It is important to observe the correct position when welding. In addition, the position of not only the person and the welding machine, but also the electrode, as well as the seam, is important. In other words, the welding technology, which also involves the selection of the correct position, directly depends on the spatial arrangement of the structure that needs to be connected by welding.
Lower position
To date, 4 types of welding positions are known. It can be vertical, horizontal, lower and ceiling.
You can start the review from a low position. Most often, this type is used if a simple structure is being welded, as well as special requirements for quality, strength, etc. are not imposed on the state of the seam. The surfaces that need to be welded together should be in a horizontal position, and the electrode location should be vertical.
Welding in the lower position allows two-sided welding of metal if the maximum thickness of the material does not exceed 0.8 cm. One-sided welding can also be performed, but then the maximum thickness is reduced to 0.4 cm.
Seam quality and welding parameters in the lower position
How high quality is this seam? Whatever method of welding the seam in the lower position is applied, the strength will be quite high. However, several factors will influence the quality of the compound.
- The first factor is the diameter of the electrode used in the welding.
- The second is the thickness of the elements being welded and the presence of a gap between them.
- The magnitude of the welding current will also matter in this case.
However, despite all this, the lower position during welding is considered the most productive and optimal when it is necessary to connect structures using a welding machine.
But nevertheless, the method has a significant drawback, which lies in the fact that there is a risk of a burn-through of the structure. At the moment, specialists in the preparation of the project still try to use just such a position in welding, since it is considered the best. As for the types of connections that can be performed using the lower position, there are two of them:
- The first is welded joints.
- The second is welded joints of the angular type.
Second type
When welding in a horizontal position, it is necessary that the elements to be connected are arranged vertically and the electrode horizontally. The seam in this case should be horizontal.
Some difficulties begin here, since such an arrangement complicates the work of a specialist. In addition, the situation is considered unfavorable for work also because there is a likelihood of molten metal flowing out of the weld pool. In this case, the metal can get on the edge of the material, which is located below. Because of this, it is necessary to make an oblique undercut of the edge above, and leave the lower part unchanged before proceeding with the welding itself. This action will help to avoid marriage, which can occur in the event that the metal flows out, since then you will have to cut the top layer of the weld.
To summarize, we can say that such a position during welding can also be used without problems if the edges are correctly processed in advance, and the specialist will have experience in carrying out just this type of work.
Third type of position
When working in an upright position, the electrode should be horizontal and the working surface vertical. The position of the seam during welding in this case will remain vertical. The same problem is present here as in the previous case. Drops of molten metal will tend to fall down due to gravity. Therefore, without special surface preparation, the probability of marriage is very high.
Recommendations for welding
There are several points that must be taken into account if it is necessary to weld in an upright position.
- Welding can only be done with a short arc. Only in this case can such an effect be achieved in which metal penetrates into the crater of the weld.
- This position during welding forces to use only those electrodes that are characterized by increased viscosity of the weld pool in order to minimize the flow of metal melt.
- The welding process can only be performed top-down or bottom-up. If you use the first method, you can significantly increase productivity, but it will inevitably worsen the quality of the seam. If you apply the second method, then everything will be the other way around, the quality of the seam will increase, but productivity will be extremely small.
The last type of location. Ceiling mounted
Here it is worth starting with the fact that this type of weld is considered the most difficult to fulfill. Because of this, the highest requirements are placed on the qualifications of the specialist who will fulfill it. Welding in the ceiling position requires the electrode to be positioned vertically, and the elements to be welded are horizontal. As for the seam, it will be at the bottom of the welded edges. In other words, we can say that this is welding, which takes place in the lower position, but is turned upside down by 180 degrees. The greatest risk is that molten metal will flow down completely without getting into the weld pool.
Here, as in the previous case, there are several recommendations that must be necessarily implemented.
- The length of the arc should be as short as possible, as should the current.
- Here it is necessary to use electrodes that are characterized by a small diameter, as well as high refractoriness, so that it is possible to hold melt drops by tension.
- During welding, it is necessary to make a change in the distance between the electrode and the coating, that is, to zoom in or out the welding machine.
It is also worth noting that this method is not used at all if the thickness of the metal is sufficiently small. This is due to the fact that gas bubbles will inevitably appear, which will degrade the quality of the weld. All this led to the fact that such a situation in welding is applied only when other types are not feasible at all from a technical point of view.
Electrode position
In welding, the position of the electrode also plays a very important role. For example, if the work is carried out in the lower position, then the quality of the seam will vary greatly depending on the liquid slag. The correct location of the electrode in this case will allow the welder to control the process of slag extraction, and therefore to regulate the quality of the seam. Currently, there are three main types of arrangement of this element.
The first type is forward at an angle. In this case, liquid slag will form and run forward, which will interfere with the welding process. For this reason, use this option position is only in hard to reach places where other positions of the electrode are excluded.
Another way at an angle back. This method is most often used for welding joints and corners of a structure.
The last option is welding at an angle of 90 degrees. This position will allow to control liquid slag and its distribution. It will follow the weld pool, which will favorably affect the quality of the weld.
Distance
It is worth paying attention to such a thing as the distance between the electrode and the part. It is very important to monitor this parameter, as this will also affect the quality and roughness of the seam. Today it is believed that the optimal arc length is 2-3 mm.
If the electrode is located almost completely against the part, then it is necessary to use only currents with a high and medium value. And the movements should not be oscillatory or transverse type.
There is an option in which the distance from the electrode to the element will be exactly 50% of the numerical value of the diameter of this consumable. Thus, it is possible to significantly reduce the width of the seam, for example. Welding is possible, during which the distance will be 150% of the electrode diameter.