Why Does The Fluoroplastic Centrifugal Pump Need To Be Filled before Starting?

Why do we need to divert water to fill the pump before starting the fluoroplastic centrifugal pump? Because the centrifugal pump relies on the centrifugal force of the impeller to form a vacuum suction to lift the water, so when the centrifugal pump starts, the gate valve must be closed first to fill the pump. The centrifugal pump can only be started when the water level exceeds the impeller and the air in the centrifugal pump is discharged. After starting, a vacuum is formed around the impeller, sucking water upward, and the gate valve can automatically open to lift the water. Therefore, the gate valve must be closed first. This is why it is important to divert water for irrigation before starting the centrifugal pump!

The Fluoroplastic Centrifugal Pump relies on the high-speed rotation of the impeller. The liquid flies out of the centrifugal pump under the action of centrifugal force. After the water in the pump is thrown out, a vacuum is formed in the impeller flow channel. The liquid is forced into the water inlet pipe under the action of air pressure, so that a low pressure is formed in the center of the impeller, and the liquid in the low tank can continue to be sucked up.

However, if the pump casing of a fluoroplastic centrifugal pump is filled with gas before starting, it will be difficult to form a vacuum when the gas in the center of the impeller is thrown after starting, and the liquid cannot be sucked up. Therefore, the fluorine-lined centrifugal pump cannot run empty.

Fluoroplastic Centrifugal Pump Before starting the centrifugal pump, liquid must be filled into the pump cavity. In order to prevent the liquid in the pump cavity from flowing into the low tank, it is recommended to install a bottom valve at the inlet. If the position of the centrifugal pump is lower than the liquid level in the tank, start the pump. No filling is required.

So, how should the centrifugal pump of fluoroplastic centrifugal pump be filled with liquid? Our Jiushi Pump Industry engineers have summarized the following methods:

1.Tap water filling method

For water pumps with low water quality requirements, or other material and liquid pumps where filling the pump with tap water has little impact on the conveying medium, tap water can be used for filling, which is very convenient.

2. Backflow filling method

Backflow filling uses the accumulated liquid in the high-level tank on the discharge side for backflow filling. When using this method, a manual pump must be used for the first start.

3. Downstream filling method

This method is used on many occasions in chemical pump installations. It only needs to make the position of the pump lower than the liquid level of the suction pool (trough), which is called perfusion. Because the liquid is always stored in the pump when installed in this way, there is no need to fill it up when the pump is turned on. When in use, install a valve in the suction pipeline to facilitate pump maintenance. This valve should use a gate valve, cock, etc. with small resistance. At the same time, do not forget to open it before starting the pump.

4. Pumping and sucking method

It uses air extraction equipment to remove the air from the centrifugal pump and suction pipe, and sucks the liquid up. The air extraction equipment can be a hand press and a motorized vacuum pump (often a water ring vacuum pump). The suction port of the vacuum pump should be connected to a higher part of the pump or the drain pipe as much as possible to remove all the gas in the pump.

Usage tips: Before priming the pump, you need to prime the pump. Close the inlet valve of the pump (if there is a check valve at the inlet, you can leave it open). Set up an irrigation branch pipe on the pump outlet pipe. You can directly pour water into the pump through the branch pipe. Wait until there is water in the branch pipe. When it overflows, stop filling, close the branch pipe valve, and start the pump. If you need to start the process of filling water, try to install a process water hose near the pump. There is no need to set up a vent pipe.