Meaning
Technical metrology evaluates the physical proportions of a component to determine its compliance with engineering drawings. This dimensional inspection occurs at essential stages to detect shifts in the moulding process. It quantifies the effects of thermal shrinkage on the final shape.
Tolerance Verification
Measurement of specific features confirms whether the part falls within the upper and lower limits defined by the designer. During dimensional inspection, calipers or optical systems check essential diameters and wall thicknesses that affect the structural integrity of the assembly. Parts that exceed these limits are quarantined to prevent failures in downstream automation.
Process Correlation
Variations in the dimensions of a part reveal changes in the underlying moulding conditions such as melt temperature or hold time. If a dimensional inspection shows a trend toward the lower limit, it may indicate that the material is cooling too quickly or that the cavity pressure is insufficient. Maintaining a consistent measurement log allows the technician to adjust the press before the parts become non-conforming.
Permanent Assessment
Permanent changes in part geometry sometimes signal wear or damage to the steel surfaces of the mould. Regular dimensional inspection tracks the stability of fine details and shutoff heights over hundreds of thousands of cycles. Gradual drift in these measurements indicates the need for preventative maintenance or a full overhaul of the tool.
Precision declines.
