Single-Pass vs. Scanning Corrugated Presses: How the Imaging Method Sets Your Limits

"Single pass or scanning?" is usually the first question a converter asks when comparing digital corrugated presses. The two terms do not describe different printing technologies — both are inkjet — but two different ways of moving the printheads relative to the board. Once that clicks, the differences in width, speed and resolution stop being a spec-sheet puzzle and become predictable.

The short answer: does the head move?

On a single-pass press the printheads are fixed in a full-width array. The board travels underneath once and the entire image is laid down in a single stroke. On a scanning press the heads sit on a carriage that shuttles back and forth across the sheet, printing one band at a time while the board indexes forward between passes.

The consequence is direct: single-pass throughput is capped by how fast you can feed board, while scanning throughput is capped by how many carriage passes the image needs.

Single-pass: one stroke, whole image

Three single-pass models in the Ruisheng RS2500 range show the trade-space:

• RS2500-E72G — 72 high-precision piezoelectric heads, 1,200 mm (47.2 in) print width in high-speed mode, up to 150 m/min (492 ft/min) excluding feed time, >600 × 300 dpi.
• RS2500-E36S — 36 heads, also 1,200 mm wide, up to 106 m/min (348 ft/min) excluding feed time, >600 × 300 dpi.
• RS2500-E32S — 32 heads, 530 mm (20.9 in) wide in high-speed mode, up to 200 m/min (656 ft/min) excluding feed time, >1,200 × 150 dpi.

Set the E72G next to the E32S and the physics becomes obvious. With a comparable head count, a narrower array covers less width per pass, so more board length clears the machine every minute. The E32S trades format for line speed; the E72G spreads 72 heads across 1,200 mm and still holds 150 m/min. Asking "which one is faster?" is meaningless until you first answer "how wide are your boxes?"

All three accept board from 3–40 mm (0.12–1.57 in), covering common single-wall through double-wall grades, and all use a leading-edge auto feeder with a vacuum platform in CMYK.

Scanning: a traversing carriage, band by band

• RS2500-E16 — 16 piezoelectric heads, >360 × 1,200 dpi, auto feed up to 2,500 × 1,350 mm (98.4 × 53.1 in), manual feed 2,500 mm wide with unlimited length, up to 600 m²/h (6,458 sq ft/h) excluding feed time.
• RS2500-E8 — 8 heads, >360 × 600 dpi, 2,500 mm (98.4 in) wide with unlimited length, up to 600 m²/h excluding feed time.
• RS2500-E20UV — 20 heads, dedicated UV ink, >360 × 600 dpi, up to 90 m²/min excluding feed time.
• RS2500-R16UV — 16 heads, built for spot-colour work, >360 × 600 dpi, up to 400 m²/h excluding feed time.

Scanning is not about line speed; it is about format and resolution headroom. Because the carriage can lay down multiple passes over the same area, the E16 reaches >360 × 1,200 dpi across a 2,500 mm sheet — the right tool when the print itself is on display, such as display packaging and full-colour shipping cartons.

Three differences that get misread

1. The speed units are not comparable

Single-pass speed is quoted in m/min (linear); scanning speed in m²/h or m²/min (areal). To compare them, convert through the width: a 1,200 mm press running at 150 m/min works out to roughly 10,800 m²/h of theoretical area. That is a theoretical estimate — real throughput moves with ink coverage, resolution mode and board size.

2. dpi has two axes

>600 × 300 dpi and >360 × 1,200 dpi are not ranked one above the other; they distribute resolution differently across and along the sheet. For transit packaging built on brand marks, graphics and 1D/2D barcodes, both configurations print cleanly and scan reliably. High-resolution colour imagery and display panels are where the extra cross-web resolution earns its keep.

3. The width ceiling is structural

In single-pass, width equals the length of the head array: going wider means more heads, more ink plumbing and more cost. In scanning, width equals carriage travel, which is far cheaper to extend — which is why every 2,500 mm-class machine in the range sits on the scanning side.

One more axis: ink set is independent of architecture

Imaging method (single-pass or scanning) and ink set (water-based or UV) are two separate axes, and mixing them up is a common source of confusion. The RS2500-E72G, E36S and E32S all run dedicated water-based dye ink or water-based pigment ink: dye is brighter and costs less, while pigment holds up better against light and moisture, suiting cartons stored outdoors or shipped long distances. The scanning E20UV and R16UV run dedicated UV ink, cured instantly under UV lamps — waterproof and rub-resistant with high colour saturation, ready for finishing immediately with no drying wait.

Where moisture and abrasion resistance are hard requirements, a UV model is the direct answer. Water-based models can also improve surface performance with an optional inline drying and varnish system, available on the E36S and E72G.

Match the press to your order book

• Dominant box width within 1,200 mm, fairly standardised sizes, high daily volume — look at single-pass: E72G (1,200 mm / 150 m/min) or E36S (1,200 mm / 106 m/min).
• Wide spread of box sizes, frequent oversize or very long cartons — look at scanning: E16 or E8, 2,500 mm wide with unlimited length on manual feed.
• Narrow standardised cartons, throughput above all else — E32S, 530 mm at 200 m/min.
• Output must resist water and abrasion — choose a UV model, E20UV or R16UV; pick R16UV when brand spot-colour consistency is the priority.

That is a first-pass match on published specifications only. Coating, moisture content and flute profile all change how a board actually prints, so a sample run on your own board and your own artwork is the right next step before committing. For a recommendation against a specific box list, or for commercial terms, contact an application consultant for a proposal and a quotation.

Frequently asked

Is scanning always slower than single pass?

It depends what you measure. Single pass moves an individual board through faster. But if your format is a 2,500 mm-wide layout, a single-pass array cannot cover it in one stroke anyway. Convert both figures to areal throughput (m²/h) before comparing.

Can I start with scanning and add single pass later?

Yes. Both families run on the same professional RIP and print software, so operator training and RIP workflows carry over without starting again.

Is higher resolution always better?

Resolution usually costs throughput or ink. On transit packaging driven by brand marks, graphics and barcodes, >360 × 600 dpi already renders fine detail that scans reliably; only artwork-led and display work justifies paying for more.