Top 10 Things to Teach Novice Welders
December 18, 2011
Learning to weld is no easy task. It takes patience, practice and a solid foundation of knowledge. For companies who find themselves faced with the challenge of training novice welders, it is important to instill good habits early on in the training process. Doing so helps ensure that these individuals are well prepared not only to create quality welds, but also to contribute positively to the overall welding operation. It can also help the welders gain the confidence they need to become increasingly proficient. Following are 10 important things to teach novice welders, to help them improve their skills and stay safe in the process.
1. Make safety a first priority: It is critical that welders protect themselves from the heat and electricity generated by the welding process. The arc is dangerous to both the eyes and skin, and welders need to wear the proper personal protective equipment (PPE) at all times. These items include: flame-resistant gloves, safety glasses, a welding helmet and a long-sleeved welding jacket. Flame-resistant clothing and steel-toed shoes are also recommended. Both the American Welding Society (AWS) and OSHA offer guidelines for PPE for specific environments.
It is also important for welders to use enough ventilation, local exhaust at the arc, or both to keep the fumes and gases below the Permissible Exposure Limit (PEL)/Threshold Limit Value (TLV)/Occupational Exposure Limits (OELs) in their breathing zone and the general area. Always train new welders to keep their heads out of the fumes. Too, explain to new welders the importance of reading and understanding the manufacturer’s instructions for equipment, your company’s safety practices, and the safety instructions on the label and the material safety data sheet for the filler metals being used. In short, remind novice welders to take all necessary precautions to protect themselves and others.
Routinely checking for proper ground connections and standing on a dry rubber mat (indoors) or a dry board (outdoors) during welding can further protect welders by minimizing the possibility of electrical shock.
2. Install Consumables Properly: Good conductivity (the ability for the electrical current to flow along the welding circuit) is an important factor in gaining good weld quality. New welders should always install their consumables – diffusers, nozzles, contact tips, collet bodies, etc. – according to the manufacturer’s recommendation, making sure that each component is securely tightened. In a gas metal arc welding (GMAW) operation, for example, the connection between the GMAW gun neck and diffuser needs to be secure to prevent shielding gas leaks. Secure connections also provide the surface area necessary to carry the electrical current throughout the GMAW gun (or gas tungsten arc welding – GTAW torch) to create a stable arc. Good connections also help prevent weld defects, support consistent productivity and reduce the risk of premature consumable failure due to overheating.
3. Cleanliness is critical: Cleaning the base material prior to welding, and as needed between weld passes, is absolutely essential. Dirt, oil, grease and other debris can easily enter the weld pool causing contamination that leads to poor weld quality and costly rework. Excessive oxidation and moisture are also culprits that can compromise quality weld. New welders need to be educated as to the proper cleaning procedure for the particular base material they are welding. In some cases, wiping the base material with a clean, dry cloth may suffice. However, welding on aluminum, for example, takes more precautions. The welder will need to use a stainless steel wire brush designated for aluminum to clean out the joint before welding. A wire brush removes dirt and any of the oxides that may still reside on aluminum’s surface.
Regardless of the material, it is important to provide the welder with the proper instructions for cleaning before welding commences.
4. Always follow welding procedures: Welding procedures are the “recipe” needed to create consistent welds. New and experienced welders alike need to understand the importance of these procedures and should follow them at all times. The procedures for a given application have been carefully determined and qualified by experts to ensure that the recommended parameters are capable of yielding the desired results. Weld procedures include details such as the required shielding gas mixture, recommended gas flow rate, and voltage and amperage ranges. These procedures also provide information on the type and diameter of filler metal to use, as well as the proper wire feed speed in the case of a GMAW or flux-cored arc welding (FCAW) application.
5. Understand the importance of filler metals: Filler metals are a critical, but sometimes confusing, component of the welding system. New welders can benefit from familiarizing themselves with the attributes of various types of wires, including flux-cored and metal-cored wires, as well as the techniques for welding with each type. For example, they should learn whether their particular filler metal requires a “push” or “pull” technique. Following old adages like, “If there’s slag, then you drag,” can help; it indicates that flux-cored wires, which produce slag, should be operated using a pull technique. New welders should also establish the habit of consulting the manufacturer’s specification sheet for additional operating recommendations.
