Mostly, welder holds the torch at a 45° angle while being below the metal piece and it depends on the pipe/plate positions.
5G Welding Positions-
5G welding position is used for pipe welding and the axis of the pipe is stable in a horizontal position without turning or rotating. 5G stands for ‘groove weld’. The American Welding Society/The American Society of Mechanical Engineers names it as 5G; and that of ISO/EN standards as PF.
5G Uphill Position (Vertical)
It is a vertical-upward position used for pipe butt welds. It is a common manual way of pipe welds. In this position, welders follow three ways of welding in sequence starting from overhead position to horizontal and then the flat position. In the 5G position, the pipe is not turned or rotated; that is why it is difficult.
5G Downhill Position (Vertical)
It is a vertical-downward position used for pipe butt welds. 5G downhill position is a very good and productive way of welding pipes manually. In this position, welders should use proper and specific equipment for welding pipes against the dragging force of gravity of molten metal. By doing so, welding productivity is increased, and imparts desired welding results. During 5G, welders go through three welding stages starting from flat position, then horizontal position and ending with the overhead position.
Different names of 5G welding position by the following bodies:
ASME/AWS Nomenclatures | ISO Standard Positions |
5G Uphill welding position | PH welding position |
5G Downhill welding position | PJ welding position |
6G Welding Positions-
This is one of the hardest types of welding positions for welders to perform. The position is a pre-condition for getting certified. To some extent, this position is similar to 5G/PH/PJ but the pipe stands at 45° to the other one. Other names are 6G Uphill/H-L045 and 6G Downhill/J-L045 Position.
6G welding position also known as overhead weld position or welder certification test position. In this position, one pipe needs to position at a 45° angle to the other one. That’s why it becomes the most complex and challenging position for welders. Further, welders need to make so many body positions while performing welding.
While 6G position welding, there are mainly three welds i.e. horizontal (difficult), flat (easy), and vertical welds (demanding). Filling metal flow downwards is the main cause of the difficulty. And in a vertical position, it becomes more difficult for welders as it is overhead welding. Therefore, a welder needs a lot of practice in a 6G position before going for the actual weld. A certified welder rarely faces a 6G position while working in industry during their service, but it is a common pre-employment test for them.
The main use of a 6G weld position is for fabrication and installation of pipe and pipelines mostly in chemical plants, oil and gas plants, industrial plants, and any other similar industry using pipe and pipelines.
6GR Test
It is another form of a 6G test. The letter R stands for ‘restricted’. It means the weld is performed in a “ring mode” by placing a steel plate below the weld site with an inch gap. Basically, this is another difficulty level for welders in the certification process. In 6GR, welders need to make joints near to impediments like brackets, walls and attaching pipe to another structure.
Conclusion
Thus, the information on types of welding positions like 1G, 2G, 3G, 4G, 5G, and 6G/6GR is beneficial for students, welders, educators, and other professionals. Welding positions play the main role in the certification process for welders. They may be tested for positions starting from 1G to 6G both for the fillet and groove welds.
Source: https://www.weldinginfo.org/welding-processes/types-of-welding-positions-and-joins/