Auto Duct Line 4 AML-4
Last updated: October 14, 2026
Auto Duct Line 4 (AML-4) adds automatic folding to the Line 3 process, reducing manual labor while maintaining a compact footprint. Ideal for medium-volume shops seeking a balance between automation and investment.
Technical Specifications
What is a Auto Duct Line 4 AML-4?
Auto Duct Line 4 (AML-4) takes the Line 3 process and adds automatic folding. Blanks are decoiled, leveled, beaded, notched, sheared and folded into rectangular duct sections automatically — removing the manual folding station that Line 3 leaves to separate machines, while keeping a footprint far smaller than a full Line 5.
Key Features
- Coil loading and decoiling with frequency-controlled motors
- Leveling and beading integrated
- Hydraulic notching (TDF and sharp notching)
- Hydraulic shearing to length
- Automatic folding station — the step Line 3 does not have
- PLC control with touch screen
Manual Folding Bottleneck After Your Blanks Come Off the Line?
Line 3 produces notched blanks faster than your team can fold and close them by hand — the folding station becomes the bottleneck, and every extra folder you hire is another wage line.
The AML-4 folds automatically in-line: the blank goes in, a folded duct section comes out. Same compact footprint as Line 3, with the manual folding labor taken out of the process.
How It Transforms Your Production Line
The Auto Duct Line 4 AML-4 works on a proven principle — here is the step-by-step workflow that makes it possible:
Coil Feeding
Coil is decoiled and fed through the leveling and beading stations.
Notching & Shearing
Hydraulic notching and shearing produce the blank to programmed length.
Automatic Folding
The automatic folding station folds the notched blank into a rectangular duct section — no hands on the panel.
Section Out
Folded sections discharge for seam closing; seam closing remains a separate station, as on Line 4.
Technical Specifications & Performance Data
Every specification on this machine is chosen for a reason. The table below shows not just the numbers, but what each one means for your daily production:
| Parameter | This Machine | What It Means for You |
|---|---|---|
| Control System | PLC with touch screen | Consistent, repeatable operation with minimal operator training |
| Construction | Heavy-duty steel frame | Vibration-free operation, 10+ year service life |
| Certification | CE certified | Meets European safety and quality standards |
| Warranty | 2 years | Peace of mind with comprehensive factory warranty |
Problems Solved: Before vs. After
We asked HVAC fabricators about their biggest production headaches. Here is how this machine directly addresses each one:
| Without This Machine | With This Machine |
|---|---|
|
✕ Manual folding bottleneck
Blanks queue at the hand-folding station |
✓ Automatic folding station
Folding runs in-line at line speed |
|
✕ Folding labor cost
Every folded section is operator wages |
✓ In-line automation
Folding labor taken out of the process |
|
✕ Inconsistent hand folds
Folded sections vary with the operator |
✓ Machine folding
Repeatable fold geometry section after section |
|
✕ Line 5 investment gap
A full Line 5 costs more than the volume justifies |
✓ Balanced automation
Line 3 plus folding, in a compact footprint |
Where It Fits in Your Factory
This machine is versatile enough to serve multiple production scenarios. Here are the most common configurations our customers use:
Balanced Investment
More automation than Line 3, less cost and space than Line 5 — the middle option.
Labor-Constrained Shops
Remove the manual folding station from your labor bill without adding a full line.
Medium-Volume Production
Sized for shops scaling past Line 3 output with folding still the constraint.
Compact Plants
Automated folding in the Line 3 footprint — no line 5 floor plan required.
Frequently Asked Questions
Click each question to see the answer. These are the questions our sales engineers hear most often:
Professional Packaging & Global Shipping
Every machine is professionally packaged and secured in a container for safe delivery to your port. We send you loading photos before the ship sails.
Calculate Your Return on Investment
Based on average industry data, here is what a typical customer saves after installing this machine:
* Figures based on average customer data for a shop producing 100-500 bends per day. Your actual results will vary based on production volume, labor rates, and current efficiency levels. Contact our engineers for a customized ROI calculation based on your specific operation.
Ready to Upgrade Your Electric Production?
Get a customized quote within 24 hours. Our engineers will help you configure the right machine for your specific production requirements.
WhatsApp / WeChat: +86-18355321923 | Email: jason@predamachine.com
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Before you request a quote: how this machine class compares, what it costs, and how to size it for your production volume.
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Read the guide →