The cupping test machine is a testing device used to evaluate the formability, ductility, and fracture resistance of metal sheets, thin sheets, and coatings (such as paint and coatings). The core simulates the "tensile deformation process of metal in stamping processing" and measures the maximum bulge height (cupping value) generated by the material under specific pressure to determine whether the material meets the requirements of plastic processing such as stamping and stretching. It is widely used in fields such as automobile manufacturing, home appliance production, metal packaging, and hardware processing, and is a key equipment for quality control of metal materials and surface coatings.
The cup convex test applies pressure to the specimen clamped between the cushion die and the edge ring using a spherical punch until a penetrating crack appears on the specimen. The depth of punch penetration (cupping value, unit: millimeters) is used as the test result to reflect the plastic deformation ability of the material or the anti cracking performance of the coating. The experimental process can be divided into:
Clamping stage: The hydraulic system drives the clamping mold to fix the sample, ensuring that the edges do not slide.
Stamping stage: The punch is pressed into the sample at a constant speed to form indentations.
Crack detection: When the punching force drops (force value suddenly changes) or cracks are detected by optical sensors, the punching will automatically stop and the cup protrusion value will be recorded.
Automation and Intelligence:
The fully automatic model supports one click clamping, stamping, measurement, and data calculation, reducing human error.
The peak memory function automatically records parameters such as maximum impact force and cup protrusion value, generates reports, and supports curve drawing.
Some devices are equipped with cameras to accurately determine the cupping value at the moment of crack occurrence through video playback.
Key points of daily maintenance
Cleaning and lubrication:
After each inspection, clean the punch, lower mold seat, and edge pressing ring (wipe with a dust-free cloth dipped in alcohol to remove residual sample debris);
Add lubricating grease (such as lithium based grease) to the transmission mechanism (such as screw and guide rail) every month to avoid wear and affect accuracy;
Hydraulic models need to check the hydraulic oil level every quarter (replenish the same type of hydraulic oil when it is below the scale line), and replace the hydraulic oil filter element every year.
Calibration and verification:
The displacement sensor shall be calibrated once every 6 months (by entrusting a third-party metrology institution to issue a calibration certificate);
The edge pressure sensor is calibrated once a year to ensure the accuracy of pressure measurement;
The automatic crack detection system verifies the accuracy of crack detection every 3 months using standard crack samples (pre fabricated 0.5mm crack samples).