Exhaust air is also called bleed air. Before hydraulic test, it is a necessary step to bleed air from the hydraulic test equipment and the tested object, which is related to the accuracy of the hydrostatic pressure test.
Why Exhaust Air is Important for Hydraulic Test
In hydraulic test, a hydraulic test machine is required, which includes a pneumatic hydraulic pump, valves, reservoir and many pipelines. The hydraulic pump is the core component. And it can pressurize the test medium to generate hydraulic flow, and inject the high-pressure hydraulic flow into the tested object through valves and pipelines, so as to perform hydrostatic pressure testing or burst testing.
Before the hydraulic test, there is some air remaining the hydraulic test machine pipelines and the tested object. The trapped air will occupy the space in hydraulic circuit, thereby reducing the injection amount of hydraulic flow. What is worse, in the process of injecting high-pressure hydraulic flow, these residual air will form a large number of tiny air bubbles under the action of high pressure, which seriously affects the accuracy of the pressure index in the hydraulic test.
How to Exhaust Air Before Hydraulic Test
There are two ways to bleed air from the hydraulic test machine and the testing object before hydraulic pressure testing.
1. If your tested object is small-sized and the test pressure is not high, you could directly use the hydraulic pump built in the hydraulic test machine to inject hydraulic flow into the testing object circularly, thereby exhausting the residual air. Then you start the formal pressure testing.
2. If your testing object is large-sized and the test pressure is high, in order to quickly bleed air bubbles, we recommend adding an electric water injection pump in hydraulic test equipment. Specifically, before hydraulic testing, use the electric water injection pump to circularly pre-fill water or hydraulic oil into the testing object. During the repeated water injection process, the air bubbles will flow into the built-in reservoir of the test machine, and finally be discharged into the atmosphere through the vent of the reservoir lid. Then you could activate the hydraulic pump to inject high-pressure hydraulic flow for proceeding hydro test.
