TinnerFlow™Why do round slip joints need uniform crimps
1st YearDuct Assembly, Seams & JointsField Reference
Round slip joints need an even crimp around the full pipe end. Shallow random dents will not give the fitting a solid mechanical bite.
Plain-English answer
You are prepping round pipe joints on the ground by crimping the raw end of a cut pipe to make it fit into an elbow collar. You use a single-point hand crimper and make shallow, uneven dents that slip right apart under pressure.
Round slip joints need an even crimp around the full pipe end. Shallow random dents will not give the fitting a solid mechanical bite. The likely recovery is to check the condition, correct prep/setup if it is within your assignment, and bring the foreman clean information before the work creates rework overhead.
Ask Foreman
Those shallow dents won't hold under system pressure. Use the 5-blade crimpers to make deep, uniform folds an inch and a half deep around the rim so the pipe slides home snug into the fitting.
Verify before acting
Use this as training guidance. Foreman direction, approved drawings, project specs, manufacturer instructions, employer safety policy, and AHJ/code requirements always control the final answer.
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