Welding/welding wps

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Question
Dear Sir,
Regarding WPS, I have doubts regarding bend tests. In Sec IX for thickness between 1.6 to 10mm it was mentioned to conduct (2 tensile,2 face,2 root bend) tests. It was mentioned both transverse bend and longitudinal bend tests. How to select which type of test(transverse bend and longitudinal bend) to be conducted on test coupon for procedure qualification and also for performance qualification Or Is it necessary to conduct both type of bend tests
Test conducted on 300x300x5mm sample (150x150 samples 2).For performance qualification bend test can be substituted with radiography .But for procedure qualification which type of bend test to be conducted

Answer
The Root Bend and Face Bend combination is common for thinner steel thicknesses.
For heavier thickness materials we use Side bends, because you get the root and face at the same time.

Transverse bends give you the best chance of opening a flaw in the surface of the root or face.

Longitudinal bend tests are rarely used, because they don't demonstrate the flaws as well, but they will demonstrate the ductility of the heat affected zone.
However Longitudinal All-Weld-Metal Tensile tests are used to demonstrate ductility and strength of the weld metal.

Which tests are required is up to the discretion of the person drafting the Procedure, unless an engineer has specified a preference.

Being a Certified Weld Inspector often means using your judgment to make decisions.
Not everything is handed to you.
Often you are the highest authority on a jobsite.
Only the Engineer has a higher authority, and they often know less about welding.

When deciding what tests to use to either qualify a procedure or a welder, you have to ask some questions.
Is the test effective at demonstrating weld flaws?
Is the test appropriate for materials or conditions?
Is the test practical to complete with existing equipment and personnel?
Is a destructive or non-destructive test better for this application?

Remember that a destructive test is a one time event with that sample.
A non-destructive test can be repeated to verify results.

When I became a CWI I had little preparation for what the job entails in industry.
As a CWI you are expected to know everything about the work being done, or at least know who to ask.

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Ernie Leimkuhler

Expertise

Questions about Oxy-Acetylene welding/cutting, MIG, TIG, Flux-core, Stick welding, brazing and soldering, bike frames, air frames, motorcycle frames, structural welding. Also questions about Welding Certifications and Inspections. All questions about fabrication of metals (stainless steel, steel , aluminum, brass, bronze, copper). Basic questions about underwater welding. TIG is my strongest subject.

Experience

Extensive background in most welding fields. 18 years fabrication of metal theatre scenery, 16 years structural steel, 2 years pipe welding, 9 years as a Welding Instructor at South Seattle Community College, and 5.5 years as a Welding Instructor at the Divers Institute of Technology. 16 years Industrial Welding Consultant for fabrication shops in the greater Seattle Area. 11 years Architectural Metal Fabrication. 8 years in Film/TV; SPFX/construction/set-deco/props/. 33 years Blacksmithing and Knifemaking. Currently a Field Welding Inspector for Otto Rosenau and Associates.

Organizations
American Welding Society - Certified Welding Inspector Washington Assoc of Building Officials (WABO) - Special Inspector - Structural and Reinforcing Steel.

Publications
Do a search on google groups for "Ernie Leimkuhler" in the rec.crafts.metalworking and sci.engr.joining.welding groups. http://www.stagesmith.com/ http://www.metalwebnews.com/ Blacksmith's Gazzette - Anvil Making

Education/Credentials
BA Theatre Technology - Purdue University.

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