DIETZ automation GmbH

Videos

Video demonstrates the Manual Test with a test stand ValveExpert 8.x.x series. This type of tests is used for initial diagnostics of the valve under test in a manual mode. The current video demonstrates how to start the program, set pressure, apply the right control settings, control the valve under the test with different hydraulic configurations,….

Video demonstrates the Flow Test in V-Form with a test stand ValveExpert 8.x.x series. This test shows plot of the total flow through the valve under test. Precision of this type of the flow test is extremely high near the Bias point, and it allows to analyze the valve under test in the most important area. The Flow Test V-Form, Spool Position Test, and Control Port Pressure Test can be made at the same  time.

Video demonstrates the Flow Test in V-Form with a test stand ValveExpert 8.x.x series. This test shows plot of the total flow through the valve under test. Precision of this type of the flow test is extremely high near the Bias point, and it allows to analyze the valve under test in the most important area. The Flow Test V-Form, Spool Position Test, and Control Port Pressure Test can be made at the same  time.

Video demonstrates the Leakage Test with a test stand ValveExpert 8.x.x series. This test shows flow plot through the valve in case if the control ports are blocked. Analysis of this plot allows us to estimate problems with spool and bushing, as well as the problems with sealing and O-rings. Specially developed flow measurement system is based on an FPGA controller and allows precise measurement of both high and extremely low flow. The system is free from the zero-shift.

Differential Pressure Test with a test stand ValveExpert 8.x.x series. Video shows plot of the pressure difference in the control ports of the valve under test in case if the ports are blocked. Analysis of this plot gives very important information about the valve. To see the problems with spool and bushing the main parameters like Bias, Overlap,  Pressure Gain, Hysteresis,… will be automatically analyzed. The Differential Pressure Test, Pressure Tests in control ports, Leakage Test, and Spool Position Test can be made at the same  time.

Video demonstrates the Spool Position Test with a test stand ValveExpert 8.x.x series. Nowadays, most proportional valves are equipped with spool position transducers. The Spool Position Test shows plot of the spool position signal against the control signal. To support the Spool Position Test for aerospace valves, test equipment ValveExpert 8.x.x may include programmable electronics for LVDT/LVT transducers. The electronics is based on an extremely fast FPGA controller with a powerful software which allow to use the LVDT/LVT transducers for static and dynamic tests. 

Video shows Dynamic Test with a test stand ValveExpert 8.x.x series. This is the most important test to analyze “speed” of the valve under test. Basic plots of this test are Phase-Frequency Response and Amplitude-Frequency Characteristics. These data allow us to simulate a linear dynamical model or transfer function of the valve under test and use the data for simulations of machines.

Video demonstrates the Step Response Test with a test stand ValveExpert 8.x.x series. Step-type control signal is the most natural signal. Moreover, it can be used to analyze the mathematical model of your valve and dynamical behaviur of the machine. Step Response Test shows the response plot of the valve spool onto the step-type signal, and makes analysis of the parameters like Rise-Time, Saturation Time, and Overshoot.

Video shows the Flow Compensation System of a test stand ValveExpert 8.x.x series. In case of a high flow, pressure loss on flow meters, valves, and piping may significantly change the pressure drop through the valve under test, and the flow measurements will not be correct. The stands series ValveExpert allow dynamically adapt the supply pressure and compensate the pressure loss. In addition, the software ValveExpert includes a mathematical correction of the flow and a system to prognosticate the flow for different supply pressures. To demonstrate the Flow Prognostication, it is shown that the calculated flow for 210 bar does not depend on the actual supply pressure from 70 bar to 210 bar. A direct drive valve “DFPlus” valve from Parker Hannifin was used  for the current test.

Video demonstrates the Min/Max Adjustment Procedure with a test stand ValveExpert 8.x.x series. This type of tests is used to help adjust your valve. ValveExpert program informs the operator if the Max flow (flow for a defined “positive” control signal), the Min flow (flow for a defined “negative” control signal), and the differences between these values are in tolerance of the specification. Of course, the similar adjustments can be made for differential pressure, pressure in a control port, or spool position. Also, ValveExpert test equipment contains procedures to adjust values at fixed control signal and symmetry adjustment procedures which are required to adjust the Bias point for valves with overlaps.

Video shows the Flow Feedback System of a test stand ValveExpert 8.x.x series. The Flow Feedback System allows simply to find the control signal corresponding to the required flow. The system supports both Manual and Automatic modes, and can be used to find the flow Bias point or another flow point.

Video shows Pressure Feedback System of a test stand ValveExpert 8.x.x series. This system allows simply to find the control signal corresponding to the required Differential Pressure (or pressure in any of control ports). The Pressure Feedback System supports both Manual and Automatic modes, and can be used to find the pressure Bias point or other pressure point.

Video demonstrates a laboratory equipped with test stands ValveExpert 8.x series.

Scott Sund from GCC demonstrates how to test Bosch-Rexroth or similar valves with onboard electronics with our portable tester – ValveExpert Checker 2.x series.