Vial stoppering station: vibratory stopper bowl, vacuum-held insertion head, full or partial seating for lyophilisation, and the stopper presence and height checks behind every reject
The station on a vial filling line that takes rubber stoppers from a vibratory bowl, holds each one by vacuum and presses it into a vial, fully or only partway for freeze-drying, and rejects any vial it cannot prove was stoppered
After a vial is filled with a sterile liquid it moves to the stoppering station, still inside the RABS or isolator. Stoppers arrive from a vibratory bowl, run down a track to the insertion head, are held by vacuum and pressed into the vial neck. For a liquid product the stopper is seated fully and the vial goes on to crimping; for a product to be freeze-dried it is inserted only partway, and the freeze-dryer shelves push it home at the end of the cycle. The station's job is narrow but unforgiving: every vial must leave with a stopper in the right position, and any vial without one must be removed. This page covers that station: feeding, insertion, the checks that drive rejection, and what happens to a partially seated stopper after the dryer.
Stoppering stations and units on pharmaceutical vial filling machines: vibratory stopper bowls and tracks, vacuum-held insertion heads and lifting platforms, full and partial (lyophilisation) seating, stopper presence and height checks and the reject path, and stopper pop-up after freeze-dryer closure. Complete vial filling, stoppering and capping monoblocks with their dosing and media fills are covered on the Pharmaceutical aseptic vial filling, stoppering and capping system page; aseptic food and beverage fillers on the Aseptic filling machine page; the stopper itself on the Pharmaceutical vial rubber stopper page; general-purpose vibratory bowl feeders for parts on the Vibratory bowl feeder page; beverage aseptic capping, filling valves, sterile chambers and surge tanks on their own pages.
CNFX editorial research · Sources checked October 13, 2026 · 3 sources
From bowl to vial: vibratory feed, vacuum hold and a lifting platform, at 50 to 400 vials a minute
Two published machine descriptions set out the same sequence. On Steriline's VFM fillers, stoppers are fed by a vibratory feeder bowl to the stoppering unit and the vials are stoppered by a vacuum-assisted pick-and-place system; the bowl's vibration generator sits in the mechanical volume below the process area. [1] On IMA's Easyfill, a vibratory bowl feeds stoppers continuously to the stoppering unit where they are held by vacuum, and a lifting platform raises each vial so the stopper is inserted, partially or fully. [2]
Editorial calculation: at 400 vials a minute the bowl and track must deliver 400 ÷ 60 ≈ 6.7 correctly oriented stoppers every second without a gap; at the 3,000 vials an hour of the smallest VFM model the figure is 50 a minute, under one a second. [1][2] Both figures are machine ratings that the makers qualify by vial size and filling system, so the station rate for a given vial is the number to confirm.
Diameter 14–54 mm; height 35–110 mm; up to 100 ml [2]
Output
VFM 50 up to 3,000/h; VFM 100 up to 6,000/h; VFM 200 up to 12,000/h; VFM 300 up to 18,000/h; VFM 300–400 continuous up to 18,000–24,000/h; series up to 400 vials/min [1]
State the vial (volume, diameter, height), stopper diameter and type (liquid or lyophilisation), target output in vials per minute, and whether the line runs in a RABS or an isolator.
02
Stopper presence, stopper height and the reject path: what the station checks on every vial
IMA lists the checks on the Easyfill stoppering unit as stopper presence and height control on the vials and a minimum-load check on stoppers in the vibratory bowl; the machine has a no vial – no fill – no stoppering control. [2] Steriline's VFM uses a sensor to detect stopper presence and rejects un-stoppered vials. [1]
Editorial note: a presence check alone cannot tell a fully seated stopper from one sitting high, and for a partially seated lyophilisation stopper the height is the set point itself, so a height check is the one that confirms the seating that was ordered. [2]
Check
Where it acts
Source
No vial – no fill – no stoppering
Stops a stopper being placed where there is no vial [2]
Vacuum-assisted outfeed starwheel diverts vials to the outfeed belt or a reject belt with sensors for maximum load and reject verification [2]
IMA
Ask which checks are fitted (presence, height, bowl level), how a failed vial is removed and verified, and whether rejects are counted and recorded per batch.
03
After the freeze-dryer: closing at 0.5–0.9 atm nitrogen and the stoppers that pop up before capping
Lighthouse Instruments explains what happens to partially seated stoppers at the end of the cycle: the freeze-dryer chamber is backfilled with nitrogen to the pressure specified for the vial headspace, the shelves are lowered to seat the stoppers, and closure integrity is established but not complete until the aluminium seal is applied. [3]
The note gives partial vacuum of 0.5 to 0.9 atm of nitrogen as the stoppering pressure for freeze-dried products, with some sealed under full vacuum (0 atm absolute); the vacuum helps seat the stopper and eases reconstitution. Between shelf closure and capping, minutes to days later, stoppers can pop up through improper seating during shelf lowering, out-of-specification stopper or vial flange dimensions, or stopper coatings. [3]
The consequences listed are a rise in headspace pressure that can hinder reconstitution, oxygen and moisture ingress into sensitive products, and loss of sterility assurance. [3] Editorial note: the partial-seating height set at the stoppering station, and the stopper and vial flange dimensions it is set for, are the station-side inputs to that later closure.
For lyophilised products, give the partial-seating height required, the stopper design, and the vial flange tolerance, and agree how stopper height is verified before and after the freeze-dryer.
04
What to send for a vial stoppering station
Paste it into your enquiry below or into an email to a maker, then replace every bracket.
Vial: [volume; diameter; height; flange]
Stopper: [diameter; liquid or lyophilisation design; supplied ready-to-use or washed]
Output: [vials per minute]
Seating: [full; partial height for freeze-drying]
Checks: [presence; height; bowl level; reject verification]
Barrier: [RABS or isolator; decontamination method]
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Compiled and source-reviewed by the CNFX editorial team.
Each manufacturer above links to the page on that company's own website where the product is listed, with the date we checked it. How we source and review
· Page last updated 13 October 2026
Buyer questions
How are stoppers fed and inserted into vials?
On IMA's Easyfill and Steriline's VFM fillers, a vibratory bowl feeds the stoppers, a vacuum holds each one at the stoppering unit, and it is inserted fully or partially as the vial is raised or the head descends. [2][1]
What stopper sizes does a vial stoppering station handle?
Steriline lists 13, 20, 28 and 32 mm stoppers for its VFM series, on 2 to 100 ml vials at up to 400 vials per minute. [1]
What is stopper pop-up?
Lighthouse Instruments describes stoppers rising after the freeze-dryer shelves seat them and before capping, through poor seating, out-of-specification stopper or flange dimensions, or coatings, letting gas into the vial. [3]
Sources and what still needs a direct check
Sources checked 2026-10-13. Three sources: Steriline's VFM vial filling machine brochure (2017), IMA Life's Easyfill filling and stoppering machine brochure (2024), and Lighthouse Instruments' application note on stopper pop-up in freeze-dried vials.
