What the YFL-40 Is — and What It Is Not
The Round Flange Forming Line YFL-40 is a complete ring-production line for round and spiral duct: it takes steel strip, rolls it into a flange ring, closes the joint by welding, and cuts the finished ring off the strip — automatically, in one pass. Published figures for the machine: flange diameter 100–1600 mm, material angle steel or flat steel, adjustable speed, 5.5 kW, process flow Feed → Form → Weld → Cut, list price around $18,000.
It is not a TDF or TDC machine and it does not touch rectangular duct. The YFL-40 forms the separate rings that bolt over the ends of spiral tube — the same rings used on industrial dust collection, kitchen exhaust and any system that calls for a service-removable, gasketted round joint. If your work is rectangular commercial duct, you need a TDF flange former, not this line. And if you only want a flange rolled onto the tube end itself rather than a separate ring, that is a spiral duct flanger — a different, cheaper machine. The YFL-40 sits at the top of the ring-making range: the base round flange forming line shares the same four-stage concept at a lighter duty rating.
Published Specs vs Factory Datasheet — Read Both
Two sources publish numbers for the YFL-40 and they do not fully agree, which is normal in this industry and worth understanding before you order tooling.
| Parameter | Vendor catalog figure | Factory datasheet figure | Practical note |
|---|---|---|---|
| Model | YFL-40 | YFL-40 | Same platform, both sources CNC-controlled |
| Forming diameter | 100–1600 mm | 230–1800 mm | Tooling-dependent — confirm the range that ships with your quote |
| Processing thickness | — | 1.5–4 mm | Covers angle iron grades common on industrial round duct |
| Strip width combinations | — | 15/30, 20/30, 20/40, 25/40, 30/40, 40/40 mm | Flat-leg/angle-leg widths; pick the combination at order time |
| Feed speed | Adjustable | 1–8 m/min | Real output follows ring diameter, not headline speed |
| Main motor | 5.5 kW | 5.5 kW brake motor | Plus a 4 kW hydraulic oil pump motor on the welded build |
| Control | PLC | Panasonic PLC, Schneider contactors | Brand-name electrics simplify local servicing |
| Drive | — | R-series hard-toothed gear reducer | The component that decides long-term forming accuracy |
| Footprint | — | Main 4300×800×1500 mm + decoiler 1400×700×1000 mm | Plan a straight material run of roughly 6 m |
| Weight | — | ~3000 kg | Real machine, real foundation — check your floor slab |
Where the two sources disagree, the honest reading is "build dependent": the diameter range depends on which roll tooling set is fitted, and the exact electrical specification depends on the build batch. Get both confirmed in writing on the quotation before paying a deposit.
How the Line Makes a Ring
Feeding and tension
Strip leaves the decoiler into the forming head. Tension is the setting that decides everything downstream: inconsistent tension changes springback after the rolls, and springback is what moves ring diameter. On a 3000 kg line with a hard-toothed reducer and a brake motor, the feed is stiff enough for 4 mm angle — which is exactly why the tension set-up card matters.
Roll forming
The rollers close the strip progressively into a circle. Forming tooling is cut for a diameter range — a line set up for 200–600 mm rings will not produce clean 1000 mm rings, and forcing it damages the tooling. When you quote your machine, list every diameter you sell, not just your median size, and confirm each range has tooling.
Closing the joint
The integrated welding station closes the open ring. Rings can also be joined by a connector or a clamp on lighter work, and the end preparation differs for each method — a welded ring needs square ends, a clamped ring needs exact length. Getting end preparation wrong for the joining method produces rings that cannot be assembled on site even though the forming was correct.
Cutting
The shear parts the finished ring from the strip. Cut length is the second measurable: a ring can be perfectly formed and still the wrong length, which shifts the bolt pattern. Check cut length on the first and last piece of every batch and lock the length stop.
