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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.

Medium temperature and ambient temperature+125°C depending on the boiling point of the working substance used.

Medium flow rate……20 l/min i.e. 5 l/min per branch.
Medium flow rate……max. 290 l/min i.e. 72 l/min per branch.
Pressure 0.1 to 10 Bar …..applies to an installed double secondary cylinder (plunger) with 140 mm in diameter. The pressures may be changed by replacement of the secondary cylinders.


Device for testing by pressure pulses in liquid

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 pressure    5 Bar
Minimum permitted working pressure    0.1 Bar (at the pulse bottom turning point)
Accuracy of liquid temperature regulation    +/-0.5 deg.C (after stabilisation)
Maximum scope of chamber temperatures    +35 to +150 °C
Accuracy of chamber temperature regulation    +/-0.5 deg.C (after stabilisation)
Maximum cycling frequency    1.25 Hz
Minimum cycling frequency    0.2 – 0.3 Hz, minimum flow is necessary for temperature regulation and non-destructive pump run


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 temperature 235°C+/-5°C
Mean feed air temperature 180°C+/-2°C
Maximum input pressure 5.5 Bar+/-0.1
Mean input pressure 2 Bar+/-0.1
Min. pressure 0+0.2 Bar
Maximum pulse frequency 1Hz+/-0.02
Mean pulse frequency 0.33Hz+/-0.02
Ambient temperature max. 150°C+/-1°C
Mean ambient temperature 50°C+/-1°C
Max. number of pulses 9,999,999


Device for exchanger testing by alternating temperature (CAC, WCAC Thermal cycles)

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 side 235°C+/-5°C
Mean feed air temperature, hot side 180°C+/-5°C
Minimum feed air temperature 30°C +/-5°C
Maximum input pressure 3.5 Bar+/-0.05
Mean input pressure 1.5 Bar/+0.08/-00.2
Cycle frequency 4-40/ hr max.
ambient temperature 25 to 150°C +/-5°C
Max number of pulses 9,999
Hot air flow rate max. 500 +/-20kg/hr
Cold air flow rate max. 500 +/-10kg/hr
Time of valve switching 2-30sec


Device for inside corrosion (erosion) simulation

The device is designed and manufactured to allow for life tests of exchangers at given flow rate and temperature values. The maximum liquid flow rate value that can be set is 4 x 105 l / min at adjustable liquid temperature which can be set up to + 107°C.


Test device for testing by thermal cycles

The device is designed and made to allow for performance of thermal cycle tests (shock tests). The tested sample is washed by alternating streams of hot and cold liquid. The liquid flow rate may be set up to 34 l / min with liquid temperature cycling at -20 and + 109°C.


Pressure testing device

Test equipment for overpressure and under-pressure pulse testing and testing by static pressure

The device is designed and made to allow for performance of under-pressure and overpressure pulse tests. Adjustable under-pressure value –30 to –97kPa. Adjustable overpressure value 240 kPa.

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