Term
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Definition
| an interruption of the typical structure of a weldment. (may or may not be a defect) |
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Term
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Definition
| a discontinuity or imperfection that renders a part of the product or the entire product unable to meet the minimum standards or specifications. |
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Term
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Definition
| trapped gas pockets in the weld as it is being made. |
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Term
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Definition
| improper technique or contamination |
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Term
| Why could porosity be hard to detect? |
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Definition
| it can be beneath the surface of the weld. |
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Term
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Definition
| Foreign matter trapped in the weld metal. |
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Term
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Definition
| Improper/inadequate cleaning of slag between welds. |
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Term
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Definition
| Narrow breaks that occur in weld or base metal caused by localized stresses exceeding the strength of the metal. |
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Term
| Types of Weld Metal Cracks... |
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Definition
| transvers, longitudinal, crater |
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Term
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Definition
| run across the face of the weld and may extend into the base metal. |
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Term
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Definition
| usually located in the center along the length of the weld. |
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Term
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Definition
| usually occur at the ends of the weld and can lead to longitudinal cracks. |
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Term
| Incomplete joint penetration |
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Definition
| filler metal fails to penetrate and fuse with an area of the weld joint. |
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Term
| Causes of incomplete joint penetration |
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Definition
-electrode too large
-travel speed too fast
-welding current too low |
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Term
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Definition
| failure of a weld to fuse layers of weld metal and /or base metal. |
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Term
| Causes of incomplete fusion |
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Definition
-insufficient heat
-electrode size and type
-improper metal prep
-improper joint design |
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Term
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Definition
| Groove metal into the base metal beside the weld. The result of the arc removing more metal from the joint face than is replaced by weld metal. |
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Term
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Definition
-welding technique
-current too high
-arc length too long
-incomplete fill from electrode |
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Term
| Welding Procedure Specifications |
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Definition
| define and document in detail the variables involved in welding certain base metal. |
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Term
| Information included in Welding Procedure Specifications- (WPS) |
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Definition
-base metals to be joined
-filler metal to be used
-range of pre and post heat treatment
-machine settings |
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Term
| Procedure variables identified as |
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Definition
| essential or nonessential |
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Term
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Definition
| items that cannot be changed in the WPS without requalification of the procedure. |
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Term
| Examples of essential variables |
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Definition
-filler metal classification
-material thickness
-joint design
-type of base metal |
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Term
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Definition
| items that may be changed within a range identified by the code, but do not affect the qualification status. |
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Term
| Examples of nonessential variables |
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Definition
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Term
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Definition
| inspection methods that allow materials to be examined without changing or destroying them. |
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Term
| Methods of nondestructive testing |
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Definition
-visual inspection
-liquid penetrant inspection
-magnetic particle inspection
-radiographic inspection
-ultrasonic inspection
-electromagnetic inspection
-leak testing |
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Term
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Definition
-most commonly used
-fastest and most inexpensive
-majority of discontinuities and defects can be detected. |
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Term
| Pre-weld visual checks / inspections include- |
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Definition
-proper cleaning
-joint prep and dimensions
-welding procedure and machine settings |
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Term
| Post-weld visual checks/inspections include |
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Definition
-quality of root pass and succeeding layers
-sequence of weld passes
-interpass cleaning |
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Term
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Definition
| may be used to further examine defects or discontinuities in the weld. |
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Term
| Types of visual inspection gauges |
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Definition
-undercut gauge
-butt weld reinforcement gauge
-fillet weld blade gauge set |
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Term
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Definition
| penetrating liquid with use of a developer that draw out surface imperfections. |
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Term
| Advantages of liquid penetrants |
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Definition
-can detect small defects
-inexpensive
-easy to use |
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Term
| Disadvantages of liquid penetrants |
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Definition
-relatively time consuming
-can only find surface defects
-surface irregularities can hinder outcomes |
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Term
| Magnetic Particle Inspection |
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Definition
| Particles group together around defects, detecting surface cracks, non-fusion, porosity, and slag inclusions. CANNOT bye used on aluminum |
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Term
| Advantages of Magnetic Particle Inspection |
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Definition
-faster than liquid penetrant
-can detect very small imperfections |
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Term
| Disadvantages of Magnetic Particle Inspection |
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Definition
-rough surface may interfere with result
-usually requires a trained eye for proper detection. |
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Term
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Definition
| use of Xrays to examine welds, producing visual images of weld discontinuities on the weld and below the surface of the weld. |
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Term
| Advantages of Radiographic Inspection |
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Definition
-visual of entire thickness can be examined
-can be used on all types of metals |
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Term
| Disadvantages of Radiographic Inspection |
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Definition
-slow and expensive
-can be hazardous |
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Term
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Definition
| use of sound wave and vibration to examine welds. Waves pass through material and are reflected back by density change caused by a defect. |
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Term
| Advantages of Ultrasonic Inspection |
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Definition
-full depth examination
-nonhazardous
-can check materials that can't be radiographed |
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Term
| Disadvantages of Ultrasonic Inspection |
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Definition
-skill needed to properly interpret patterns
-expensive |
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Term
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Definition
| used to test tanks and pipe vessels for air/liquid containement under pressure. They can be immersed in water with soap bubble solution to detect leaks. A vacuum method can be used to extract all air from tank when only one side of tank is accessible. |
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Term
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Definition
| form of testing that destroys the weld to confirm the limits of non-destructive tests. Once information has been confirmed, non-destructive exams can be made on similar welds to locate discontinuities. |
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Term
| Destructive Tests include |
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Definition
-tensile
-hardness
-impact
-soundness |
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Term
| Soundness testing includes |
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Definition
-Bend
-Nick Break
-Fillet Weld Break |
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Term
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Definition
| Is the most common soundness test, where the test sample is bent at the weld line in a special device 180 degrees then inspected for any weld defects. Can be bent in a special jig or manual bender |
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Term
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Definition
| used primarily in the pipeline industry, when a specimen is sawcut is a specific area for specific break area then examined for defects. |
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Term
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Definition
| Fillet weld on one side of T-joint, not a strength test but intended for weld inspection. |
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Term
| Welding Position Qualifications |
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Definition
| Qualification tests are designed to measure the welders ability to make groove and fillet welds in different positions on plate, pipe, or both in accordance with the applicable code |
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Term
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Definition
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Definition
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Definition
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Definition
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Term
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Definition
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Term
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Definition
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Term
| AWS Structural Steel Code |
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Definition
| provides data re: qualifications of procedures used in structural applications. |
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Term
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Definition
| consists of "V" groove type weld with metal backing in the 3G and 4G positions |
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