Recommendations for Visual Testing of Welds

Visual Testing Responsibilities before Welding and Fabrication Work

Project Drawings and Specifications

• Obtain all current project drawings, specifications, and applicable codes that pertain to the project welding requirements.
• Verify that these documents are current.
• Review all details and information on construction, focusing on welding and welding inspection requirements.
• Know the project requirements for all welding operations.
• Use the project drawings, specifications, applicable codes, and the welding procedure specifications (WPS) to execute the following inspection responsibilities before, during, and after welding.
• Stamp one set of project drawings and specifications with the acronym QC (quality control) for formal records of inspections, acceptances, notes, and additional QC information.
• Prepare to submit, upon completion, the QC copy of project drawings and specifications for QC records. Submit, with these documents, all related information in one QC project file. This may include material test reports, nondestructive testing (NDT) reports, and welder certification credentials.

Purchase Order Specifications

• Use the project requirements, including specifications and applicable codes, to identify specific material grades and stock.
• Review supplier proposals, purchase orders, and subcontracts to verify the materials being ordered will meet the project’s requirements.
• Verify that purchasing has requested any required material testing reports from the supplier at the time of the order.
• Confirm base steel materials through resources, such as the American Society for Testing and Materials (ASTM), for standardized grade identification; for example, a resource is ASTM A572, Standard Specification for High-Strength Low-Alloy Columbium-Vanadium Structural Steel.
• Ensure that proper filler metal is purchased.
• Confirm filler metal materials through the applicable AWS specification, such as AWS A5.1, Specification for Carbon Steel Electrodes for Shielded Metal Arc Welding.
• Consult AWS codes and guidelines, such as AWS D1.1, Structural Welding Code — Steel, when specified in the project documents.

Job Materials

• Confirm that the received materials match the ordered materials.
• Verify the delivered job materials against the project specifications as a secondary check prior to any work being performed.
• Mark identification grades or job numbers, or both, on all pieces if the materials arrive without such designation. Many metals look alike; therefore, the potential for inadvertent material mix-ups is high.

Chemical Analysis and Mechanical Properties Test Reports

• Use the project specifications to determine any special material testing reports that may be required.
• Check all shipping documents for any material test reports.
• Save all reports, such as chemical analysis, mechanical properties tests, mill certifications, and any other material test certificates or reports for QC documents.
• Contact suppliers immediately should any required test reports be missing.
• Refuse any materials from suppliers that will not furnish proper material test reports.

Investigate for Base Metal Defects

• Examine base metals for discontinuities. Remember that all discontinuities do not warrant a defect.
• Consult the engineer if discontinuities that may warrant a defect are present.
• Check the availability of replacement materials.
• Reject defective materials when replacement materials are readily available for exchange.
• Discuss alternatives to rejection (i.e., repairs) with the engineer in the event that long lead time items may affect project completion timelines.
• Discuss repair costs, materials replacement availability, schedule, and other factors with project managers and engineers.
• Complete the investigation and consult with the engineer.
• Approve materials or plan for replacing or repair, or both, at the approval of the engineer.

Proper Filler Metal and Condition of Storage and Filler Metals

• Verify filler metal meets project or job requirements.
• Receive and maintain documentation from manufacturers, including safety data sheets, technical data sheets, and certificates of conformance, along with any other documents required by project specifications.
• Check filler metal packages for proper condition and storage.
• Inspect the packaging for damage.
• Verify that hermetically sealed containers provide a nonpermeable barrier to the passage of air or gas in either direction.
• Reject or return any damaged packages — store filler metals in a protected, clean, and dry location with continuous electrical service.
• Employ an electrode oven or warmer for open electrodes of all low-hydrogen electrodes.
• Verify the accuracy of electrode oven or warmer with a thermal device or temperature-indicating crayons.
• Verify posting of proper AWS electrode exposure limitations table in immediate proximity of filler metal storage location.

