Automatic Cans Filling Line

A double seam is the two-stage fold that joins the can end to the can body, forming the only barrier between your product and the outside air. It is judged externally by non-destructive visual and dimensional checks, and internally by tearing down the seam and measuring the overlap between cover hook and body hook — overlap is the critical dimension. On a line the routine matters as much as the measurement: dimensions should be recorded per seamer head on a schedule, so a trend is visible before leakers appear.

Multi-head seamers rotate and seam one can per head in sequence. If one head develops a mechanical problem (roll wear, chuck wear, timing drift or lubrication failure), only the cans seamed by that head are affected, so defects repeat at a fixed interval equal to the head count: every 4th, 6th or 8th can. Fixed-frequency sampling can therefore miss a consistently defective head entirely, because an interval that aligns with the head count may keep checking the good heads. Track seam dimensions per seamer head, not per shift.

Seam inspection should be a scheduled routine, not something triggered only by leakers. Industry practice is to tear down and measure the internal dimensions of the seam for each seamer head at a set interval during production, and to record the results so trends are visible. Because defects from one head appear periodically rather than continuously, the interval must be short enough that every head is sampled within a production run. A practical routine on this line is to tear down and measure every seamer head at the start of the run, then at least once every 30 minutes of production — every 15–30 minutes on uninterrupted high-speed runs — and again after any jam, adjustment or can/end change.

In practice this line holds the pickup to roughly 20–30 ppb at the filler, with the CO₂ pre-purge and a stable 0.3–0.5 MPa fill keeping it there. Oxygen pickup on a canning line comes mainly from the air left in the can before filling, plus turbulence at the filler, so the control is a CO₂ pre-purge plus stable isobaric filling and low foaming. Measurement should be taken at the filler head under normal production conditions; industry benchmarks put a good canning operation below 30 ppb DO pickup.

The line runs 330 ml and 500 ml cans as standard, with can heights from 50 mm to 350 mm (customizable) and the common 202 / 204 and 211 body diameters covered by the seamer change parts. Can sizes are handled by changeable format parts and seamer change parts, and a format change on a line touches several stations at once — infeed and conveyor guides, the filler, the seamer and the labeller. That is why a changeover is planned as one sequence rather than machine by machine. Send us your can formats and we will confirm the change part set.

Yes. The filling valve has a "no vacuum if no can" function, so the filler does not release product when a can is missing from the position — this avoids product loss and keeps the machine clean during gaps in the can flow. It matters most on high-speed lines, where a single missing can is a normal occurrence rather than a fault.

Yes, and on a line this is a valve-set and pressure-design decision rather than a change of machine. Carbonated products are filled isobarically with a CO₂ pre-purge to hold carbonation and suppress foaming, while still products are filled without counter-pressure. Both then run through the same conveyor, seamer, dryer and labeller. Give us the full product mix and the split between them and we will specify one valve set that covers the range.

Filled and seamed cans pass a drying machine to remove surface water, then a laser coding machine applies date and batch codes, and a labelling machine applies the label — all carried on the can conveyor system. The drying step matters because residual water interferes with both coding and label adhesion.