Pushing machine oil cylinder matching hydraulic system solenoid valve

The hydraulic system solenoid valve is matched with the oil cylinder of the pusher. In order to save energy, designers consider using low leakage or leak free hydraulic control valves in hydraulic system design, which puts higher requirements on the performance of hydraulic valves. Especially in the working conditions of load maintenance and pressure holding, the requirement for valve leakage will be higher, usually requiring a leakage rate of no more than 3 drops/minute. When such a requirement exists, design engineers usually choose lift type hydraulic valves, such as cone valve relief valves, cone valve solenoid valves, etc.
The methods for leak detection are currently not standardized for many factories, as shown in Figure 1. Although the "GB/T 8105-87 Test Methods for Pressure Control Valves" and "JB/T 10374-2013 Hydraulic Relief Valves" standards recommend measuring leakage using measuring cups or small flow meters, the measuring cup requires waiting for one minute for the residual oil in the pipeline to be drained before measuring within one minute, which is relatively inefficient; When measuring flow meters with small ranges, on the one hand, high-precision cylindrical gear flow meters with small ranges are very expensive. Due to the fact that most flow meters are volumetric, there is a certain volumetric efficiency, and the accuracy is generally within ± 0.5% F.S. For flow meters with a range of 0-5L, the error is around 0.05mL, so the accuracy is not even as intuitive and accurate as visual inspection; On the other hand, because the characteristics at rated flow rate need to be tested when testing the valve, and the range of the flowmeter is limited, it is necessary to switch between high and low flow rates, requiring a more complex control system. Pushing machine oil cylinder matching hydraulic system solenoid valve