Welding Equipment

• Verify that the welding machine possesses its proper identification number, traceable to an annual certificate of calibration, including machine manufacturer, model, serial number, and date of calibration.
• Inspect the machine for safe operational capability, general condition, and suitability to perform the specified welding operations.
• Check WPSs for parameters to verify the machine is appropriate for the work.
• Inspect welding machine accessories, including leads, work return clamp, electrode holder, electrical service connector, and all other features.
• Confirm suitable electrical service is available for electric machines.
• Verify the availability and condition of any additional welding equipment the work will require, such as torches, grinders, extension cords, clamps, and other tools and equipment.
• Consider any welding safety equipment requirements, such as fume extractors, welding screens, fire-resistant blankets, fire extinguishers, water spray cans, and other equipment. Ensure that all welding and safety equipment is onsite and in good working order.

Weld Joint Edge Geometry

• Use project drawings and specifications to verify joint edge geometry requirements.
• Check materials at weld joint for proper cuts, bevels, root face, copes, or other preparations. Measure geometric features with a machinist’s rule, angle finder, protractor, or other precision tools to ensure proper joint edge geometry.

Weld Joint Fit

• Check the weld joint for proper fitup.
• Use the project drawings to determine joint type: butt, corner, edge, lap, or T-joint.
• Use the machinist’s rule or other precision tools. Verify the joint alignment, gapping, backing straps, and other features. Weld Joint Cleanliness
• Check the weld joint for cleanliness prior to welding.
• Inspect the joint for any contamination such as oil, grease, moisture, mill scale, rust, or paint.
• Require proper surface preparation such as cleaning, heating, or grinding.
• Reinspect any cleaned or prepared weld joint surface prior to welding.

Welder Qualification Check

• Review the welders’ certification records to determine their qualifications.
• Ensure that each welder’s certification record references AWS D1.1 or applicable code.
• Review the welder performance qualification record, photographic identification card, and continuity log book for current and appropriate data.
• Confirm that the records conform to the process, position, material grade and thickness, and current status for the welding requirements of the project.
• Copy all of the noted documents for QC records.
• Preheat Temperature Requirements
• Use the project specifications and applicable code to confirm preheat temperature requirements.
• Verify that the WPS directs the preheat temperature requirements.
• Ensure that the proper tools and equipment (with the proper temperature ranges) will be available to produce and check preheat temperature.

Visual Testing Responsibilities during Welding and Fabrication Work

Production Welding for Compliance with Welding Procedure

• Use the WPS to regulate welding operations.
• Ensure that the variables of welding operations such as polarity, amperage, technique, travel speed, and others fall within the ranges of the parameters on the WPS.
• Ensure that the fixed requirements such as welding consumables, weld profile, contour, dimensions, and others are kept compliant with the WPS.
• Keep the WPS available to the welder, supervisor, and inspector at all times.

Quality of Individual Weld Passes

• Check the individual weld passes prior to the deposit of overlaying passes. Inspect for weld profile, surface discontinuities, excessive convexity, notches, and other poor characteristics that must be corrected before additional weld deposits or passes are made.
• Inspect for excessive discontinuities, defects, or cracks that must be rejected, removed, and inspected prior to continuing welding operations. Document the inspection of passes on QC drawings. It is particularly essential to inspect the root pass on a multiple-pass weld thoroughly. This is the most challenging weld deposit. Overlaying passes may not fuse properly if the root pass contains discontinuities.

Interpass Cleaning

• Verify interpass cleaning on multiple- pass welds.
• Inspect for complete slag removal to prevent slag inclusions and incomplete fusions.
• Thoroughly inspect welds with convex profiles, which may make complete slag removal difficult.
• Require grinding when excessive convexity prohibits sufficient access to the slag coating.

Interpass Temperature

• Use the project specifications and the WPS to determine interpass temperature requirements.
• Confirm that the proper tools and equipment are available to perform and check this function, such as properly rated temperature-indication crayons.
• Verify that the welder or welder’s helper is properly heating and checking interpass temperature.

