Guided Bend Testing for Welder Qualification

[cjgrass]

API 1104 20th edition requires face and root bends for pipe over 12 3/4"OD, 0.500"WT and under side bends for over 0.500". We have pipe that is designated on the MTR as 16"OD x 0.500" X65 we used for testing, when measuring the tensile samples we noticed the actual wall thickness is slightly over .500", 0.537" nominal. My question is: Because the actual wall thickness is over 0.500" should we have tested side bends instead of root/face bends or go by the thickness listed on the MTR and root/face bends are correct.

 

[Duwe6]

Root/Face bends of a coupon thicker than 1/2" will give more stress and more fiber elongation; it was harder to pass this test [and harder on the bending jig]. Additionally, you seem to be getting overly precise. The concept in ASME is to switch to side bends at 3/8" and API to switch at 1/2" [bigger die radius]. These Codes do not say 0.375" or 0.5000". The pipe was nominally 1/2", so your test met the 1104 requirements.