East Dp Boiler Feed Water Pumpself Balancing Multi-Stage Centrifugal Pump

Product Overview               

The DP series horizontal multi - stage centrifugal pumps are single - suction, multi - stage, self - balancing pumps. This series serves as a replacement for D - type horizontal multi - stage pumps. These products feature a wide operating range, excellent cavitation performance, stable operation, fewer wearing parts, high reliability, and low maintenance costs for users. Models with an "S" suffix have a first - stage double - suction structure, which offers even better cavitation performance.

Product Applications                

• DP - type: Used for transporting clean water without solid particles and with a temperature below 80°C, or liquids with physical and chemical properties similar to clean water.
• DP - M type: Used for transporting neutral mine water and other similar sewage with a solid particle content ≤ 1.5%, particle size ≤ 1.3mm, and a temperature below 80°C.
• DP - F type: Used for transporting corrosive liquids without solid particles and with a temperature below 80°C. The material of the pump can be reasonably selected according to the transported medium.
• DP - Y type: Used for transporting oil - based media without solid particles, with a temperature below 80°C and a viscosity less than 120 centistokes.
• DP - R type: Used for transporting clean water without solid particles and with a temperature not exceeding 105°C.

Product Features               

• Reliable and Safe Structure: The rotor components feature symmetrically - arranged impellers. The axial forces generated by the impellers cancel each other out, enabling self - balancing of the axial force inside the pump without the need for a balance disc structure. The residual axial force is borne by a pair of angular contact ball bearings.
• New Technology: The new throttle pressure - reducing device reduces leakage and improves efficiency on the one hand, and also provides auxiliary support to ensure the safe and stable operation of the pump.
• Reliable Sealing: The balance structure prevents excessive pressure in the mechanical seal chamber and packing chamber, extending the service life.
• Good Cavitation Resistance: With a first - stage impeller and a first - stage double - suction impeller featuring good cavitation performance, along with reliable materials, the pump can be applied in various scenarios with high requirements for net positive suction head.
• Reliable Mechanical Seal: There is no axial movement of the pump rotor, solving the problem of poor reliability of the mechanical seal in multi - stage pumps.
• Low Maintenance Rate: The failure - prone balance disc structure is eliminated, greatly improving reliability, reducing the number of maintenance times and lowering maintenance costs.
• High Efficiency: The impellers and diffusers are well - centered, avoiding the efficiency decline that occurs with the wear of the balance disc and the forward movement of the rotor.
• Adaptable to Various Media: By changing the material, it can transport media containing solid particles, oil, and corrosive substances.

For the self - balancing multi - stage centrifugal pump with a first - stage single - suction structure, the suction port on the suction section is in the horizontal direction (for DP - R, it is vertically upward), and the discharge port on the discharge section is vertically upward. The suction section, middle sections, discharge section, and secondary suction section of the pump are connected into one body by tightening bolts. The head can be adjusted by increasing or decreasing the number of pump stages.

The rotor is composed of components such as the first - stage impeller, impellers, throttle bushings, back - impellers, and shaft sleeves mounted on the shaft. The bearing adopts a "one - end fixed, one - end floating" grease - lubricated structure. A cylindrical roller bearing is used at the driving end, and a pair of angular contact ball bearings is used at the non - driving end to bear the residual axial force. The pair of angular contact ball bearings are installed face - to - face.

Sealing between the suction section, middle sections, and discharge section of the pump is achieved by sealant. Sealing rings, diffuser sealing rings, etc. are installed between the rotor and the fixed parts for sealing. When the sealing rings are worn to the extent that they affect the pump's performance, they should be replaced in a timely manner.

There are two types of shaft seals: packing seals and mechanical seals.

This series of pumps is directly driven by a prime mover through an elastic coupling. When viewed from the prime mover side, the pump rotates in a clockwise direction.

Structure Diagram
First - stage double - suction structure

The first-stage double-suction impeller of the self-balancing multi-stage centrifugal pump minimizes the net positive suction head required by the pump and improves its cavitation resistance. The suction port on the suction section is in the horizontal direction (for the DP-R model, it is vertically upward), and the discharge port on the discharge section is vertically upward. The suction section, middle sections, discharge section, and secondary suction section of the pump are connected into one body by tightening bolts. The head of the pump can be adjusted by increasing or decreasing the number of pump stages.

The rotor is composed of components such as the first-stage impeller, impellers, throttle bushings, back impellers, and shaft sleeves mounted on the shaft. The bearing adopts a "one fixed section and one floating section" grease-lubricated structure. A cylindrical roller bearing is used at the driving end, and a pair of angular contact ball bearings is used at the non-driving end to bear the residual axial force. The pair of angular contact ball bearings are installed face to face.

Sealing between the suction section, middle sections, and discharge section of the pump is achieved by sealant. Sealing rings, diffuser sealing rings, etc. are installed between the rotor and the fixed parts for sealing. When the sealing rings are worn to the extent that they affect the performance of the pump, they should be replaced in a timely manner.

There are two types of shaft seals: packing seals and mechanical seals.

This series of pumps is directly driven by a prime mover through an elastic coupling. When viewed from the direction of the prime mover, the pump rotates in a clockwise direction.

Main Components Material Table           

Type Spectrum Diagram