In-Process Nondestructive Testing

• Use the project drawings and specifications to determine if in-process NDT is required.
• Select NDT laboratories or technicians qualified by the American Society for Nondestructive Testing (ASNT), Recommended Practice No. SNT-TC-1A: Personnel Qualification and Certification in Nondestructive Testing.
• Know the project requirements for NDT. Schedule NDT effectively by confirming a contract with the NDT company ahead of the intended timeline.
• Monitor welding operations and activities as they approach expected timelines for NDT.
• Anticipate when the project will be ready for the required NDT.
• Follow up with the NDT lab a minimum of one week ahead of the anticipated need for the services.
• Keep the project schedule on its intended timeline by facilitating NDT services to accommodate welding operations.
• Observe the NDT services.
• Resume welding operations only after successful NDT requirements have been met.
• Contact the engineer immediately if NDT results warrant a repair or replacement plan.
• Secure all NDT reports for project QC documents. Note NDT activities on QC documents.

Visual Testing Responsibilities after Welding and Fabrication Work

Final Weld Appearance

• Inspect the finished weld.
• Use inspection tools, including a flashlight and a magnifying glass. Look for surface continuity in both the weld and the base metals.
• Focus on quality.
• Examine the weld profile and other visible features. Investigate any discontinuities such as sharp edges or undercuts.
• Evaluate the weld in accordance with the applicable code that describes the permissible amount of certain types of discontinuities. See AWS D1.1:2020, Table 8.1, Visual Inspection Acceptance Criteria, unless project specifications reference another requirement. Document the inspection on the QC drawings.

Final Weld Sizes and Lengths

• Use the project drawings and specifications to verify weld sizes and lengths.
• Inspect welds for size using a fillet gauge, bridge cam gauge, machinist’s rule, or other precision tools.
• Aid this inspection with a flashlight and a magnifying glass.
• Verify fillet weld features such as leg, toe, and throat length.
• Verify groove weld features such as cross section and reinforcement. Consider any weld size requirements noted in the project drawings or specifications.
• Consult the latest edition of AWS D1.1 to define standard weld sizes when project drawings and specifications do not specify.
• Inspect weld lengths, staggers, spacing, and openings with a machinist’s ruler, flashlight, and magnifying glass.
• Verify that all weld lengths and associated separations conform to the project drawings and specifications.
• Verify that welds noted as continuous are made as such.
• Verify that weld sizes are continuous throughout the lengths.

Dimensional Accuracy of Completed Weldment

• Use the project drawings and specifications to verify the accuracy of the finished welded project.
• Verify center-to-center, outside-to-outside, inside-to-inside, k-angles, and other noted dimensions with a steel tape measure, machinist or engineer ruler, angle finder, protractor, or other precision measuring devices.
• Evaluate alignment, level, and flushness of joined members.
• Check whether any shrinkage, distortion, bending, or buckling resulted from the welding.
• Check the relationship of any bolted, machined, or other prepared members to the welded members.

Evaluate the overall quality of the finished product.

Production Test Samples

• Check the project drawings and specifications for requirements on work sampling.
• Comply with any required work sampling.
• Prepare specimens for NDT or destructive testing.
• Work with an ASNT SNT-TC-1A or appropriate laboratory for such examination or testing.
• Observe testing whenever possible. Request records and certificates for project QC documents.
• Contact the engineer if there are any problems with the examination or testing of such work samples.
• Test Results
• Review examination, inspection, and test records for project welding operations and inspections.
• Verify that all of the required tests were performed and documented. Evaluate the results of both the required tests and visual inspections.

Final NDT Requirements

• Use the project drawings and specifications to determine the NDT requirements of the final product, such as magnetic particle testing.
• Contract, schedule, and work with an ASNT SNT-TC-1A certified laboratory to complete these requirements.
• Assist NDT technicians in the execution of NDT services. Witness examination and testing whenever possible.
• Report any issues to the engineer. Request records and certificates for the project QC documents.
• Records and Reports in Project QC Documents
• Compile project reports, including inhouse visual inspection records, contracted NDT reports, material records, filler metal certificates, welder certification reports, equipment calibration certificates and inspections, and all other documentation on project welding operations and inspections.
• Check all records for completeness and accuracy.
• Verify that any repairs or rework has been documented.
• Verify that any changes or modifications to the work have been approved and documented.
• Complete any required final inspection reports, final inspection certificates, or other closing documents.

Organize this complete content for project QC documentation.