Life tests

Pulse liquid testing system including heat chambers

The device is used for development of controlled pulses of overpressure in the working liquid in the form of cyclic pulses with an accurately defined time period. The time of the pulse pressure is defined and the progress of the pulses may be trapezoidal, serrated or sinusoidal. Controlled movement causes definable pressure change according to the specification curve. This principle allows quick regulation changes relative to changing conditions in the circuit. In the period of this overpressure pulse the working liquid is heated to the defined temperature. The device is designed in a modular way, so each module can contain a different testing sample and a different type of test can be performed.

Medium temperature+150°C depending on the boiling point of the working substance used.
Ambient temperature+100°C
Medium flow rate20 l/min
Max. flow rateDepends on customer
Pressure0,1 - 10Bar - can be changed
Speed pulse0,1 - 20sec
Denso - Impulse pressure cycler ISO 1

Device for testing by hot air pulses (CAC, WCAC Pressure cycles)

The device is used for life testing of air exchangers (intercoolers) by pressure cycles at given temperature of the passing air and temperature in the surroundings of the tested exchangers.

The controlled parameters include the length of compressed air feed and release, the pressure pulse, which is controlled in its frequency and time of hold/drop and partly also in the shape of the entering and descending edges. The basic shape of the pulse is a serrated sinus curve with extending time intervals and a steep entering edge with the shape close to trapezoid.

Maximum feed air temperature235°c +/-5°C
Min. feed air temperature180°C +/-2°C
Maximum input pressure5.5bar +/-0.1
Average input pressure2bar +/-0.1
Min. pressure0 +0.2bar
Maximum pulse frequency1Hz +/-0.02
Average pulse frequency0.33Hz +/-0.02
Ambient temperature max.150°C +/-1°C
Average ambient temperature50°C +/-1°C
Max. number of pulse999 999

Device for testing by pressure pulses in liquid (CAC, WCAC Thermal cycles)

A universal test STAND with support circuits for testing of the life of liquid coolers by pressure impact tests.

The principle of pressure impact generation is based on very quick injection of the pressurised liquid stream into the tested sample, which is closed on the other side with a separation valve. After elapse of the time specified for the given pressure holding the release valve is opened and the whole process is repeated with negative pressure progress – the tested sample is emptied.

Unlike hydraulic pulsing (with a piston and a plunger) there is no possibility of online control of the entering/descending edges and their geometry.

Maximum scope of temperatures of the liquid+40 to +140 °C, depending on the substance used
Maximum permitted working pressure5 Bar
Minimum permitted working pressure0.1 Bar (at the pulse bottom turning point)
Accuracy of liquid temperature regulation+/-0.5 °C (after stabilisation)
Maximum scope of chamber temperatures+35 to +150 °C
Accuracy of chamber temperature regulation+/-0.5 °C (after stabilisation)
Maximum cycling frequency1,25 Hz
Minimum cycling frequency0.2 – 0.3 Hz, minimum flow is necessary for temperature regulation and non-destructive pump run
Zařízení Pro Testování Pulzními Tlaky V Kapalině

Device for exchanger testing by alternating temperature

The device is used for cyclic and proportional control of alternating stream of compressed air to samples (automotive air intercooler). After a predefined interval one sample is fed with hot air with regulated temperature and flow rate and another sample is fed with cold air with regulated temperature and flow rate. These flow rates repeat in cycles.

Maximum feed air temperature, hot side235°C+/-5°C
Mean feed air temperature, hot side180°C+/-5°C
Minimum feed air temperature30°C +/-5°C
Maximum input pressure3.5bar+/-0.05
Mean input pressure1,5bar/+0.08/-00.2
Cycle frequency4-40/ hr max.
Ambient temperature25 to 150°C +/-5°C
Max number of pulses9 999
Hot air flow ratemax. 500 +/-20kg/hr
Cold air flow ratemax. 300 +/-10kg/hr
Time of valve switching2-30sec