Introduction
Shielded Metal Arc Welding, or SMAW, is a dependable and flexible welding process that’s been around for a long time. It’s one of the few processes that handle just about any kind of material and various thicknesses with ease. Although it’s not used to fabricate intricate parts or pipework—those are jobs for other, more specialized processes—it’s a process that can and does find a place just about anywhere else. In this process, the filler metal is supplied by a consumable electrode. As the name implies, the electrode is shielded from the atmosphere by an arc and a coating of flux. The arc produces heat as it moves along the joint, and the heat melts the electrode and base materials to form the weld pool, which then cools and solidifies to become the finished weld.
What are Stick Welding Electrodes?
Electrodes used for stick welding consist of metal rods that possess a flux coating, and they are fundamental to the welding process. An arc gets established between the coated electrode and the workpiece. Both the coated electrode and the workpiece’s metal composition, where the arc is occurring, start to melt. The metal from the coated electrode transforms into weld metal, while the base metal components of the workpiece also become part of the change. The flux coating does not change and only acts as a means of containing and directing the heat and light of the arc properly.
Why Choose Stick Welding Electrodes?
Welders use stick welding electrodes for several reasons. First, these special rods can be used for a great variety of metals—more or less anything, in fact, that can be melted. Second, and perhaps super-important when I’m trying to boost my ego, is portability. It’s not hard for a spirited young workman to carry a bunch of these rods, a holder, and a few basic tools around at a jobsite. Third, with a steady hand, a welder using stick rods can deposit a good-looking (if not pretty) bead in any position. That’s right: Stick welding can be done flat, horizontal, vertical, or overhead; with both hands (like the MIG gun); or with only one hand, if desired. And when the welding is all done, stick welding holds up better in the wind than wire does.
Types of Stick Welding Electrodes
- Stick welding electrodes come in several types, depending on the type of “flux cover” they have since the cover, or “flux,” is what helps to create the welded joint. It is the part of the electrode that covers the metal tip, which, when combined with the heat of the arc, melts and fuses filler metal into the joint. The various types of coverings on the different electrode types are discussed in detail in Lab 6 and are summarized here for your convenience.
- Before anything else, let me offer a couple of additional remarks. When you use a stick arrangement to weld, there’s a good chance that you’re going to run into arc blow. Stick welding is still, largely speaking, a hands-on, very manual process. A good deal of what you get and don’t get in this process boils down to being skilled in controlling the arc. In our intro to this series on welding, we encouraged you to take a good, close look at the work of your school of choice and what alumni from that school are doing today. Why? Because learning to do anything worthwhile… and stick welding is no different… takes practice and proficiency.
- Now onto the different types of electrodes and their coverings.
Choosing the Right Stick Welding Electrode
Many factors go into choosing the right stick welding electrode. One is the type of metal you are working with. This will dictate the composition of the electrode you should use. You should also consider the thickness of the materials you are working with, as it will affect the amperage rating and the electrode’s capability for deep penetration. When choosing the right electrode diameter and type, we shouldn’t forget to look closely at the kind of joint we want to make and how we will make it. This is important because the type of joint can demand that we use a larger or smaller electrode and can require us to consider the joint’s mechanical properties. What happens to the joint and the weld after we walk away? They should still work; in fact, we can, and should, consider an electrode’s selection in terms of the joint’s mechanical properties as well.
Tips for Using Stick Welding Electrodes
- Here are some different ways to express those ideas:
- It is important to keep electrodes in a dry place so that they don’t get water damaged, which can really affect the way they work.
- When you’re starting your arc, it’s best to do it with a scratching or tapping motion. These are the best ways to not only initiate the arc but also to not leave marks that could damage the weld or the electrode for future welds.
- Keep that arc length just right. Experts suggest that the groove your arc is making between metal pieces should be about the same length as the electrode. If it gets too short, you’ve got some serious undercut going on. Too long and your metal is going to stretch and not form the basis for a real weld.
- Adjust your travel speed. If you’ve ever used a puddle of water to put out a fire, think of those little droplets of water as your weld beads. Those form the structure inside your weld. Move your torch too fast or too slow and you’re either stretching the size of the puddle or not allowing enough heat to be built up to do the weld right.
Conclusion
Electrodes for stick welding are a tool that is used in a wide variety of applications and industries. Welders understand the different types of electrodes and select the right one for their current project. This is crucial because the strength and durability of the weld are dependent on the type of electrode that is used. The appearance of the weld is also important from a visual standpoint. Hence, an understanding of all these aspects is essential to ensure that the electrode used in the stick weld process is the right one for the job.
Find more information about welding wire and welding techniques at UDO website – https://www.udo.co.th/
