Last Updated on Jan 21, 2023
Weld Beads are actually formed by placing and depositing a thick filler material in a small, medium, or large joint between two pieces of metal. The filler material is melted in a way so that it can easily stick on the joint area. This process is usually done by a special kind of gadget called a torch.
The movement of the torch will determine what kind of beads will form on the joint area. So, be careful when using these torches and make sure that what kind of results you are looking for before doing welding.
What are the uses of different and distinct torch movements?
We can sew our clothes in many different and distinct ways and as we like. There is no limitation to sewing a specific design on a machine. We can design our clothes according to our needs and requirements. The same applies to weld beads. There are many different and distinct ways available for using weld beads. You can use any one of them on pieces of metal to get your desired results.
But unlike tailors, mostly welders need to wear special kinds of gloves, glasses, and face protection to avoid any harm in these areas. A welder needs to perform his work by coming in an awkward position to avoid harms and damages that might result from this procedure.
Role of gravity in welding
Gravity plays a major role in welding. It determines how the molten filler material gets deposited in between pipes and metal plates or pieces. For example, you need to use your hand fast and do your work quickly when you are welding overheads. If you do not do so, the molten filler material instead of depositing on the target area will end up dripping on your face mask or face shield.
So, protection and skills are a must before doing welding. After placing both materials that need to be joined against each other, you need to use a specific stroke of your hand and move the welding material at the right speed to get the desired results. The selection of proper filler material is also necessary as it will determine and affect the results of the whole procedure.
Many kinds of filler materials are available for welding. You must choose the right one before doing welding. These materials usually come in three forms a stick, road, or wire.
What are the different types of weld beads and movements of the torch?
In most cases, manipulation of the torch is pretty the same whether you are using a mechanically thin fed wire, a thick and sticky electrode, or a separate filler rod. But, there are some methods and techniques available and each technique is used with a specific process.
There are many torch manipulation methods are available. Four of them are mostly used in welding. These techniques are divided into two groups i.e. main welding techniques and techniques specific to the process. Weave beads and stringer beads are the main welding techniques used in welding beads while whip motion or stick and walking cup (TIG) are techniques that are process specific.
Weld Bead Techniques: TIG or Walking the Cup:
TIG torch is mostly used on the root pass of pipe by welders. TIG can give you a precise and cleaner bead that you cannot obtain from MIG or stick welding. This process usually forms incorporation with a specific type of hand stroke which is called “walking of the cup.” The cup in this case is composed of a small or medium-sized ceramic insulator. The insulator is surrounded by a tungsten tip. A welder must move this cup forward and backward along the joint of the weld.
This method is mostly used for welding a large and wide area. This method can weld the area side by side on the joint area. For a thick and fat joint, weave bead is an economical and time-saving method.
Obviously, there are many different methods and beads available and every welder uses his favourite technique and beads. You can perform a curlycue, weaving, crescent, or zig-zag motion. This process can be done mostly in weaving and zigzag fashion.
Some weaving patterns that you must try when doing weave beads welding are as follows:
- Convex Weave
- Concave weave
- Ladder Weave
- Jagged weave
- Curlicue Weave
- Triangular weave
In the weld puddle, you can use a weave to control heat. Pausing on every side is also an effective strategy during welding. So, you must pause on all sides of the weaves. This step will help you in the prevention of edge undercutting and ensure a good tie-in of metallic pieces after welding.
When you are moving the weave beads across the metal, try to keep your pace moderate in the middle of the joint. If you keep your speed slow, you will form a small or perhaps large bulge (Crown) in the area depending upon the time. However, if you move rather fast, no proper weave will deposit on the area and will result in weak or no joint formation at all. So, during welding (weaving), it is a good practice to slightly convex or flat the face of the weld.
If there is a need to deposit and fill a slightly steep pocket, then a triangular weave can work wonders. For example in vertical or up welding, this weaving pattern allows you to create a shelf beneath the puddle. This will keep the metal in its place and will prevent the metal from sliding downward.
To prevent puddles from expanding or overheating, then semi-circle weaving pattern is a must-try. The central point of the weave must be ahead of the puddle or must be in front of it. If you need extra heat in your puddle, you must weave the crescent or semi-circle through the back of the puddle.
