When the ISW horizontal pipe centrifugal pump is operated, the impeller rotates so that the center forms a vacuum zone to draw in liquid. If the low pressure in the vacuum zone is very low, the suction capacity of the ISW horizontal pipe centrifugal pump will be stronger, which is reflected in the increase in suction height. However, due to the low pressure in the vacuum zone, the liquid that is sucked up may cause a large amount of bubbles in the vacuum zone. The bubble-containing liquid swells or ruptures after being squeezed into the high pressure zone. Due to the disappearance of the bubble, a partial vacuum is generated, and the surrounding liquid flows to the center of the bubble at a very high speed, which instantaneously generates a great local impact force, causing an impact on the impeller and the pump casing, resulting in impeller damage. The process in which the impeller is damaged by the formation and rupture of bubbles in the pump is called cavitation.
When the ISW horizontal pipeline centrifugal pump is started, because the centrifugal pump has no self-priming ability, if there is air in the pump, because the air density is small, the centrifugal force generated after the impeller rotates is small, so the low pressure formed in the central region of the impeller is insufficient to suck in the liquid. So, even if the centrifugal pump is started, the delivery task cannot be completed. This phenomenon is called air binding. Therefore, in order to avoid the occurrence of air binding, the pump must be filled with the liquid to be delivered before starting the centrifugal pump. Of course, if the suction port of the centrifugal pump is placed under the liquid level of the liquid to be transported, the liquid will automatically flow into the pump, which is a special case. In either case, it is necessary to install a bottom valve in the suction line of the centrifugal pump. The function of the bottom valve is to prevent the liquid poured in before the start of the pump from flowing out of the pump. The filter can be installed in the suction pipe to block the liquid. The solids are sucked in to block the pipeline, and the pump casing discharge pipe is installed with a regulating valve to regulate the flow rate and open the pump to stop the pump.
From the reasons of the cavitation and gas binding of the ISW horizontal pipeline centrifugal pump: the gas binding generally occurs when the pump is started, which is caused by air in the pump body; and the cavitation is due to the vaporization of the liquid at a certain temperature. Pressure, thus causing cavitation, is closely related to the transportable medium and working conditions.
The main causes of cavitation are: excessively thin or excessive resistance of the inlet pipeline; medium with high temperature; excessive flow; pump suction is affected by excessive pump installation; selection problems, including pump type , the material of the pump, etc.
Solution: Clean the foreign matter in the inlet pipe so that the inlet is unblocked, and install the filter or increase the pipe diameter in the inlet pipe; reduce the temperature of the conveying medium; lower the installation height; re-select the pump, or improve some parts of the pump For example, use cavitation resistant materials.
In addition to the above solutions, a high-tech method is provided. If customers encounter such problems, they need to have professional personnel to guide the operation, otherwise it is only futile. Increase the pump inlet pressure method. For the ISW horizontal pipeline centrifugal pump, install a bypass pipe to introduce the pressure water in the water outlet pipe into the water inlet pipe, accelerate it with a nozzle, mix the high-speed water flow with the low-speed water flow in the water inlet pipe, and transfer energy. To increase the pressure on the pump inlet. Thereby eliminating the cavitation of the pump. The qi method is to add a small amount of air to the inlet side. The air will form tiny bubbles in the water. After entering the low-pressure cavitation zone, the bubbles are not easily collapsed, which acts as a damping force and absorbs the impact energy generated during cavitation. Can reduce or eliminate cavitation. When the water inlet side pressure is higher than the atmospheric pressure, the small air compressor is used to supplement the air; when the water inlet side pressure is lower than the atmospheric pressure, the natural gas is supplied.SHENZHEN CHONDEKUAI TECHNOLOGY CO.LTD , https://www.szsiheyi.com