Different results of hydraulic slowly-closing structure improvement
Test device, as shown in figure 3 below. Using the gauge calibration, the differential pressure transmitter will stress signals, calibration record oscilloscope in good proportion R wave map reading every moment of the water hammer pressure changes. Figure 4 shows a common structure check (a) and ordinary structure check valves with hydraulic slowly-closing vice valve (b) of the comparison results.
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Test for 100 mm valve, pressure, flow rate 0.5 MPa 5 L/s. When the pump stopped suddenly, that power cut off after check valve inlet side pressure (4) curves.
Figure 4 (a) valve with hydraulic slowly-closing vice valve, the water hammer the shape-change 0.53 MPa, Figure 2 (b) for the main valve with the hydraulic slowly-closing vice valve, the water hammer the shape-change 0.04 MPa.
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