II. Structure principle

1. This cupping testing machine adopts a new structure principle for constant-rate loading of servo motor, and it can realize constant-rate control, and control of the stamping process by computer, and the stamping speed is stepless speed adjustable and it can be adjusted in advance. (In the past, oil source force loading of oil cylinder cannot realize constant-rate control.)

2. The clamping force is independently loaded by the hydraulic oil source, and the clamping force can be adjusted; the spoke-type sensor can directly measure force, and data can be displayed synchronously and calibrated independently.

3. The force measuring device adopts a spoke-type sensor instead of hydraulic sensor previously, and the cupping value measurement is completed by an encoder; during the test process, the plunger chip movement adopts the low-friction movement device created by our company, and combined with the high-accuracy spoke-type sensor (directly measuring force), it can realize accurate data collection, greatly improving the accuracy and reliability of cupping value measured by the testing machine. The perfect matching of the measuring device and loading device of this instrument and its control program well solves the previous problem of poor repeatability of test data, and it provides a reliable basis for our company to implement new regulations for metrological verification of cupping machines and cupping test methods.

4. It is convenient to replace cupping dies, and easy to load and unload specimens; after specimens are put in, they can be clamped when the automatic button is pressed, and the test parameters can be entered and changed, and the stamping process realizes closed-ring control; when the stamping force value declines, it will judge that a specimen has cracks, and it will automatically stop, and it is easy to observe specimen cracks at the same time. It displays test data on the computer, and has the function of peak value memory, i.e. maximum stamping force, cupping value and so on, and it can realize statement, storage, batch and curve drawing of test results, automatic memory of deformation height, and it can automatically restore to the state of waiting test after one test ends.
III. Technical parameters

Maximum test thickness	0.1～4mm (high-accuracy sensor)
Maximum width of plate	180mm
Maximum travel of plunger chip	100mm
Maximum stamping load	100kN
Clamping piston travel	21-31mm
Maximum clamping load	100kN
Resolution of cupping value	0.01mm
Load accuracy	±1%
Deformation accuracy	±1%
Test speed	0.05-100mm/min (stepless speed regulating)
Specification of cupping test die	Standard plunger ball SΦ20±0.05; standard fixed die bore diameter ф27±0.05mm
Computer display content	Clamping load, stamping force, displacement and cupping value, speed, test curve, etc.
Control mode	The computer automatically realizes the test process; the backend database adopts ACCES, and it can provide various formats of data transmission software according to the requirements of users.
Boundary dimension	930mm×1260mm×1400mm
Power supply	2kW/AC380V/50Hz
Weight	1000Kg
Adopt AC speed regulating system servo motor control	The electrical design satisfies the EMC safety standard, and it has such functions as limit protection and full range overload protection.