Hydraulic Valve Test Bench

The test bench is designed for flow measurements on 3/2-port hydraulic valves with a pressure up to 30 bar. A mineral oil is used as test fluid. The semi-automatic test bench has two equal working stations. The operator inserts the part into the holding fixture and starts the test cycle with the start button. Now the work piece is fixed by a pneumatic cylinder and a cap closes the testing chamber. An electrical connection is established for driving the hydraulic valve.
Testing sequence:
-Flow measurement from port A to T with constant supply
 pressure and non triggered valve
-Flow measurement from port P to A with constant supply
 pressure and triggered valve
-Leakage flow measurement from port P to A with
 constant supply pressure and non triggered valve
-Leakage flow measurement from port A to T with
  constant supply pressure and triggered valve
-Step response of pressure at port A on a voltage pulse
At the end of the test sequence the testing chamber is opened. A part which stands the test is labeled by a pneumaticmechanical marker unit. Has a part failed the test, the protection door remains closed until the operator confirms the failure by pressing the respective button. 

Calibration and test line for pressure relief valves

This system is designed for the calibration of pressure relief valves with subsequent leak test.
All test and calibration parameters can be set by means of a process data editor on the PC.
Sequence in automatic mode:
• The nominal flow rate is pre-adjusted by a speed-controlled pump.
• Adjustment to nominal pressure (opening and closing of the valve) by a stepper motor.
• Adjustment of leakage pressure by I/P converter and measurement of the pressure and leak flow. 

Hydraulic Test Bench

The test bench is designed for adjusting and measuring 2/2–way pressure limiting valves.
At the beginning the measuring chamber where the valve is placed in, is evacuated as the test fluid flows through the valve. At the end of the evacuation cycle the valve and the measuring chamber are largely free from air.
Under constant volume flow the valve is adjusted to the nominal pressure up to 30 bar. The adjustment is carried out by means of a servo motor which presses a sleeve inside the valve until the nominal pressure is reached.
Characteristic curve
Recording of the valves characteristic curve P = f(I) with increasing and decreasing current at constant flow. At the end of the measurement the characteristic curve is analyzed.
Blow out of the measuring chamber
The measuring chamber is finally blown out with compressed air. The tested pressure limiting valve is cleaned by means of air nozzles which are placed directly above.
End of test
Parts which passed the test are marked with an impact power spindle. For failed parts the protection door keeps closed until the user has acknowledged the error. The station is installed twice in order to improve the output. Each station has its own separate components (pumps, regulators, measurement devices). 

Test bench for 5/2-directional valves

The test bench serves for the final testing of 5/2-directional valves which are used to control the exhaust valves on heavy diesel engines. For the testing the operator places the valve into the fixture and starts the test sequence.
After closing of the safety door the valve is automatically clamped and supplied with voltage.
The following measurements are carried out:
 Switching time measurement
 Leakage measurement
 Pressure progression during switching
 Flow resistance
The temperature of the testing oil is set in a 100 l tank at 40 ± 2°C.
The pressure is generated with a low pulse internal gear pump and controlled by a pneumatic pre-regulated pressure controller. The pump is additionally driven by a frequency converter.
The test bench is completely controlled by PC. The operator gets information about the bench status together with the current measured values and result values on the PC screen.

Sonplas GmbH- Sachsenring 57 - D-94315 Straubing - Deutschland - Tel: +49 (0) 94 21 / 92 75 - 0 Fax: +49 (0) 94 21 / 92 75 199 - info(at)

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