Auto Duct Line Comparison: SBAL-V vs SBAL-III vs SBAL-II (2026)

The spec comparison table

An auto duct line takes a steel coil in at one end and delivers finished, closure-ready rectangular duct at the other. What separates the three SBKJ lines is how much of that process happens inline in a single pass — which drives the line's power, weight and finished output. Here they are side by side.

Source: SBKJ Product Catalog 2026, manufacturer nameplate specifications. Duct conforms to SMACNA / AS NZS 4254 rectangular-duct construction. Width models are available in 1250 mm and 1500 mm variants (SBAL-V-1250J/1500J, SBAL-III-1250/1500).

Line speed is not output — read this before you compare m/min

The most common mistake buyers make reading these numbers is treating line speed as output. The entry SBAL-II runs the fastest raw line speed at 18 m/min, faster than the flagship SBAL-V's 16 m/min — yet the SBAL-V produces far more finished duct. The reason is integration: on the SBAL-V the duct comes off the line already notched, sheared, TDF-flanged and Pittsburgh-locked in a single continuous pass, so it is ready to install. On a lighter line, those operations happen at separate stations with extra handling between them, so the duct moves through the workshop more slowly overall even though one station runs quickly. Compare finished-duct throughput and operator count per square metre, not the headline m/min.

How to choose

Output target first. For a workshop targeting roughly 1,500–2,500 m² of finished rectangular duct per day with a small crew, the SBAL-V's single-pass integration pays for its higher capital and 87 kW supply. For mid-volume shops or those that already own a TDF machine, the SBAL-III delivers most of the automation at a fraction of the power and weight. For a shop adding its first automated line on a tight budget, the SBAL-II is the lowest-capital entry into coil-fed rectangular duct.

Then power and floor. The jump from the SBAL-II (5.5 kW, ~9 t) to the SBAL-V (87 kW, ~16 t) is large — confirm the electrical supply and floor loading early, because retrofitting a 3-phase feeder or reinforcing a slab after the machine arrives is expensive. SBKJ supplies a 2D workshop layout drawing with every quotation so the line, uncoiler and run-out table are sized to the available floor before you commit.

Then closure. All three lines produce TDF and Pittsburgh-lock duct, so the connection method is not the deciding factor here — the deciding factor is how much of the work you want done inline versus at separate stations. For the trade-offs between TDF and bolted angle flange, see the TDF vs angle flange reference.

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FAQ

What is the difference between SBAL-V, SBAL-III and SBAL-II?

Integration. The SBAL-V runs uncoiling, beading, notching, shearing, TDF flanging and Pittsburgh locking in one continuous pass. The SBAL-III uses hydraulic notching and shearing with a separate TDF station. The SBAL-II is the entry-level line for straightforward rectangular duct. More integration means more finished duct per pass.

Which auto duct line has the highest output?

The SBAL-V, despite its 16 m/min line speed versus the SBAL-II's 18 m/min — because it produces finished, closure-ready duct in a single pass. SBKJ rates the SBAL-V for up to about 2,500 m² of finished duct per day.

How much power and weight does an auto duct line need?

The SBAL-V draws 87 kW at ~16 tonnes; the SBAL-III 15.7 kW at 8–9 tonnes; the SBAL-II 5.5 kW at ~9 tonnes. All run 380 V, 50 Hz, 3-phase (60 Hz on request).

What gauge and width can these lines handle?

The SBAL-V handles 0.5–1.5 mm; the SBAL-III and SBAL-II handle 0.5–1.2 mm. All three form rectangular duct up to 1500 mm wide.