Plastics manufacturing
Automated Burst Pressure Test Rig
Challenge
A plastics manufacturer had to run burst pressure tests on components regularly and traceably. The test sequence was manual, pressure control imprecise, and the test reports had to be compiled by hand from measured values.
Solution
We automated the test rig step by step over five years: Siemens S7-1200 with PID Compact, high-pressure sensor and proportional pressure regulator, a Python script that generates finished PDF test reports from the PLC archives, and most recently a BLDC turntable for handling the specimens.
Result
Testing now runs reproducibly with automatic pressure control, and every test report is produced by script instead of by hand. For the 2026 relocation we redesigned the test station with a new cabinet, bill of materials and cost estimate.
Starting point
Burst pressure tests show at what pressure a plastic component fails. For quality assurance and customer evidence they must be repeatable and fully documented. The original rig required a lot of manual work: ramp up pressure, watch the values, note the results, write the report. That was slow and depended on who happened to be testing.
Control and pressure regulation
At the heart is a Siemens S7-1200 programmed in TIA Portal V16. Test pressure is controlled with PID Compact; an SMC proportional pressure regulator acts as the actuator and a Keller high-pressure sensor provides feedback. The rig runs defined pressure ramps and hold phases on its own and reliably detects the moment of burst. Measured values are stored in archives on the PLC.
Automatic test reports
A Python report script reads the PLC archives and generates a PDF test report for each test series with the pressure curve, characteristic values and specimen data. What used to be half an hour of Excel work is now one command. The reports are uniformly formatted and can be passed directly to customers or auditors.
Handling with a BLDC turntable
To test several specimens in sequence without re-clamping, we developed a turntable: BLDC motor with SimpleFOC, ESP32 control, AS5048A encoder for angle control and a web interface for operation. The specimen fixtures are designed in OpenSCAD and 3D-printed, so new component geometries can be accommodated in hours rather than weeks. Repeat moves are position-accurate.
Relocation 2026
Moving the test station called for a redesign: new control cabinet, complete bills of materials, a cost estimate and an assembly guide so the team can commission the rig at the new location themselves. Five years of continuous development show what matters to us: automation that grows with the operation instead of blocking it.