Static field route #19607

What do I do when a drive cleat pops off the tight inside throat of a 45-degree elbow?

Rectangular Duct Assembly: S-and-Drive✅ LEARN / STANDARD FIXField answer expansion

📖 Verified core answer

The inside throat of an angled fitting can be under tension. Align and clamp the flanges before driving the cleat, and trim/detail only as approved.

Open in Field Rescue Open category

Field verification checklist

Check whether flanges are aligned and seated.
Look for the drive bottoming out at corner seams.
Clamp the throat joint flat before driving.
Check cleat length and end clearance.
Seal only after the drive is mechanically seated.

Ask foreman

The drive cleat is popping off the inside throat of this 45 elbow. I can clamp the flanges flat and reset the cleat, but it may need a small approved trim. Do you want me to correct it now?

Text to foreman

Route options

A Correct it only if the fix is within your assignment and approved method.

B Hold and document if it affects pressure class, listed assembly, material spec, support load path, fire barrier, equipment, TAB, or another trade.

C Bring the foreman/detailer the location, what you checked, and what decision you need before sealing, testing, cover, or startup.

Do not do this

Do not beat a drive cleat until it buckles and leaves the throat joint loose.

Why this matters

A popped drive cleat leaks, rattles, and can open up when the system starts.

Final verification

Use this as field training guidance. Final direction still comes from the foreman, approved drawings, project specs, manufacturer installation instructions, employer safety policy, pressure/material schedule, and AHJ/code requirements.

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