Learning to handle and store filler metals properly is also critical for new welders to learn. They should always wear clean gloves when handling filler metals and if they are responsible for storing them, should do so in a clean, dry environment.
6. Stay comfortable: Keeping cool and comfortable during the welding process can help welders lessen the chance of injuries associated with repetitive movement and reduce overall fatigue. When possible, welders should learn to minimize cumulative strength moves, material handling or constant motion. They should also use a GMAW gun or GTAW torch with a comfortable handle and cable style, as these factors both contribute to the equipment’s weight and maneuverability. New welders should be encouraged to play an active role in improving the ergonomics of their welding workspace. Typically, the more involved a welder is in providing input about the job, the more satisfied he or she will be. Plus, such active involvement can help ensure greater safety compliance and lower workers’ compensation costs for injuries.
7. Know the material properties: Every material has different mechanical and chemical properties. Helping new welders understand the difference between materials — particularly how they react to heating and cooling — is a key component of training. For example, austenitic stainless steel conducts heat at around half the rate of mild steel, but has a much higher rate of thermal expansion when welded; it also has a more localized heat affected zone (HAZ) that can lead to buckling when the weld cools. Welders who are aware of such properties can take precautions such as clamping to prevent distortion. Similarly, many materials require pre- and post-weld heat treatments to control the cooling rate and prevent cracking. When welders are familiar with such material attributes, they’re better prepared to make necessary adjustments during the welding process.
8. Visually inspect the welds: Knowing how to conduct an accurate visual inspection of a completed weld is the first step in quality control. It is also the quickest and least expensive method of inspection. New welders should learn how to identify weld defects that have porosity, for example, since the presence of this weld defect on the surface often indicates a similar problem throughout the weld. Identifying the defect early on helps prevent the time and cost associated with other testing methods, including x-ray or NDT (non-destructive testing) inspections. Other defects that welders should learn to identify include lack of penetration (high, ropey welds), excessive penetration (sunken welds) and undercutting (characterized by a notch in the base material). It is important, too, that welders inspect for weld cracks, which are among the most common weld defects to occur in the welding operation.
9. Learn how to troubleshoot: Being able to identify and rectify welding problems quickly is a key skill for new welders to learn. Good troubleshooting skills not only help reduce downtime, but they also contribute to good weld quality and productivity. Such skills can also help reduce costs associated with rework. New welders can benefit from learning how to adjust gas flow rates properly and/or identify gas leaks in order to solve instances of porosity. They should also know how to make adjustments to amperage and voltage settings if they encounter issues such as lack of penetration, excessive penetration or undercutting. Identifying welding problems associated with worn consumables is also important, since poor conductivity can result in an unstable arc and lead to a variety of weld defects.
10. Maintenance makes a difference: From the power source to the GMAW gun or GTAW torch and consumables, every part of the welding system requires maintenance to keep it operating efficiently and effectively. New welders should become familiar with proper maintenance procedures — preferably preventive ones — in order to play an active part in the ongoing upkeep of the entire welding system. Regularly checking that the connections throughout the length of their gun or torch are tight is important, as is visually inspecting the front-end consumables for signs of wear. In the case of a GMAW gun, the welder should replace nozzles or contact tips that have spatter buildup on them to prevent issues such as poor gas coverage or an erratic arc that will likely lead to weld defects. Welders should also regularly check the power source, primary power line, gas cylinders and gas distribution system to ensure that they are working properly. They also need to replace faulty gas regulators or cables and hoses that show signs of wear, cracks or damage.
There is more to teaching a novice welder than just showing him or her how to set the power source or hold the gun or torch at the correct angle. The best approach to training is to incorporate good habits that will keep the welder safe and comfortable, and provide the knowledge to address everything from maintenance to materials. The time required to transition a novice welder to a skilled one will, of course, take time. Still, the long-term benefits are worth it.