October 15-17, 2024 at Orange County Convention Center in Orlando, Florida
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Tuesday Oct 15 9 AM — 5 PM
Wednesday Oct 16 9 AM — 5 PM
Thursday Oct 17 9 AM — 4 PM

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Orange County Convention Center

9800 International Drive
Orlando, Florida 32819

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North America's largest metal forming, fabricating, welding and finishing event heads to Orange County Convention Center in October 2024. FABTECH provides a convenient "one stop shop" venue where you can meet with world-class suppliers, see the latest industry products and developments, and find the tools to improve productivity, increase profits and discover new solutions to all of your metal forming, fabricating, welding and finishing needs.

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North America's Largest Metal Forming, Fabricating, Welding and Finishing Event

From the Blog

Keys to Success for a New Welding Engineer

By Jennifer Dallos on on
Why it is critical that a welding engineer become knowledgeable in what welding standards exist and how they must be applied By RICHARD HOLDREN, a PE, AWS SCWI, and IWE, is a senior welding engineer with Arc Specialties Technical Services, Houston, Tex, and president of Welding Consultants, LLC, Columbus, Ohio. Reprinted with permission: The Welding Journal One of the biggest challenges for a welding engineer, especially when newly introduced to the position, is to understand the myriad welding requirements existing for various applications. Just determining the applicable welding standard for a given application can be a challenge. Once this has been established, the next task becomes the interpretation of welding requirements related to qualification, inspection, and acceptance criteria. Few schools provide instruction in this aspect of the job, so on-the-job training and experience are the primary means of gaining this knowledge. Becoming proficient requires years of experience. While there may be a shortage of training in the specific activity of standards selection and application, a welding engineer is considered relatively well prepared for this challenge. Welding engineering curricula require individuals to be exposed to the broad-ranging areas of expertise, including, but not limited to, welding design, materials, welding processes, and welding inspection and quality control. On a daily basis, a welding engineer may be required to interpret and apply drawings, specifications, and other related standards to understand the applicable fabrication and quality requirements existing for the job at hand. While it is not recommended for a welding engineer to commit this vast amount of information to memory, he/she must become proficient in maneuvering through the world of welding standards. To be successful, a welding engineer needs to realize that certain ground rules exist. While many products could not be effectively manufactured without welding, some designers either don’t understand welding or the standards governing welding design, and this often results in overly conservative designs that can give rise to the creation of designs and configurations that are less manufacturable. This may be further complicated by the stipulation of overly restrictive quality requirements. A welding engineer must understand these limitations. Few companies are of a size to warrant a separate welding engineering department or group, so most often a welding engineer is found in a manufacturing engineering position, which is an excellent environment because a welding engineer’s training makes him/her well suited for observation and control of the applicable manufacturing or fabrication processes, including welding and other ancillary technologies. I have also experienced situations where a welding engineer functioned as a part of the quality organization. In these cases, results were excellent since there was an effort to ensure that welding was being performed in a manner that would reduce scrap and rework, and therefore improve productivity. When the focus is placed on quality, the overall result is positive in terms of meeting both productivity and quality goals. Consequently, one of the keys to success for a welding engineer is to become fully aware of the quality requirements so that these goals can be attained in the most effective manner. Part of this awareness is to understand the distinction between weld quality and welding quality. While the two terms are considered synonymous, there is a subtle difference. Weld quality relates to the attributes of the finished weld in terms of attainment of the prescribed quality requirements. Welding quality is a more inclusive term, as it relates to not only the finished product, but also to all of those design and manufacturing steps affecting the resulting weld quality. It is this area where a welding engineer can be most effective in terms of ensuring that the required quality levels will be achieved. Consequently, the welding engineer must also be aware of the preliminary and in-process requirements and controls necessary to ensure that the manufacturing process will be successful. Quality Considerations Prior to Welding To ensure success, the emphasis on quality must begin long before the welding inspector examines the completed weld. In fact, the path to achieving the prescribed quality goals begins in the design stage of a project. If a product is not designed with an awareness of how the welding and other manufacturing operations will be performed, it may not yield a successful result. So, an area where a welding engineer can be most effective is in the execution of a design review. Some of the critical factors to be considered are as follows:
