CYZ self-priming centrifugal pump

1. This pump is a self-priming centrifugal pump, which has the advantages of simple structure, convenient operation, stable operation, easy maintenance, high efficiency, long service life, and strong self-priming capability. It does not require a bottom valve in the pipeline; only a fixed amount of priming oil needs to be stored in the pump body before operation. When used on oil tankers or water transport ships, it can also serve as a tank cleaning pump with excellent tank cleaning effect.2. This pump is precision-made from high-quality materials, with an alloy mechanical seal that is durable. No safety valve is required in the discharge pipeline, and no bottom valve is needed in the suction pipeline, which simplifies the pipeline system and improves working conditions.

Working Principle:

All CYZ series self-priming pumps adopt an axial liquid-return pump body structure. The pump body consists of a suction chamber, a liquid storage chamber, a volute chamber, a liquid return hole, a gas-liquid separation chamber, etc. After the pump starts normally, the impeller draws in the liquid stored in the suction chamber and the air in the suction pipeline, and they are fully mixed inside the impeller. Under the action of centrifugal force, the liquid carrying the gas flows toward the outer edge of the volute chamber, forming a white foam belt with a certain thickness and a high-speed rotating liquid ring on the outer edge of the impeller. The gas-liquid mixture enters the gas-liquid separation chamber through the diffusion pipe. At this point, due to the sudden drop in flow velocity, the lighter gas is separated from the mixed gas-liquid, and the gas continues to rise and be discharged through the pump body's discharge port. The degassed liquid returns to the liquid storage chamber and enters the impeller again through the return hole, mixing with the gas sucked from the suction pipeline inside the impeller. Under the action of the high-speed rotating impeller, it flows toward the outer edge of the impeller again. As this process repeats continuously, the air in the suction pipeline decreases until the air is completely exhausted, completing the self-priming process, and the pump then operates normally.

Because this pump has this unique gas-exhausting capability, it can transport liquids containing gas without the need for a bottom valve, and it has excellent tank cleaning function when used on oil tankers.

Some pumps are also equipped with a cooling chamber at the bottom of their bearing bodies. When the bearing temperature rise exceeds 70°C due to bearing heating, coolant can be injected through any coolant pipe joint outside the cooling chamber for circulation cooling. The sealing mechanism that prevents liquid leakage from high-pressure to low-pressure areas inside the pump is composed of front and rear sealing rings. The front sealing ring is installed on the pump body, and the rear sealing ring is installed on the bearing body. After long-term operation of the pump, when the sealing rings wear to a certain extent and affect the pump's efficiency and self-priming performance, they should be replaced.

Pump Operation:

1. CYZ type self-priming oil pump relies on an internal balance mechanism to balance axial force. The balance device has balanced liquid outflow, and the balanced liquid is connected to the suction section via a balance pipe, or a short pipe is set outside the balance chamber, allowing the balanced liquid to flow out of the pump through the short pipe. To ensure normal pump operation, the balance pipe must not be blocked;

2. CYZ type self-priming pump rolling bearings have no cooling devices. Changes in bearing temperature rise reflect the pump's assembly quality. The bearing temperature rise shall not exceed 35°C above the ambient temperature, and the temperature shall not exceed 75°C;

3. The rotor of a CYZ type self-priming pump has a certain axial movement during operation, so the clearance between the end faces of the two couplings of the motor and the water pump must be ensured;

4. During the operation of a CYZ type self-priming pump, instruments, pump speed, and the wear conditions of the impeller, sealing ring, guide vane sleeve, balance disc, and shaft sleeve should be checked at regular intervals. If the wear is excessive, they should be replaced in time. In addition, monitor the pump's flow rate, head, temperature, and lubrication status. If a pump failure occurs, the pump should be stopped, and maintenance should be performed with reference to the fault troubleshooting table.