Injection molding

The importance of communication between the metrologist and the engineer

Computed tomography is the first choice for dimensional analyzing of injection molded parts. 

Plastic industry and MuScope

When the metrologist is sitting next to the engineer

Quality control is of crucial importance in the plastics industry, as even the smallest errors can have serious consequences. Components for medical devices, electrical connections and plastic housings are therefore subject to the strictest quality controls. Plastic products often have to be inspected for porosity, wall thickness and dimensional accuracy. In addition, foreign bodies such as dirt or metal particles can contaminate the finished product. Manufacturers make sure that their products meet the highest quality standards. First article inspection is one way to achieve this, as it ensures that each component meets the required specifications.

Simple analyze with X-Ray
Computed tomography has become an indispensable tool for quality assurance in the plastics industry. Sink marks, unwanted deformations and incorrect fibre alignments are detected and visualised with ease. With CT, not only individual parts can be inspected quickly and thoroughly, but also assemblies. For example, to detect unexpected problems, a fully assembled bottle cap can be tomographed. This allows fit and tightness to be checked in one. For more complex assemblies with moving elements, dynamic CT is ideal for analysing the actual function of the assembly. This state-of-the-art form of computer tomography enables video analysis in all four dimensions. The scan time is reduced to 0.1 seconds. If the required temporal resolution is higher, there is the alternative of a 2D X-Ray Slow-Motion Video. In this case, X-ray images are recorded at over 500 frames per second. With this technology, hidden and very fast-moving events are reliably imaged. Matching the individual components of an assembly thus becomes child’s play. Seeing more means making better decisions.
Dimensional comparison of a CT-Scan to the CAD
Contactless and non destructive 3D-Scanning
X-rays also show their advantages in soft materials or unstable shapes.
The non-contact measurement in the free state eliminates any physical influences on the measurement.
Computed tomography provides support for every type and size of moulding process used for plastics, rubber and polyurethane products. Rubber is commonly used for the manufacture of high performance products such as car tyres and industrial seals.
CT scanning of multi-material parts containing rubber, for example, can detect defects in the bonding of the material.
This information can then be used to optimise the manufacturing process until the final product meets the highest quality standards.

Rotation view, closure situation of a pet bottle, non-destructive, 3D

Simplify quality process
Regular requalification of the tools ensures lasting quality standards, but is associated with corresponding costs.
Depending on the component geometry, actual/actual comparisons can be made from the current 3D scan to the 3D data of the last inspection instead of time-consuming measurements.
If the deviations and consequently the wear of the tool are within the tolerance, further measurements are obsolete.
Horse-Shoe, made in rubber, measurement of inner structure
Tool correction and reverse engineering
Achieving perfect geometric accuracy of the parts is of utmost importance for a successful manufacturing process. A CAD model only ever shows the theoretically ideal shape. In most cases, not all deviations on the part can be eliminated by machine parameters such as temperatures or holding pressure times alone. We are happy to support you in calculating compensation geometries for your moulds based on the moulded parts. In doing so, we use modern techniques.
Traditionally, individual points on the warped surface are measured and then compensated using CAD software.
The communication between engineer and metrologist is then often done via tables with measured values and design instructions.

We circumvent this error-prone procedure by generating the compensation data directly from the 3D scan. As an interface for tool correction, full 3D data up to the fully compensated CAD file are then available.
Wear and tear analysis based on several CT-Scans

Best practice

Which tools are commonly used for mouldet parts

Computed tomography

  • 3D-Measurements
  • Porosity and inclusion analysis
  • Fiber analysis
  • Target actual comparison
  • Mechanical troubleshooting
  • Wall thickness analysis

Advantages

CT based data aquisition saves time by crossing standard processes. Troubleshooting of invisible situations get simple because of excellent visualisation possibilitys. Converted data can be used in third party tools.

Our services

All on this page described processes can be ordered as service at MuScope. Furthermore we provide consulting and coaching about the needed soft- and hardware. 

Insights

Have a look to some CT-Scans

MuScope services

Contact us for more informations

Our tomography specialist, will be happy to answer your questions and find solutions adapted to your situation.