Testing of internal threads, contactless and in real time.

The optical test system records the complete internal thread.

Generally speaking, the test is carried out over the entire thread length in 4 evaluation windows offset by 90 degrees.

The completeness and the regularity of the threads is checked.

The position and number of evaluation windows can be adapted to the respective test requirements.

Monitorbild: Auswertung eines M14x1,5 mm x 12 mm tiefen Innengewindes in einer Durchgangsbohrung. Die vier um 90° versetzten Auswertefenster decken die gesamte Gewindelänge ab.

System features

  • Real-time evaluation through intelligent CCD camera during ongoing production.
  • Integrated evaluation software on the camera, i.e., no external computer required.
  • Opto-uncoupled inputs/outputs for monitoring and control tasks for embedding in existing sequences.
  • Integrated narrow measuring head with special optics and lighting.
  • Good integratability in existing test or production systems.
  • The system detects:
    • Thread not present.
    • Thread incomplete.
    • Thread irregular (no correct thread spacing).
  • The complete thread length is recorded and scanned at regular intervals.
  • Bottoms of blind holes are checked, e.g., for cracks, chips and/or colour defects.

Example of a defective through-hole thread, M14x12mm

Gewindeflanken gar nicht oder nur zum Teil vorhanden.
Fehlerhafter Gewindegang an einem Radflansch.

Example of a blind hole with internal thread, M4x4.5mm

Sacklochbohrung für M4x4,5mm Innengewinde. Hier sind keine Gewindeflanken vorhanden: fehlerhaftes Bauteil.
Dieses Innengewinde ist in Ordnung, die Anzahl der Gewindeflanken ist korrekt.
Sacklochbohrung mit Span.

Optical test system for objects with an internal thread of M4-M6x2-5mm


  • Well known optical systems only view from the side into the bore, and may overlook defects on the thread lead-ins and run-outs.
  • The number of 4 evaluation windows can be increased.
  • The system is well suited for retrofitting in existing systems because of its small space requirement.
  • The test is carried out during the ongoing production process.
  • Statistics information such as the number of missing parts or fault rate can be displayed on the monitor.
Anlage zur optischen Kontrolle von Innengewinde und Bauteilhöhe.

Wente/Thiedig GmbH

Gewerbepark Querumer Forst
Spechtweg 1
38108 Braunschweig

Tel:              +49 531 / 2 19 45 69 - 0
Fax:             +49 531 / 2 19 45 69 - 99
Mail:            info@wente-thiedig.de