  • Is the product manufacturable? That is, can it be effectively manufactured to meet the quality and productivity requirements?
  • Does the specification and drawing package contain all of the detailed information necessary to execute the design?
  • Are all welding symbols present and correct?
  • Are the applicable welding standards clearly identified?
  • Are the weld acceptance criteria clearly specified?
If any of this information is missing or incomplete, it may be difficult to produce an acceptable product in an effective and efficient manner. Another preproduction concern for a welding engineer relates to qualification of welding procedures and personnel performing the welding. While this can be a costly activity, it is critical that a welding engineer have a clear understanding of the applicable standards and job specifications so that any qualification testing performed results in the maximum coverage for both the existing job as well as potential work. Some of the items to be reviewed include:
  • Do the drawings and specifications clearly specify the requirements for procedure and performance qualification?
  • Do existing welding procedures satisfy the current job requirements? If existing procedures have been qualified in accordance with some other welding standard, will the customer accept those in lieu of the applicable specifications for the job?
  • Are welding personnel properly qualified?
  • If additional procedures or personnel require qualification, be aware that the acceptance criteria for the required qualification test welds are not necessarily the same as the acceptance criteria for production welding.
  • If necessary to perform additional qualification testing, develop a qualification program that will result in the maximum coverage for the procedure or performance qualification, even if greater than that required for the current job being considered.
One of the ways a welding engineer can get the most bang for the qualification buck is to perform qualification testing in accordance with AWS B2.1, Standard for Welding Procedure and Performance Qualification. This is AWS’s general qualification standard and is recognized by virtually all of the other AWS fabrication standards. AWS D14.3 and D17.1 directly specify that welding procedures be qualified in accordance with AWS B2.1. Most of the other AWS standards allow AWS B2.1 to be used as an alternate to qualification requirements in those respective standards. Consequently, if procedures are qualified in accordance with AWS B2.1, there is potential for those procedures to be applicable for use when working to a variety of AWS standards. Additionally, AWS B2.1 is essentially equivalent to ASME Section IX, so AWS B2.1 qualifications may also be employed when doing ASME work. Like ASME Section IX, AWS B2.1 groups materials with similar weldability so that when a base material from a given M-number group is used for the qualification test, the procedure is qualified for use with any of the other materials from that same M-number group. This can be a tremendous benefit when working with AWS D1.1 and using a nonapproved base metal. Per AWS D1.1 requirements, this requires that a procedure be qualified by testing, and that procedure is only applicable for that single base metal. Employing AWS B2.1 would allow that procedure to cover the welding of all of the base metals in the same M-number group. Additionally, welding position is a nonessential variable for AWS B2.1; however, D1.1 requires procedure qualification testing in all positions to be used in production when prequalified procedures are not applicable. Another advantage of AWS B2.1 is that Standard Welding Procedure Specifications (SWPSs) exist. These SWPSs are based on results from actual welding procedure qualification testing and are developed using the essential variables of AWS B2.1. Users can purchase these SWPSs and use them without the need to perform qualification testing, resulting in tremendous savings. Many of these SWPSs are recognized by both ASME Section IX and the National Board Inspection Code (NBIC). A series of these SWPSs are being developed for use by suppliers of weldments for Navy ship construction. More than 30 SWPSs have been developed and are available for purchase from AWS. A number of AWS standards, including AWS D1.1, D1.6, and D14.3, have allowance for the use of Prequalified Welding Procedure Specifications (PWPS). These procedures can be developed based on the applicable limitations of the AWS standard and can be used for production welding without the need for any procedure qualification testing. To develop a PWPS, the user must document the essential variables specified in the applicable standard and create a written PWPS, but no testing is required. Another area where a welding engineer can potentially provide valuable input to improve both quality and productivity is in the selection of processes and consumables to be used. Gas metal arc welding (GMAW) tends to be a workhorse in today’s manufacturing world. The process has numerous variations in terms of both electrical characteristics and welding consumables, so selection of the best combination for a given application is critical. One of the options available is the mode of metal transfer to be used. Greatest productivity can be achieved when using spray transfer; however, its use is limited in terms of both base material thickness and position. When welding out-of-position (other than flat position), welding thin sections, or when welding joints without backing, one’s choices are limited to either short circuiting transfer (GMAW-SC) or pulsed (GMAW-P). Use of GMAW-SC requires separate procedure and performance qualification per AWS B2.1 and D1.1, and its use is limited in