Key Indicators for Hot Runner Sensor Lifespan Testing

For hot runner sensor lifespan assessment, there are four main critical signs. To be deemed qualified or acceptable, all four requirements must be satisfied, which directly relate to the stability and real service life:

1. Requirement for Cycle Count

This is the fundamental threshold that represents the real service life in manufacturing:

Typical civilian-grade sensors need at least 500 cycles, which equates to a real lifespan of one to two years.

High-end industrial-grade sensors, such the Kistler 6125A, have a lifespan of three to four years and require at least 1500 cycles.

2. Accuracy Measures Following Hot Running

The foundation of evaluating accuracy retention capability is this:

Zero drift ≤0.1%FS: To prevent pressure misjudgment during manufacturing, the output deviation under zero pressure should not surpass 0.1% of full scale;

Full scale accuracy deviation ≤ nominal accuracy: The deviation following cycling must be ≤0.25%FS for items such as the 6125A that have a nominal 0.25%FS;

Sensitivity drop ≤5%: In order to effectively depict the actual pressure, the decrease in sensitivity should not be greater than 5% of the initial sensitivity.

3. Reliability of Sealing

After testing, there must be no molten metal leakage into the hot runner mounting region and the sensor tail in order to prevent sensor damage from molten metal leaks. Due to the possibility of a short circuit and early sensor failure, any leakage will trigger an instantaneous failure.

4. Integrity of Structure

After cycling, there shouldn't be any bodily harm:

There should be no anomalous signal fluctuations, no leaps or disconnections in the output signal, and no cracks or deformations in the sensing diaphragm.