Strengh of Weld Cap

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Hi all,If we remove the weld cap (make it the same level with base metal, can we say the strength of the weld is almost the same as the base metal? From my understanding, by having weld cap, the weld will have higher strength compared to the base metal.
Reply:need more info.  Is this cap on pipe? Was it professionally welded and inspected?Lincoln MK 250, Syncrowayve 351, Cutmaster 151, SA 250D, bobcat 225  and want more.4 Daughters, 6 cats, 1 dog, 1 wife and don't want anymore.
Reply:On steel when you grind the cap if its properly welded, yes it should be ok. The rod metal is stronger than the parent metal. With aluminum, no. When aluminum is welded the weld metal is weaker than the parent metal, so its probably better to leave some cap for reinforcement.Nothing Ever Got Done By Quitting, Never Give Up.
Reply:Originally Posted by Doug247 With aluminum, no. When aluminum is welded the weld metal is weaker than the parent metal, so its probably better to leave some cap for reinforcement.
Reply:HAZ is the weakest part on most ally weldments, not filler material.
Reply:Originally Posted by Doug247On steel when you grind the cap if its properly welded, yes it should be ok. The rod metal is stronger than the parent metal. With aluminum, no. When aluminum is welded the weld metal is weaker than the parent metal, so its probably better to leave some cap for reinforcement.
Reply:......Last edited by RodBender; 04-11-2014 at 09:37 PM.Reason: Double post. Please delete. Thank you.Local 83
Reply:By leaving a joint with a really high and wide cap, or thick reinforced root, it doesn't necessarily make the welded joint any "stronger". If the cross sectional area of weld is larger/thicker/wider than the parent metal it just makes the parent metal the weak link. Especially if there is undercut at the edges or a defect like porosity/incomplete fusion/embrittlement. I weld pipe and the reason why the inside root and cap have an 1/8th inch limit on reinforcement is because making the joint larger/taller wastes time, material, and creates more friction inside the pipe. It does strengthen or improve the joint. But if it is shallower than the parent metal it is weaker.Local 83