TinnerFlow™Why is flat-oval duct deforming on a flat Unistrut support
3rd YearHangers, Supports & AnchorsCheck first
Flat-oval needs support that respects its shape. A flat bar can distort the flat span if the duct is wide/heavy.
Plain-English answer
Flat-oval duct has broad flat faces. If the support does not cradle it correctly, the bottom panel can sag and the internal air shape changes.
Check the duct profile, weight, support spacing, and approved support detail. Recovery may be shaped saddles, wider bearing, isolation pads, internal support, or a revised hanger layout.
Ask Foreman
The flat-oval duct at [location] is sagging across the trapeze bar. I checked the support contact and shape. Do you want a shaped saddle/wider cradle or internal support detail?
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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