X-ray fill-level checking
Measures the product region through the can and can be configured for low, high or grossly missing fills.
Fill-level inspection ›
Opaque container inspection
Can Fill Level Inspection Systems UK
Inline underfill, overfill and missing-fill checks for beverage cans and other opaque metal containers, with line tracking and automatic rejection.
Direct answer
How is fill level checked through a metal can?
Because visible-light cameras cannot see through metal, can fill level is normally assessed using a penetrating or indirect method such as X-ray, high-frequency sensing or checkweighing.
The right method depends on the can, product, foam, target tolerance and line speed. Each result is compared with the active recipe, then the can is tracked to a reject point if it falls outside the permitted window.
Method selection
Choose the signal that remains stable in production.
A can is opaque, but its contents can still be checked. Representative filled, low-filled, high-filled and borderline samples establish which method gives the clearest separation.
High-frequency sensing
May provide a compact non-contact level check where the container and product create a repeatable response.
Checkweighing
Verifies total pack mass when net content matters more than the physical height of the product in the can.
Canning-line specification
Control the variables around the measurement.
The inspection position, can stability and product condition matter as much as the sensing head. The application brief should include the real production envelope.
- Can material, diameter, height, end type and all planned formats
- Product density, carbonation, foam, suspended solids and settling behaviour
- Nominal fill, permitted low and high limits, and borderline samples
- Line speed, pitch, conveyor vibration, guides and space after the seamer
- Reject type, reject confirmation, bin control and line-stop requirements
- Recipe control, counters, trends, alarms and filler or PLC interfaces
Checks around the fill
One controlled station can protect more than net content.
Where the sensing and camera views are compatible, the fill decision can be coordinated with other full-can quality checks.
Practical answers
Questions from canning teams.
Final performance and inspection limits are confirmed using representative cans at the required production conditions.
Ask an engineerCan a normal vision camera inspect through an aluminium can?
No. Visible-light cameras can inspect the exterior, code, lid and shape, but they cannot see the fill boundary through metal. X-ray, high-frequency sensing or weight-based inspection is assessed for the contents.
Can one system inspect several can sizes?
Yes where the sensor range, conveyor handling and reject arrangement cover those formats. Validated recipes store the correct inspection region and acceptance limits for each can and product.
Where should can fill inspection be installed?
It is commonly placed after filling and closure where the product condition is repeatable and there is enough controlled conveyor length for sensing, tracking and rejection. The exact point is agreed from line layout and process behaviour.
Can the system feed fill trends back to the filler?
It can provide counts, trends and alarms, and may support controlled feedback where the filler, inspection method and line controls provide a suitable interface. The feedback strategy must avoid correcting normal short-term variation.
Talk to Oxford Vision Systems