Choosing the Strip Combination
The datasheet's width combinations — 15/30 up to 40/40 mm — are not decoration. They are the flat-leg and angle-leg widths the tooling can form, and they map directly to the joints you fabricate:
- Light commercial spiral duct: 15/30 or 20/30 combinations keep ring weight and cost down on 0.5–1.0 mm tube
- Standard industrial round duct: 20/40 or 25/40 gives enough leg for bolt holes on 1.5–2.5 mm angle
- Dust collection and heavy industrial: 40/40 at the top of the 4 mm envelope, where the hard-toothed reducer and brake motor earn their keep
One warning that applies at every width: changing coil supplier or gauge changes springback, and springback moves ring diameter. Re-set the line whenever the material changes and keep one set-up card per supplier so the changeover is a lookup rather than an experiment.
Diameter Control and Set-Up Discipline
A round flange that is 2 mm out of diameter will not bolt up on site, and the error is invisible until assembly. The YFL-40's CNC control holds what you set, but what you set has to be right:
| Check | Method | Target |
|---|---|---|
| Roundness | Measure diameter at three points around each ring | Spread ≤1 mm before the batch continues |
| Cut length | First and last ring of every batch | Within drawing tolerance, length stop locked |
| Bolt pattern | Gauge a punched ring against the connection drawing | Hole pattern matches — punching is a separate spec item |
| Tension | Stabilise before touching roll geometry | Most "roll faults" are tension faults |
| Material change | Re-set and record on a per-supplier card | Springback follows the coil, not the machine |
Give operators a diameter gauge and the authority to stop the line: a ring that looks correct can be 3 mm out, and three measurements per ring on the first and last piece of each batch catches the trend before the batch reaches site.
Common Faults and Fixes
| Symptom | Most likely cause | Fix |
|---|---|---|
| Ring diameter varies around the circumference | Strip tension inconsistent | Set and stabilise tension first, re-measure at three points; adjust rolls only if tension is proven stable |
| Diameter correct but length wrong | Cut length setting drifted | Re-set and lock the length stop; check first and last piece per batch |
| Ring will not bolt up on site | Diameter tolerance or wrong bolt pattern | Measure at three points; check hole pattern against drawing before blaming the machine |
| Springback changed after material change | New coil has different yield characteristics | Re-set for the material, record per-supplier set-up cards |
| Surface marking on formed rings | Roll damage or debris | Clean rolls with a brass brush; inspect strip edge; never steel-on-roll |
| Line stalls on heavier gauge | Tooling rated below the actual thickness | Micrometer-check the strip against tooling spec; do not force it |
Factory Acceptance Checklist
Work this list at commissioning — it is short, measurable, and it protects the invoice:
- Form, weld and cut test rings at 1.5 mm, your median gauge and the full 4 mm
- Three-point diameter on every test ring; record the spread (≤1 mm target)
- Cut length across a ten-ring batch at your largest production diameter
- Bolt-hole pattern check against your connection drawing
- Confirm in writing which diameter ranges and strip-width combinations ship with the machine, and price the rest
- Run one full material changeover and sign off the set-up card procedure
- Section a welded test ring and inspect penetration
- Verify Panasonic PLC and Schneider electrical components against the quotation build list
FAQ
Why do the catalog and datasheet diameter ranges differ?
Because the range is a property of the roll tooling, not the frame. The catalog's 100–1600 mm and the datasheet's 230–1800 mm are both achievable builds; what matters is which tooling set is on your quotation. Confirm it in writing and demo-form a ring at each end of the promised range during acceptance.
Can it make both angle rings and flat-strip rings?
Yes — angle steel and flat steel are both within the material specification, with the roll sets chosen at order time. Shops that supply clamp-together light commercial duct alongside bolted industrial rings typically buy both sets.
What output should I plan per shift?
Ring count follows diameter, because rolling time follows circumference. Small rings cycle in well under a minute; 1200 mm-class rings take several. Ask the factory to quote production rate at your top three selling diameters during the technical clarification — that number, not the headline 8 m/min, is what sizes your investment.