Inspection systems for serial parts made of elastomer, plastics & silicone

Inspection systems for serial parts made of elastomer, plastics & silicone

The dimensional control and surface inspection of serial parts made of elastomer, plastics or silicone can easily and realiably be automated with optical inspection and sorting systems from NELA. We offer tailored solutions for products with different sizes, shapes and material characteristics.

Inspection parts (selection):

  • O-Rings
  • Molded articles
  • Oil seals
  • Stoppers

O-rings can be inspected in accordance with ISO 3601-3.

During the automated optical inspection, your products are checked for dimensional aspects as well as surface defects in the same cycle. Inspection requirements may include the following criteria, among others:

  • Inside and outside diameter
  • Cross-section diameter
  • Mismatch, off-register
  • Flash
  • Indentations
  • Flow lines, cracks 
  • Foreign material
  • Non-fills, holes


Depending on your product‘s characteristics and inspection requirements, we offer glass table or belt-driven inspection systems, also in combination with robot handling or other customized devices. 

In connection with our powerful NELA VisionCheck image processing software, inspection systems from NELA provide a highly efficient and reliable solution for a 100% control of your valued products.

Parting line - making the invisible visible

When it comes to the visual inspection of O-rings, the parting line on inside and outside diameter plays an important role. It is the area of the O-ring where many defects such as flash, indentation or roughened spots occur. Such defects are 
caused by production processes like mould separation, damaged moulds, or trimming and may cause faulty operation of an entire sub-assembly if they go undetected.

For a 100% inspection with minimal pseudo waste it is very important that the area around the parting line is perfectly illuminated to enable optical sensors to detect anomalies in the surface. O-rings, however, tend to have a very smooth 
surface which shines and reflects under direct light, making it difficult if not impossible to see defects in the relevant areas.

NELA has developed a new sensor specifically for O-ring applications which provides perfect illumination and, therefore, a highly improved detection of surface anomalies. The new multi-level illumination prevents reflections to the greatest possible extent. It creates a homogeneously illuminated surface which is ideal for the detection of defects. Anomalies such as indentations, projections or non-fills are easy to find, invisible defects become visible.

O-rings can be inspected in accordance with industrial standards, including but not limited to ISO 3601-3.


Parting line example: reflecting O-ring (left) and O-ring under new NELA sensor (right)