In-Mold Sensor Installation for Real-Time Polymer Gelation Inspection
In-mold dielectric and ultrasonic sensors eliminate conservative press hold timers by triggering part ejection precisely at polymer vitrification.
Ultrasonic Velocity
Meaning
Rate at which high frequency sound waves travel through a substance indicates its internal structure and composition. Measuring the ultrasonic velocity is a non destructive way to evaluate the quality of metal and composite structures. This value changes depending on the density and the elasticity of the material being tested.
Material Density
Consistent readings across a large part suggest that the material is uniform and free from hidden pockets of air. The ultrasonic velocity is higher in denser materials like steel than it is in less dense materials like aluminum. Engineers use this property to verify that a casting has the correct grain structure and has been properly heat treated.
Thickness Measurement
Calculating the distance to the far side of a part is possible by timing how long it takes for the sound wave to return. When the ultrasonic velocity is known for a specific material, the equipment can measure the thickness of a pipe or a tank without needing access to both sides. This technique is essential for checking for corrosion in existing industrial infrastructure.
Internal Flaw
Reflections of the sound wave from an unexpected surface inside the part indicate the presence of a crack or a void. The ultrasonic velocity will shift or the signal will weaken if the wave encounters a boundary that should not be there. The cost of calling a part ready for a high pressure environment without this test is the risk of a catastrophic failure in the field.