HOW TO: Weld Vertically

Welding in any industrial setting, you are likely to need to weld vertical from time to time. Heavy machinery or other parts needing to be joined can be impossible to manoeuvre into a horizontal welding position and it is much more time effective for the employer to simply require welders to be proficient in upright welding, although this demands a high level of skill and experience. Depending on this skill level and a range of other factors, you will either decide to weld vertical-up or vertical-down.

When welding vertical-up, you begin at the bottom of the piece and slowly work your way up. Therefore, each weld bead forms a base or “shelf” for the one above. A good rule of thumb is to make each shelf 1.5 to 2 times wider than the electrode you are using; this means that the puddle you create will freeze in the time you take to make the next shelf. A popular method is to use a zigzag or weaving technique. By focusing on the sides of the join, the weld pool in the centre will have time to cool enough to prevent burn through. It should also save your feet from dripping molten metal. Additionally, be sure to hold the electrode slightly uphill and stick closer to the surface as it will help to achieve a better penetration by a more direct and shorter arc.

Vertical-down, therefore, is the reverse. You begin at the top, working against gravity as it brings the molten puddle into your work zone. To weld vertical-down, it is important to stay ahead of the slag at all times, meaning you cannot pause as you would with vertical-up, as the slag will then begin to invade your current work area. Using a quick-freezing rod, like those mentioned below, will help to prevent this to some degree. You will also need to set the amperage on your machine carefully to avoid burn through.

TIG welding is extremely popular for its versatility and the fact that it produces no slag. There are three main methods for vertically TIG welding. The keyhole method gives great weld penetration and forms strong joins. The method involves heating the two pieces until a gap forms in the middle and then a filler metal can be used to fill the gap. The up and down method is another way to apply filler metal, the molten pool travels and is adjusted as it goes. Lastly, the stitch method involves moving the torch side to side and up, distributing heat evenly to the metal plates. As with all TIG welding, so long as you maintain the heat input you can have incredible control over the weld bead which will lead to very pleasing looking welds.

Having said this, the most commonly used process for vertical welds is stick or MMA welding. This process is particularly useful outside where wind could blow away shielding gas used in other processes.

There are a number of tricks that can help you achieve better welds more efficiently when stick welding vertically, the first being choosing the correct electrode. Typically, for welding vertically up, chose a low iron powder content as iron powder takes longer to cool and you want your welds to cool as quickly as possible to avoid dripping. sifTRODE 6010 and 7018 are both good options which can be used with the whipping or stacking method for the former (whereby you pull the stick in and out of the weld pool as you go) and the weaving technique for the latter. When welding vertically down, a sifTRODE 7024 can be used as it sets a little less quickly, allowing the weld pool to travel down the join as you work.

Though welding vertically up can be tricky and more time consuming, it does produce better results, which is why we would recommend it over vertically down – unless you are working with very thin metal structures.

Lastly, by lowering the current and amperage, to slow down the entire process, you can reduce the weld pool size and increase your control, be sure to allow the molten puddle to freeze off each time before continuing.?