Issues with vehicle loading/unloading platforms and truck unloading pumps
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I have a question: During the unloading process, hoses were used for connection purposes. After the centrifugal pump started operating, pressure built up due to blockages in the downstream pipeline. About two minutes later, the operator noticed abnormal noises coming from the pump; they stopped the pump first and then closed the valve, which caused the inlet hose to burst. I wonder if this incident would have occurred if the valve had been closed first and then the pump stopped, given that there is a check valve at the pump’s outlet
I don’t quite understand why the inlet hose burst Does a faulty check valve cause pressurized fluid to flow back? This accident was not caused by stopping the pump or valve first, but rather by an obstruction in the subsequent process; it should be included in the unloading inspection procedures.
Hehe, there doesn’t seem to be any inevitable connection between such things and valve operation. Prolonged pressure retention is likely the main cause. I don’t know what material it is. Such incidents are more likely to occur with cryogenic liquids or other materials that easily vaporize at room temperature. Of course, in the case of ordinary liquids, it might still be a problem with the quality of the hose – factors such as aging or severe damage to the metal wires in the outer layer need to be checked.
It is known that it involves a \"steel wire reinforced plastic inner lining DN80 unloading hose, with benzene as the medium being transported; the pump’s head is 120 m, and the pressure buildup distance at the pump outlet is 1 km.\" Currently, there are two hypotheses: 1) Pressure builds up in the outlet pipeline; when the pump stops, the material in the outlet pipeline is released back into the pump inlet just before it passes through the check valve, resulting in an immediate increase in flow velocity at the pump inlet and a corresponding rise in pressure, which causes the connection of the inlet hose to burst
This connector is defective. The pressure release also returns to the large tank; why does this cause the joint to burst? Furthermore, for high-risk materials like benzene, such plastic pipes should not be used; a fixed connection is required. I’m very interested to know how you handle emergency responses in case of material leakage.
Does the pump not have overcurrent protection? With such a long pressure holding time, the pump should stop operating! Does the pump outlet check valve have a double line? Can the check valve core return to its original position? If the outlet fluid backflows to the inlet, it should go into the storage tank; however, if the liquid level in the tank is high and the static pressure is great, leakage may occur at points with weaker strength such as the inlet connections!
Centrifugal pumps do not do this; prolonged operation only leads to an increase in the temperature of the fluid inside the pump, causing it to vaporize