Packaging Machinery · Equipment category

Inspection Systems

Quality control machines that detect contaminants, verify weights, and check seal integrity.

Best for
Food safety compliance, pharmaceutical regulations, and brand protection.
Common formats
Metal detection, X-ray imaging, checkweighing, vision systems.
Metal detector conveyor inspecting packaged products on a production line

Inspection is not one machine

Inspection systems are the last check before a package leaves the line — and they answer different questions. A metal detector finds ferrous and non-ferrous metal; an X-ray system finds metal, glass, stone, bone and dense plastics by density; a checkweigher verifies weight; vision checks the label and visible defects. Choosing the right one starts with naming the risk you are actually trying to catch.

The technologies

Metal detection passes the package through a balanced electromagnetic field; X-ray measures density and flags anything denser than expected; checkweighing weighs every package in motion against legal or cost tolerances. A conductive product such as meat, cheese or brine defeats a basic metal detector and pushes you toward X-ray or a product-compensated detector.

Selection factors that decide the system

  • What you are catching: metal-only, or also glass, stone and bone?
  • Product conductivity: conductive products change the metal-detector choice.
  • Weight compliance: regulated fills need a checkweigher against the destination market’s framework.
  • Where in the line: after sealing catches upstream contamination; before sealing may be needed for some products.

Choose the supplier on demonstrated sensitivity

Start with the Top 10 Product Inspection System Manufacturers ranking, and see How Product Inspection Systems Work for the principles. Ask each supplier to detect a known test contaminant on your product at line speed before you buy.

Decision guides

Start with this guide

in-line-vs-standalone-inspection
Compare
In-Line vs Standalone Inspection

The core idea of this page: in-line inspection sits on the production line and checks every pack at speed; standalone inspection is an offl...

Jul 29, 2026 · 2 min read
checkweighing-vs-metal-detection
Compare
Checkweighing vs Metal Detection

The core idea of this page: a checkweigher catches under/overfill by weighing every pack; a metal detector catches metal contamination. The...

Jul 14, 2026 · 2 min read
metal-detection-vs-x-ray-inspection
Compare
Metal Detection vs X-Ray Inspection

The core idea of this page: a metal detector finds metal only; an X-ray finds metal plus glass, stone and bone by density. Choose by the co...

Jun 30, 2026 · 2 min read
Top companies

Featured manufacturers

Company Ranked #1
Mettler-Toledo

Swiss manufacturer of product inspection systems, including Safeline metal detection, checkweighing and X-ray inspection.

Jun 11, 2026
Company Ranked #2
Thermo Fisher Scientific

Product inspection: Sentinel metal detection, Versa checkweighing, NextGuard X-ray.

Mar 28, 2026
Company Ranked #3
Ishida

Japanese manufacturer of VFFS bagmakers (INSPIRA, ATLAS series) and multihead weighers, founded in 1893.

Sep 27, 2025
Company Ranked #4
Loma Systems (ITW)

Metal detection, checkweighing and X-ray builder (IQ4, CW3, X5).

Apr 16, 2026
Company Ranked #5
Anritsu Infivis

Metal detection, checkweighing and X-ray with dual-frequency technology.

May 5, 2026
Company Ranked #6
Bizerba

Checkweighing, metal detection, X-ray and vision inspection.

May 23, 2026
Company Ranked #1
Techik Instrument (Shanghai)

Leading Chinese inspection equipment maker spanning metal detection, checkweighing and X-ray.

Sep 1, 2025
Company Ranked #3
Unicomp Technology

Chinese industrial X-ray and CT inspection equipment maker.

Oct 28, 2025
Company Ranked #4
Mesnac

Listed Chinese machinery maker with tire X-ray inspection systems.

Nov 15, 2025
Featured products

Representative equipment

Technical reference

Knowledge

Frequently asked questions

Common questions

What is the difference between metal detection and X-ray inspection?
A metal detector finds ferrous and non-ferrous metal by disturbing a balanced electromagnetic field. An X-ray system finds metal, glass, stone, bone and some dense plastics by density difference, and can also check completeness and mass. X-ray inspects the conductive products that defeat basic metal detectors.
Do I need a checkweigher?
If the fill weight is regulated, a checkweigher is not optional — it verifies every package against the destination market's framework, such as the EU MID / OIML R51 and WELMEC 6.5, or NIST Handbook 44 in the US. Even without regulation, it prevents product giveaway.
Why does inspection sensitivity depend on the product?
Conductive products such as meat, cheese and brine are harder to inspect with a metal detector than dry foods. X-ray depends on density rather than conductivity. Always test detection sensitivity on your actual product and packaging, not a reference sample.
Where should inspection sit on the line?
Inspection after sealing catches contamination introduced upstream; inspection before sealing may be needed for product that is then sealed. The point is chosen against the risk you are trying to catch and the reject-and-remove workflow you can support.
What is the false-reject rate, and why does it matter?
The false-reject rate is how often good product is wrongly rejected. An over-tight detector rejects good product and erodes operator trust, so sensitivity must be specified together with the false-reject rate on your actual product.
How is detection sensitivity measured?
Sensitivity is quoted as the smallest metal sphere (e.g. Fe Ø0.5mm, SUS Ø1.0mm) or the smallest X-ray-visible foreign body. It is aperture-dependent and must be validated on your product and packaging, not a dry reference sample.
Do I need X-ray or is a metal detector enough?
A metal detector only finds metal. If your contaminant risk includes glass, stone or bone — or your product is conductive — you need X-ray inspection. Choose by the contaminant you must actually catch.
What does a checkweigher legally require?
If you sell by weight, the checkweigher may need MID/OIML approval for legal metrology (EU) or NTEP/Handbook 44 (US). Confirm the certification for your market before buying.