Weaving can also be done in an overhead position but it is the most challenging position due to gravity. The molten metal from the metal tends to move downward due to gravity. Weaving saves your time as compared to stringer beads.
It is a very straightforward process. In stringer beads, you either push or pull (drag) the welding torch over the joint. The movement of the torch must be in a linear (straight) path with minimal or no side-by-side movement.
Dragging or Pulling means the welding electrode or torch is placed on the target area of the joint in a forward angled direction. This will form the puddle on the target area during welding. These steps are necessary as they will result in a robust weld and maximum penetration of the welding molten material.
For thin metals or heat-sensitive materials, welders just push a slight tip of the welding torch. The same is done in the case of vertical welding of the materials. This method requires the welding torch leaning a bit away from the pool or puddle and you must follow the welding torch as you start welding the area.
Pulling the torch on the target metal is better than pushing. Pulling will result in good penetration in the target area than pushing. In most the cases, stringer bead is not very wide and therefore welding can be done in almost any position or posture.
Again, welding must be done in a linear and straight path, but you must tie in the toe-end of the welding torch on either side of the joint. Remember, the objective of welding is the fusion of the base metal with the help of filler. It is not just the filling of the joint area with metal fillers.
In some cases, a slow movement of the torch allows the molten material or filler to flow on both sides of the joint. This will help you in obtaining a very good fusion of the target area. Sometimes, a slight side-by-side manipulation can help you in achieving the required results as well. Make sure to keep the manipulation slight. Otherwise, if you move away, you will form weave beads on the target area.
Stringer beads can also be utilized in hard facing. Hardfacing is an operation on the surface. It will help in extending the age and life of fenders, plows, scoops, and some other exterior metallic parts of equipment. The beads are only meant to form a protective layer instead of fusion with base material in this case.
Whip Motion (Stick)
In open groove weldings, a welder using sticks performs a motion just like a whipping or lashing of a whip. He performs this motion with his hand and wrists to the roots of the material. E6010 and E6011 are the most famous and common stick electrodes.
The movement of the electrode must be up and in line with the gap to achieve complete and perfect penetration. In the beginning or opening, you might observe a keyhole that will appear in the puddle. It is a very difficult stroke that welders can learn. You must maintain the keyhole size by watching and comparing it with a puddle. If the keyhole becomes bigger more than enough, then you will not be able to form a proper fusion of two or more metals. Therefore, heat control is a very crucial process in root pass.
The frequency of the whip strokes will determine the size of the keyhole. Therefore, you can increase or decrease the size of the keyhole by increasing or decreasing the frequency of the strokes. If you observe an expansion of the keyhole too much then you should whip and move the rod a little ahead of the weld.
This step will cool everything and will keep the size of the keyhole constant. It also helps in solidifying the puddle. When the bead starts solidifying, you must whip back the puddle. This process happens very quickly. So you need to be active and alert. The rate at which you whip will depend upon the heat that you will observe from the puddle (weld).
As there is no heat, in the beginning, you do not need to whip. By the end of the procedure, enough heat is generated and you need to whip constantly at a steady rate at the metal base.
Variation of Whip:
Variation of the whip motion is also called as J weave. It is a combination of blends of whip strokes and crescent. It is mostly used in the 2nd pass of the groove V joint.
You should move the E6010 or some other fast-freeze electrodes from one point (toe) of the metal to another. A little pause on each side won’t hurt a lot. A longer arc will be helpful for you if you want to obtain better results. After whipping the torch ahead, you should whip back on the next area on the right (or left) of the toe end of the weld and then repeat it.
As we have discussed so far, the filling and formation of the joint are heavily dependent upon the movement of the welding torch. The movement is highly specific as in the case of wider joints. Information, expertise, and proper understanding of various welding techniques can greatly improve the quality and after results of the welds.
As you know, preparing the joint, setting up the area of the welder correctly, and picking up the right filler material can improve the results and quality of your welds. Butt, you cannot ignore the importance of the movement of the welding torch. It helps in creating the right bead size for your welds.
The methods covered so far in this article can provide you with a solid and good start. But, some of the things must be kept in mind while welding. There are a lot of variations and very fine details that you need to master to become an expert in the manipulation of torch and torch movements.
The best method to obtain mastery and expertise in this field is through regular practice. You need a lot of practice to become a master in this field. Practice makes a man perfect.