terms of thickness for ASME Section IX. GMAW-SC also has limitations related to its potential for creation of incomplete fusion when used for joining thick sections. While GMAW-P is a suitable replacement for GMAW-SC for many applications, it requires a welding power source capable of producing pulsing output power. An alternative to this solution, which can be costly, is the use of metal core electrodes in lieu of solid wire electrodes. Because of their configuration, metal core electrodes operate at a higher current density. This allows metal core electrodes to be used for applications requiring either GMAW-SC or GMAW-P without the need to invest in costly pulsing power sources. Additionally, metal core electrodes melt more efficiently resulting in a 15–20% increase in deposition rate at a given amperage level compared to solid electrodes. Consequently, the change from solid to metal core electrodes can result in very cost-effective productivity improvements. When adjusted properly, metal core electrodes can be operated with essentially no spatter, so the amount of cleanup required after welding is negligible, equating to even further savings. Quality Considerations during Welding Once production welding begins, the focus for the welding engineer changes to the assurance that the quality plan is being properly executed and the welding is being performed in accordance with the qualified welding procedure(s). Among the concerns at this stage of the production process are as follows:
  • Are the proper consumables being used?
  • Have the consumables been properly stored and are they in good condition?
  • Are the required preheat and interpass temperatures being maintained?
  • Are welding personnel properly qualified, and more importantly, do they understand the limitations of the welding procedure and quality requirements?
  • Is welding being done in accordance with the applicable fabrication requirements?
In order to meet the dimensional requirements for a weldment, the welding engineer may need to develop a plan for controlling distortion. To accomplish this, the first step is to understand what dimensional requirements exist and whether postweld stress relief will be employed. Production adjustments necessary to limit distortion may include
  • Use of weld sequencing
  • Use of subassemblies
  • For welding thick sections, consideration of welding from both sides of a joint to balance the shrinkage stresses.
Quality Considerations after Welding At this stage of the process, little can be done to alter the result of the preceding steps. As is often said, quality cannot be inspected into a product. After welding, the activities involve verification that the fabrication steps have been successful to result in an acceptable product. The most important concern at this point is to be certain that there is a clear understanding of the applicable quality requirements in terms of both weld quality and dimensional accuracy of the completed weldment. The applicable acceptance criteria must be known and understood throughout the fabrication process; however, after welding is complete, it is critical that these acceptance criteria are properly interpreted and applied during the inspection process. While desirous that welds be produced without any discontinuities, this is impractical. That’s why welding standards exist. They provide limits on discontinuities that, when achieved, will result in a product that will perform as designed and intended. A welding engineer must have a clear understanding of these requirements so that resulting welds can be defended. For this part of the job, a young welding engineer is encouraged to become an AWS Certified Welding Inspector (CWI). Every welding standard incorporates its own set of acceptance criteria, so maneuvering through this maze is the first challenge for a welding engineer. Below is a list of some of the application-related welding standards the welding engineer may be exposed to.
  • Structural welding (AWS D1.1 through D1.9)
  • Piping (Cross-country pipelines – API 1104, Power piping – ASME B31.1, Petrochemical piping – ASME B31.3)
  • Pressure vessels (ASME Section VIII)
  • Boilers (Power – ASME Section I, Heating – ASME Section IV)
  • Aerospace (AWS D17.1)
  • Specialty apparatus (Industrial and mill cranes – AWS D14.1, Construction and agricultural equipment – AWS D14.3 and D14.4, Rotating elements of equipment – AWS D14.6).
Within the context of this discussion, it is impractical to cover the weld acceptance criteria for all of these standards. Since AWS D1.1 is considered to be the dominant AWS welding standard in terms of its use both domestically and internationally, the discussion below addresses some of the weld acceptance criteria found in D1.1. The requirements found in the other D1.X codes are quite similar, as D1.1 has been the model for the others. Understanding the Weld Quality Requirements of AWS D1.1 For any project where AWS D1.1 is the applicable standard, the first question to be asked relates to the classification of the welded structure. This applies not only to the acceptance criteria to be applied, but it also dictates some of the fabrication requirements. D1.1 classifies structures as one of three types: statically loaded, cyclically loaded, or tubular. This is especially important for the inspection effort, since different acceptance criteria are specified for each type of structure. Some of the highlights of these acceptance criteria are discussed below. Table 6.1 summarizes the visual weld acceptance criteria for all types of structures. Some of the criteria are identical for all types of structures; however, a couple, porosity and undercut, vary with the type of structure. Requirements for weld profile are found in the fabrication clause