The mainstream process for two-piece can production lines is DRD (Draw-Redraw) deep drawing without ironing.
Using tinplate / tin-free steel (TFS), this line manufactures shallow drawn cans and shaped cans (round, square, oval,
fish-shaped) with uniform wall thickness and excellent pressure resistance, ideal for high-temperature sterilization
applications. We can provide production lines of high, medium and low speeds to match different can dimensions and
customer requirements.
Process Flow
1. Material Feeding
Automatic CNC feeder continuously supplies tinplate to the entire production line.
2. Blanking
A high-speed press equipped with forming dies punches out circular blanks. The blank diameter is determined by
the can height and mouth diameter.
3. Cup Forming (Pre-forming)
Circular blanks are fed into the cup press (1–2 stations) to form shallow cups with an outer diameter close to the finished can. The cup height ranges from 25 mm to 40 mm with a slightly domed bottom for pre-forming.
4. Multi-stage Deep Drawing (Core DRD Process)
Shallow cups proceed to a 2–4 stage tandem deep drawing press:
· 1st drawing: The cup diameter is reduced and height increased while the wall thickness remains unchanged.
· 2nd to 3rd drawing: Further diameter reduction and height increase until the final can height is achieved.
· Final stage: Can bottom forming with anti-slip patterns and pressure-bearing rings. The pressure resistance reaches no less than 6 bar.
5. Trimming
The uneven can mouths after deep drawing are trimmed by a rotary trimmer. A margin of 3–6 mm is cut off to keep the can height tolerance within ±0.15 mm.