in section 5.24. What is curious here is the fact that the weld profile has perhaps the greatest impact on the performance of a weld when subjected to fatigue, i.e., cyclically loaded, service. However, D1.1 makes no distinction between the weld profile requirements for the different types of structures. Without differentiating, there exists a potential for acceptance of weld profiles that will not perform as desired when placed in fatigue service. There are also issues related to the manner in which the code limits weld profiles. By current A3.0 definitions, there are three weld profile conditions that can be quantitatively measured — convexity, overlap, and weld reinforcement. Convexity is a characteristic exclusively applied to fillet welds and is defined as, “The maximum distance from the face of a convex fillet weld perpendicular to a line joining the weld toes.” Its counterpart, weld reinforcement, is only applicable to groove welds and is defined as, “Weld metal in excess of the quantity required to fill a weld groove.” The final profile characteristic, overlap, is applicable to both fillet and groove welds and is defined as, “The protrusion of weld metal beyond the weld toe or weld root.” In the current edition of D1.1, overlap is not limited and both convexity and weld reinforcement are limited by a dimension. In the case of convexity, this limiting dimension is virtually impossible to measure with conventional tools used by the welding inspector. In the current edition of D1.1, the dimension for convexity is limited in terms of weld face width, so a specific amount of convexity is allowable for a range of weld sizes.      To truly limit the profile of a weld, the single characteristic defining profile is the angle formed between the weld face and the adjacent base metal surface at the weld toe. In a weld consisting of multiple beads across the weld face, angles formed between adjacent beads also form part of the weld profile. In the next edition of A3.0, these angles have been proposed to be termed reentrant angles, defined as, “The angle formed between a line tangent to the weld face or root surface and adjacent base metal surface at the weld toe or weld root, respectively. In a multipass weld, the angle formed between lines tangent to adjacent weld bead surfaces at a weld bead toe.” It has been proposed that the existing limits on convexity and weld reinforcement, which indirectly affect profile, be replaced, or at least supplemented by limits for reentrant angle. Reentrant angles can be easily measured with simple, template-type gauges. A further benefit of this approach is that separate limits could be specified for statically loaded and cyclically loaded applications. This same approach has been implemented in AWS D14.4. The whole point of this discussion is that not only is it important for a welding engineer/inspector to understand the acceptance criteria, it is also important to know how to measure characteristics. For weld profile inspection, a welding engineer may find it beneficial to suggest alternate means of limiting weld profile characteristics, which can be more easily and consistently measured. A couple of other inspection issues a welding engineer needs to be aware of when AWS D1.1 is being used relate to the requirements for porosity and undercut. It was mentioned earlier that both of these discontinuities have different limits depending on the type of structure. Additionally, in the case of porosity, only piping porosity is considered rejectable. Per the limits of D1.1, any other form of porosity is not considered rejectable, regardless of size or the type of structure. This distinction leads to disputes since various entities, such as design engineers and customers, may not understand the significance of the type of porosity being limited. A further complication is that, for cyclically loaded structures, there is a difference in the porosity limitation depending on the direction of the principal tensile stress with respect to the weld. To make this determination, the design engineer must be consulted. This same problem exists for the undercut requirements for cyclically loaded structures. These examples come from AWS D1.1, but similar interpretation/application issues can be found in many of the other industry standards. Visual examination of welds is not a straightforward activity, because it requires the inspector to use tools to assist with measurements and judgment in terms of whether the physical attributes of the weld meet the written acceptance criteria. At times, this can be challenging, especially for the inexperienced welding engineer. This is expected and helps to explain why there is no replacement for experience. That’s the only way one becomes effective and efficient in the art and science of welding inspection. Ending Thoughts So, keys to success for a new welding engineer so that he/she becomes effective in this position are numerous, as has been explained here. It is critical that a welding engineer become knowledgeable in what welding standards exist and how the requirements are to be applied. These documents will provide the technical basis for your success in this position. The better you know the contents of these standards, especially those related to qualification, fabrication, and inspection, the more successful you’ll become. Becoming proficient with these requirements will allow you to succeed. One problem you will often encounter are situations where other individuals attempt to apply their own “requirements” that are in excess of those required by the applicable Code or specification. Your best defense is to have a better understanding of the real requirements through your knowledge and experience.

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